Area of the OCCIPITAL LOBE concerned with the processing of visual information relayed via VISUAL PATHWAYS.
The electric response evoked in the cerebral cortex by visual stimulation or stimulation of the visual pathways.
The selecting and organizing of visual stimuli based on the individual's past experience.
Clarity or sharpness of OCULAR VISION or the ability of the eye to see fine details. Visual acuity depends on the functions of RETINA, neuronal transmission, and the interpretative ability of the brain. Normal visual acuity is expressed as 20/20 indicating that one can see at 20 feet what should normally be seen at that distance. Visual acuity can also be influenced by brightness, color, and contrast.
The total area or space visible in a person's peripheral vision with the eye looking straightforward.
Set of cell bodies and nerve fibers conducting impulses from the eyes to the cerebral cortex. It includes the RETINA; OPTIC NERVE; optic tract; and geniculocalcarine tract.
Mental process to visually perceive a critical number of facts (the pattern), such as characters, shapes, displays, or designs.
Investigative technique commonly used during ELECTROENCEPHALOGRAPHY in which a series of bright light flashes or visual patterns are used to elicit brain activity.
Method of measuring and mapping the scope of vision, from central to peripheral of each eye.
The process in which light signals are transformed by the PHOTORECEPTOR CELLS into electrical signals which can then be transmitted to the brain.
Visual impairments limiting one or more of the basic functions of the eye: visual acuity, dark adaptation, color vision, or peripheral vision. These may result from EYE DISEASES; OPTIC NERVE DISEASES; VISUAL PATHWAY diseases; OCCIPITAL LOBE diseases; OCULAR MOTILITY DISORDERS; and other conditions (From Newell, Ophthalmology: Principles and Concepts, 7th ed, p132).
Focusing on certain aspects of current experience to the exclusion of others. It is the act of heeding or taking notice or concentrating.
The real or apparent movement of objects through the visual field.
The time from the onset of a stimulus until a response is observed.
The ability to detect sharp boundaries (stimuli) and to detect slight changes in luminance at regions without distinct contours. Psychophysical measurements of this visual function are used to evaluate visual acuity and to detect eye disease.
The awareness of the spatial properties of objects; includes physical space.
A series of tests used to assess various functions of the eyes.
The positioning and accommodation of eyes that allows the image to be brought into place on the FOVEA CENTRALIS of each eye.
The inability to see or the loss or absence of perception of visual stimuli. This condition may be the result of EYE DISEASES; OPTIC NERVE DISEASES; OPTIC CHIASM diseases; or BRAIN DISEASES affecting the VISUAL PATHWAYS or OCCIPITAL LOBE.
Voluntary or reflex-controlled movements of the eye.
Imaging techniques used to colocalize sites of brain functions or physiological activity with brain structures.
The science dealing with the correlation of the physical characteristics of a stimulus, e.g., frequency or intensity, with the response to the stimulus, in order to assess the psychologic factors involved in the relationship.
The coordination of a sensory or ideational (cognitive) process and a motor activity.
The blending of separate images seen by each eye into one composite image.
Signals for an action; that specific portion of a perceptual field or pattern of stimuli to which a subject has learned to respond.
The ten-layered nervous tissue membrane of the eye. It is continuous with the OPTIC NERVE and receives images of external objects and transmits visual impulses to the brain. Its outer surface is in contact with the CHOROID and the inner surface with the VITREOUS BODY. The outer-most layer is pigmented, whereas the inner nine layers are transparent.
Differential response to different stimuli.
The absence or restriction of the usual external sensory stimuli to which the individual responds.
The sensory discrimination of a pattern shape or outline.
Non-invasive method of demonstrating internal anatomy based on the principle that atomic nuclei in a strong magnetic field absorb pulses of radiofrequency energy and emit them as radiowaves which can be reconstructed into computerized images. The concept includes proton spin tomographic techniques.
Vision considered to be inferior to normal vision as represented by accepted standards of acuity, field of vision, or motility. Low vision generally refers to visual disorders that are caused by diseases that cannot be corrected by refraction (e.g., MACULAR DEGENERATION; RETINITIS PIGMENTOSA; DIABETIC RETINOPATHY, etc.).
The minimum amount of stimulus energy necessary to elicit a sensory response.
Images seen by one eye.
An abrupt voluntary shift in ocular fixation from one point to another, as occurs in reading.
Partial or complete loss of vision in one half of the visual field(s) of one or both eyes. Subtypes include altitudinal hemianopsia, characterized by a visual defect above or below the horizontal meridian of the visual field. Homonymous hemianopsia refers to a visual defect that affects both eyes equally, and occurs either to the left or right of the midline of the visual field. Binasal hemianopsia consists of loss of vision in the nasal hemifields of both eyes. Bitemporal hemianopsia is the bilateral loss of vision in the temporal fields. Quadrantanopsia refers to loss of vision in one quarter of the visual field in one or both eyes.
Behavioral manifestations of cerebral dominance in which there is preferential use and superior functioning of either the left or the right side, as in the preferred use of the right hand or right foot.
Part of the DIENCEPHALON inferior to the caudal end of the dorsal THALAMUS. Includes the lateral geniculate body which relays visual impulses from the OPTIC TRACT to the calcarine cortex, and the medial geniculate body which relays auditory impulses from the lateral lemniscus to the AUDITORY CORTEX.
Persons with loss of vision such that there is an impact on activities of daily living.
Theoretical representations that simulate the behavior or activity of the neurological system, processes or phenomena; includes the use of mathematical equations, computers, and other electronic equipment.
A species of the genus MACACA inhabiting India, China, and other parts of Asia. The species is used extensively in biomedical research and adapts very well to living with humans.
The anterior pair of the quadrigeminal bodies which coordinate the general behavioral orienting responses to visual stimuli, such as whole-body turning, and reaching.
A nonspecific term referring to impaired vision. Major subcategories include stimulus deprivation-induced amblyopia and toxic amblyopia. Stimulus deprivation-induced amblyopia is a developmental disorder of the visual cortex. A discrepancy between visual information received by the visual cortex from each eye results in abnormal cortical development. STRABISMUS and REFRACTIVE ERRORS may cause this condition. Toxic amblyopia is a disorder of the OPTIC NERVE which is associated with ALCOHOLISM, tobacco SMOKING, and other toxins and as an adverse effect of the use of some medications.
A localized defect in the visual field bordered by an area of normal vision. This occurs with a variety of EYE DISEASES (e.g., RETINAL DISEASES and GLAUCOMA); OPTIC NERVE DISEASES, and other conditions.
Processes and properties of the EYE as a whole or of any of its parts.
The basic cellular units of nervous tissue. Each neuron consists of a body, an axon, and dendrites. Their purpose is to receive, conduct, and transmit impulses in the NERVOUS SYSTEM.
The domestic cat, Felis catus, of the carnivore family FELIDAE, comprising over 30 different breeds. The domestic cat is descended primarily from the wild cat of Africa and extreme southwestern Asia. Though probably present in towns in Palestine as long ago as 7000 years, actual domestication occurred in Egypt about 4000 years ago. (From Walker's Mammals of the World, 6th ed, p801)
Cognitive disorders characterized by an impaired ability to perceive the nature of objects or concepts through use of the sense organs. These include spatial neglect syndromes, where an individual does not attend to visual, auditory, or sensory stimuli presented from one side of the body.
Upper central part of the cerebral hemisphere. It is located posterior to central sulcus, anterior to the OCCIPITAL LOBE, and superior to the TEMPORAL LOBES.
The functional superiority and preferential use of one eye over the other. The term is usually applied to superiority in sighting (VISUAL PERCEPTION) or motor task but not difference in VISUAL ACUITY or dysfunction of one of the eyes. Ocular dominance can be modified by visual input and NEUROTROPHIC FACTORS.
Perception of three-dimensionality.
A pair of ophthalmic lenses in a frame or mounting which is supported by the nose and ears. The purpose is to aid or improve vision. It does not include goggles or nonprescription sun glasses for which EYE PROTECTIVE DEVICES is available.
The misinterpretation of a real external, sensory experience.
Photosensitive protein complexes of varied light absorption properties which are expressed in the PHOTORECEPTOR CELLS. They are OPSINS conjugated with VITAMIN A-based chromophores. Chromophores capture photons of light, leading to the activation of opsins and a biochemical cascade that ultimately excites the photoreceptor cells.
Elements of limited time intervals, contributing to particular results or situations.
Recording of electric potentials in the retina after stimulation by light.
An illusion of vision usually affecting spatial relations.
A genus of the subfamily CERCOPITHECINAE, family CERCOPITHECIDAE, consisting of 16 species inhabiting forests of Africa, Asia, and the islands of Borneo, Philippines, and Celebes.
Deviations from the average or standard indices of refraction of the eye through its dioptric or refractive apparatus.
An area approximately 1.5 millimeters in diameter within the macula lutea where the retina thins out greatly because of the oblique shifting of all layers except the pigment epithelium layer. It includes the sloping walls of the fovea (clivus) and contains a few rods in its periphery. In its center (foveola) are the cones most adapted to yield high visual acuity, each cone being connected to only one ganglion cell. (Cline et al., Dictionary of Visual Science, 4th ed)
A statistical technique that isolates and assesses the contributions of categorical independent variables to variation in the mean of a continuous dependent variable.
Lower lateral part of the cerebral hemisphere responsible for auditory, olfactory, and semantic processing. It is located inferior to the lateral fissure and anterior to the OCCIPITAL LOBE.
A mechanism of communicating one's own sensory system information about a task, movement or skill.
The adjustment of the eye to variations in the intensity of light. Light adaptation is the adjustment of the eye when the light threshold is increased; DARK ADAPTATION when the light is greatly reduced. (From Cline et al., Dictionary of Visual Science, 4th ed)
Artificial device such as an externally-worn camera attached to a stimulator on the RETINA, OPTIC NERVE, or VISUAL CORTEX, intended to restore or amplify vision.
A technique of inputting two-dimensional images into a computer and then enhancing or analyzing the imagery into a form that is more useful to the human observer.
The process whereby auditory stimuli are selected, organized, and interpreted by the organism.
Relatively permanent change in behavior that is the result of past experience or practice. The concept includes the acquisition of knowledge.
An ocular disease, occurring in many forms, having as its primary characteristics an unstable or a sustained increase in the intraocular pressure which the eye cannot withstand without damage to its structure or impairment of its function. The consequences of the increased pressure may be manifested in a variety of symptoms, depending upon type and severity, such as excavation of the optic disk, hardness of the eyeball, corneal anesthesia, reduced visual acuity, seeing of colored halos around lights, disturbed dark adaptation, visual field defects, and headaches. (Dictionary of Visual Science, 4th ed)
Use of sound to elicit a response in the nervous system.
The interference of one perceptual stimulus with another causing a decrease or lessening in perceptual effectiveness.
The visually perceived property of objects created by absorption or reflection of specific wavelengths of light.
Recording of electric currents developed in the brain by means of electrodes applied to the scalp, to the surface of the brain, or placed within the substance of the brain.
Misalignment of the visual axes of the eyes. In comitant strabismus the degree of ocular misalignment does not vary with the direction of gaze. In noncomitant strabismus the degree of misalignment varies depending on direction of gaze or which eye is fixating on the target. (Miller, Walsh & Hoyt's Clinical Neuro-Ophthalmology, 4th ed, p641)
Partial or complete opacity on or in the lens or capsule of one or both eyes, impairing vision or causing blindness. The many kinds of cataract are classified by their morphology (size, shape, location) or etiology (cause and time of occurrence). (Dorland, 27th ed)
The removal of a cataractous CRYSTALLINE LENS from the eye.
The illumination of an environment and the arrangement of lights to achieve an effect or optimal visibility. Its application is in domestic or in public settings and in medical and non-medical environments.
That portion of the electromagnetic spectrum in the visible, ultraviolet, and infrared range.
Function of the human eye that is used in bright illumination or in daylight (at photopic intensities). Photopic vision is performed by the three types of RETINAL CONE PHOTORECEPTORS with varied peak absorption wavelengths in the color spectrum (from violet to red, 400 - 700 nm).
A subjective visual sensation with the eyes closed and in the absence of light. Phosphenes can be spontaneous, or induced by chemical, electrical, or mechanical (pressure) stimuli which cause the visual field to light up without optical inputs.
The anterior portion of the head that includes the skin, muscles, and structures of the forehead, eyes, nose, mouth, cheeks, and jaw.
Remembrance of information for a few seconds to hours.
Adjustment of the eyes under conditions of low light. The sensitivity of the eye to light is increased during dark adaptation.
Neurons of the innermost layer of the retina, the internal plexiform layer. They are of variable sizes and shapes, and their axons project via the OPTIC NERVE to the brain. A small subset of these cells act as photoreceptors with projections to the SUPRACHIASMATIC NUCLEUS, the center for regulating CIRCADIAN RHYTHM.
Application of tests and examinations to identify visual defects or vision disorders occurring in specific populations, as in school children, the elderly, etc. It is differentiated from VISION TESTS, which are given to evaluate/measure individual visual performance not related to a specific population.
Photosensitive afferent neurons located primarily within the FOVEA CENTRALIS of the MACULA LUTEA. There are three major types of cone cells (red, blue, and green) whose photopigments have different spectral sensitivity curves. Retinal cone cells operate in daylight vision (at photopic intensities) providing color recognition and central visual acuity.
The X-shaped structure formed by the meeting of the two optic nerves. At the optic chiasm the fibers from the medial part of each retina cross to project to the other side of the brain while the lateral retinal fibers continue on the same side. As a result each half of the brain receives information about the contralateral visual field from both eyes.
The ability to respond to segments of the perceptual experience rather than to the whole.
The sensory interpretation of the dimensions of objects.
The knowledge or perception that someone or something present has been previously encountered.
Learning that is manifested in the ability to respond differentially to various stimuli.
Diseases affecting the eye.
The part of CENTRAL NERVOUS SYSTEM that is contained within the skull (CRANIUM). Arising from the NEURAL TUBE, the embryonic brain is comprised of three major parts including PROSENCEPHALON (the forebrain); MESENCEPHALON (the midbrain); and RHOMBENCEPHALON (the hindbrain). The developed brain consists of CEREBRUM; CEREBELLUM; and other structures in the BRAIN STEM.
Conditions which produce injury or dysfunction of the second cranial or optic nerve, which is generally considered a component of the central nervous system. Damage to optic nerve fibers may occur at or near their origin in the retina, at the optic disk, or in the nerve, optic chiasm, optic tract, or lateral geniculate nuclei. Clinical manifestations may include decreased visual acuity and contrast sensitivity, impaired color vision, and an afferent pupillary defect.
Psychophysical technique that permits the estimation of the bias of the observer as well as detectability of the signal (i.e., stimulus) in any sensory modality. (From APA, Thesaurus of Psychological Index Terms, 8th ed.)
The absence of light.
The capacity of the NERVOUS SYSTEM to change its reactivity as the result of successive activations.
Visualization of a vascular system after intravenous injection of a fluorescein solution. The images may be photographed or televised. It is used especially in studying the retinal and uveal vasculature.
Complex mental function having four distinct phases: (1) memorizing or learning, (2) retention, (3) recall, and (4) recognition. Clinically, it is usually subdivided into immediate, recent, and remote memory.
The organ of sight constituting a pair of globular organs made up of a three-layered roughly spherical structure specialized for receiving and responding to light.
The point or frequency at which all flicker of an intermittent light stimulus disappears.
Tests designed to assess neurological function associated with certain behaviors. They are used in diagnosing brain dysfunction or damage and central nervous system disorders or injury.
The 2nd cranial nerve which conveys visual information from the RETINA to the brain. The nerve carries the axons of the RETINAL GANGLION CELLS which sort at the OPTIC CHIASM and continue via the OPTIC TRACTS to the brain. The largest projection is to the lateral geniculate nuclei; other targets include the SUPERIOR COLLICULI and the SUPRACHIASMATIC NUCLEI. Though known as the second cranial nerve, it is considered part of the CENTRAL NERVOUS SYSTEM.
The non-genetic biological changes of an organism in response to challenges in its ENVIRONMENT.
The difference between two images on the retina when looking at a visual stimulus. This occurs since the two retinas do not have the same view of the stimulus because of the location of our eyes. Thus the left eye does not get exactly the same view as the right eye.
Abrupt changes in the membrane potential that sweep along the CELL MEMBRANE of excitable cells in response to excitation stimuli.
The act, process, or result of passing from one place or position to another. It differs from LOCOMOTION in that locomotion is restricted to the passing of the whole body from one place to another, while movement encompasses both locomotion but also a change of the position of the whole body or any of its parts. Movement may be used with reference to humans, vertebrate and invertebrate animals, and microorganisms. Differentiate also from MOTOR ACTIVITY, movement associated with behavior.
The act of knowing or the recognition of a distance by recollective thought, or by means of a sensory process which is under the influence of set and of prior experience.
Relatively bright light, or the dazzling sensation of relatively bright light, which produces unpleasantness or discomfort, or which interferes with optimal VISION, OCULAR. (Cline et al., Dictionary of Visual Science, 4th ed)
The detailed examination of observable activity or behavior associated with the execution or completion of a required function or unit of work.
An imaging method using LASERS that is used for mapping subsurface structure. When a reflective site in the sample is at the same optical path length (coherence) as the reference mirror, the detector observes interference fringes.
Scales, questionnaires, tests, and other methods used to assess pain severity and duration in patients or experimental animals to aid in diagnosis, therapy, and physiological studies.
Total loss of vision in all or part of the visual field due to bilateral OCCIPITAL LOBE (i.e., VISUAL CORTEX) damage or dysfunction. Anton syndrome is characterized by the psychic denial of true, organic cortical blindness. (Adams et al., Principles of Neurology, 6th ed, p460)
Electrical responses recorded from nerve, muscle, SENSORY RECEPTOR, or area of the CENTRAL NERVOUS SYSTEM following stimulation. They range from less than a microvolt to several microvolts. The evoked potential can be auditory (EVOKED POTENTIALS, AUDITORY), somatosensory (EVOKED POTENTIALS, SOMATOSENSORY), visual (EVOKED POTENTIALS, VISUAL), or motor (EVOKED POTENTIALS, MOTOR), or other modalities that have been reported.
Subjectively experienced sensations in the absence of an appropriate stimulus, but which are regarded by the individual as real. They may be of organic origin or associated with MENTAL DISORDERS.
A meshlike structure composed of interconnecting nerve cells that are separated at the synaptic junction or joined to one another by cytoplasmic processes. In invertebrates, for example, the nerve net allows nerve impulses to spread over a wide area of the net because synapses can pass information in any direction.
Degenerative changes in the RETINA usually of older adults which results in a loss of vision in the center of the visual field (the MACULA LUTEA) because of damage to the retina. It occurs in dry and wet forms.
Removal of the whole or part of the vitreous body in treating endophthalmitis, diabetic retinopathy, retinal detachment, intraocular foreign bodies, and some types of glaucoma.
Refraction of LIGHT effected by the media of the EYE.
The concave interior of the eye, consisting of the retina, the choroid, the sclera, the optic disk, and blood vessels, seen by means of the ophthalmoscope. (Cline et al., Dictionary of Visual Science, 4th ed)
Normal nystagmus produced by looking at objects moving across the field of vision.
Dominance of one cerebral hemisphere over the other in cerebral functions.
Sensation of making physical contact with objects, animate or inanimate. Tactile stimuli are detected by MECHANORECEPTORS in the skin and mucous membranes.
Glaucoma in which the angle of the anterior chamber is open and the trabecular meshwork does not encroach on the base of the iris.
Loss of the ability to comprehend the meaning or recognize the importance of various forms of stimulation that cannot be attributed to impairment of a primary sensory modality. Tactile agnosia is characterized by an inability to perceive the shape and nature of an object by touch alone, despite unimpaired sensation to light touch, position, and other primary sensory modalities.
Motion of an object in which either one or more points on a line are fixed. It is also the motion of a particle about a fixed point. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)
The aperture in the iris through which light passes.
Term generally used to describe complaints related to refractive error, ocular muscle imbalance, including pain or aching around the eyes, burning and itchiness of the eyelids, ocular fatigue, and headaches.
A species of the genus MACACA which typically lives near the coast in tidal creeks and mangrove swamps primarily on the islands of the Malay peninsula.
An oval area in the retina, 3 to 5 mm in diameter, usually located temporal to the posterior pole of the eye and slightly below the level of the optic disk. It is characterized by the presence of a yellow pigment diffusely permeating the inner layers, contains the fovea centralis in its center, and provides the best phototropic visual acuity. It is devoid of retinal blood vessels, except in its periphery, and receives nourishment from the choriocapillaris of the choroid. (From Cline et al., Dictionary of Visual Science, 4th ed)
Specialized cells in the invertebrates that detect and transduce light. They are predominantly rhabdomeric with an array of photosensitive microvilli. Illumination depolarizes invertebrate photoreceptors by stimulating Na+ influx across the plasma membrane.
In invertebrate zoology, a lateral lobe of the FOREBRAIN in certain ARTHROPODS. In vertebrate zoology, either of the corpora bigemina of non-mammalian VERTEBRATES. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed, p1329)
The thin layer of GRAY MATTER on the surface of the CEREBRAL HEMISPHERES that develops from the TELENCEPHALON and folds into gyri and sulchi. It reaches its highest development in humans and is responsible for intellectual faculties and higher mental functions.
Sensory functions that transduce stimuli received by proprioceptive receptors in joints, tendons, muscles, and the INNER EAR into neural impulses to be transmitted to the CENTRAL NERVOUS SYSTEM. Proprioception provides sense of stationary positions and movements of one's body parts, and is important in maintaining KINESTHESIA and POSTURAL BALANCE.
A purplish-red, light-sensitive pigment found in RETINAL ROD CELLS of most vertebrates. It is a complex consisting of a molecule of ROD OPSIN and a molecule of 11-cis retinal (RETINALDEHYDE). Rhodopsin exhibits peak absorption wavelength at about 500 nm.
The statistical reproducibility of measurements (often in a clinical context), including the testing of instrumentation or techniques to obtain reproducible results. The concept includes reproducibility of physiological measurements, which may be used to develop rules to assess probability or prognosis, or response to a stimulus; reproducibility of occurrence of a condition; and reproducibility of experimental results.
Defects of color vision are mainly hereditary traits but can be secondary to acquired or developmental abnormalities in the CONES (RETINA). Severity of hereditary defects of color vision depends on the degree of mutation of the ROD OPSINS genes (on X CHROMOSOME and CHROMOSOME 3) that code the photopigments for red, green and blue.
Methods and procedures for recording EYE MOVEMENTS.
Photosensitive proteins expressed in the ROD PHOTORECEPTOR CELLS. They are the protein components of rod photoreceptor pigments such as RHODOPSIN.
Voluntary or involuntary motion of head that may be relative to or independent of body; includes animals and humans.
Lack of correspondence between the way a stimulus is commonly perceived and the way an individual perceives it under given conditions.
Neural tracts connecting one part of the nervous system with another.
Damage or trauma inflicted to the eye by external means. The concept includes both surface injuries and intraocular injuries.
A refractive error in which rays of light entering the EYE parallel to the optic axis are brought to a focus in front of the RETINA when accommodation (ACCOMMODATION, OCULAR) is relaxed. This results from an overly curved CORNEA or from the eyeball being too long from front to back. It is also called nearsightedness.
Recording of the average amplitude of the resting potential arising between the cornea and the retina in light and dark adaptation as the eyes turn a standard distance to the right and the left. The increase in potential with light adaptation is used to evaluate the condition of the retinal pigment epithelium.
The observable response an animal makes to any situation.
Large mass of nuclei forming the most caudal portion of the THALAMUS and overhanging the GENICULATE BODIES and the dorsolateral surface of the MIDBRAIN. It is divided into four parts: the lateral, medial, inferior, and oral pulvinar nuclei.
Analytical technique for studying substances present at enzyme concentrations in single cells, in situ, by measuring light absorption. Light from a tungsten strip lamp or xenon arc dispersed by a grating monochromator illuminates the optical system of a microscope. The absorbance of light is measured (in nanometers) by comparing the difference between the image of the sample and a reference image.
The act of "taking account" of an object or state of affairs. It does not imply assessment of, nor attention to the qualities or nature of the object.
Sense of movement of a part of the body, such as movement of fingers, elbows, knees, limbs, or weights.
A specific stage in animal and human development during which certain types of behavior normally are shaped and molded for life.
A perceptual phenomenon used by Gestalt psychologists to demonstrate that events in one part of the perceptual field may affect perception in another part.
Devices that help people with impaired sensory responses.
Evaluation undertaken to assess the results or consequences of management and procedures used in combating disease in order to determine the efficacy, effectiveness, safety, and practicability of these interventions in individual cases or series.
Theoretical representations that simulate psychological processes and/or social processes. These include the use of mathematical equations, computers, and other electronic equipment.
A mechanism of communication within a system in that the input signal generates an output response which returns to influence the continued activity or productivity of that system.
Input/output devices designed to receive data in an environment associated with the job to be performed, and capable of transmitting entries to, and obtaining output from, the system of which it is a part. (Computer Dictionary, 4th ed.)
An oval, bony chamber of the inner ear, part of the bony labyrinth. It is continuous with bony COCHLEA anteriorly, and SEMICIRCULAR CANALS posteriorly. The vestibule contains two communicating sacs (utricle and saccule) of the balancing apparatus. The oval window on its lateral wall is occupied by the base of the STAPES of the MIDDLE EAR.
Intellectual or mental process whereby an organism obtains knowledge.
Physical motion, i.e., a change in position of a body or subject as a result of an external force. It is distinguished from MOVEMENT, a process resulting from biological activity.
Eye movements that are slow, continuous, and conjugate and occur when a fixed object is moved slowly.
The study of the generation and behavior of electrical charges in living organisms particularly the nervous system and the effects of electricity on living organisms.
The ability to estimate periods of time lapsed or duration of time.
The process of discovering or asserting an objective or intrinsic relation between two objects or concepts; a faculty or power that enables a person to make judgments; the process of bringing to light and asserting the implicit meaning of a concept; a critical evaluation of a person or situation.
Specialized cells that detect and transduce light. They are classified into two types based on their light reception structure, the ciliary photoreceptors and the rhabdomeric photoreceptors with MICROVILLI. Ciliary photoreceptor cells use OPSINS that activate a PHOSPHODIESTERASE phosphodiesterase cascade. Rhabdomeric photoreceptor cells use opsins that activate a PHOSPHOLIPASE C cascade.
Fluid accumulation in the outer layer of the MACULA LUTEA that results from intraocular or systemic insults. It may develop in a diffuse pattern where the macula appears thickened or it may acquire the characteristic petaloid appearance referred to as cystoid macular edema. Although macular edema may be associated with various underlying conditions, it is most commonly seen following intraocular surgery, venous occlusive disease, DIABETIC RETINOPATHY, and posterior segment inflammatory disease. (From Survey of Ophthalmology 2004; 49(5) 470-90)
Separation of the inner layers of the retina (neural retina) from the pigment epithelium. Retinal detachment occurs more commonly in men than in women, in eyes with degenerative myopia, in aging and in aphakia. It may occur after an uncomplicated cataract extraction, but it is seen more often if vitreous humor has been lost during surgery. (Dorland, 27th ed; Newell, Ophthalmology: Principles and Concepts, 7th ed, p310-12).
Studies in which individuals or populations are followed to assess the outcome of exposures, procedures, or effects of a characteristic, e.g., occurrence of disease.
Hereditary, progressive degeneration of the neuroepithelium of the retina characterized by night blindness and progressive contraction of the visual field.
Enzymes that catalyze the rearrangement of geometry about double bonds. EC 5.2.
The distal part of the arm beyond the wrist in humans and primates, that includes the palm, fingers, and thumb.
Photosensitive afferent neurons located in the peripheral retina, with their density increases radially away from the FOVEA CENTRALIS. Being much more sensitive to light than the RETINAL CONE CELLS, the rod cells are responsible for twilight vision (at scotopic intensities) as well as peripheral vision, but provide no color discrimination.
Insertion of an artificial lens to replace the natural CRYSTALLINE LENS after CATARACT EXTRACTION or to supplement the natural lens which is left in place.
The measurement of magnetic fields over the head generated by electric currents in the brain. As in any electrical conductor, electric fields in the brain are accompanied by orthogonal magnetic fields. The measurement of these fields provides information about the localization of brain activity which is complementary to that provided by ELECTROENCEPHALOGRAPHY. Magnetoencephalography may be used alone or together with electroencephalography, for measurement of spontaneous or evoked activity, and for research or clinical purposes.
A procedure consisting of a sequence of algebraic formulas and/or logical steps to calculate or determine a given task.
A condition in which the intraocular pressure is elevated above normal and which may lead to glaucoma.
Observation of a population for a sufficient number of persons over a sufficient number of years to generate incidence or mortality rates subsequent to the selection of the study group.
A condition of an inequality of refractive power of the two eyes.
The tendency to perceive an incomplete pattern or object as complete or whole. This includes the Gestalt Law of Closure.
Unequal curvature of the refractive surfaces of the eye. Thus a point source of light cannot be brought to a point focus on the retina but is spread over a more or less diffuse area. This results from the radius of curvature in one plane being longer or shorter than the radius at right angles to it. (Dorland, 27th ed)
Semidomesticated variety of European polecat much used for hunting RODENTS and/or RABBITS and as a laboratory animal. It is in the subfamily Mustelinae, family MUSTELIDAE.
The gradual irreversible changes in structure and function of an organism that occur as a result of the passage of time.
A new pattern of perceptual or ideational material derived from past experience.
Auditory and visual instructional materials.
Paired bodies containing mostly GRAY MATTER and forming part of the lateral wall of the THIRD VENTRICLE of the brain.
Continuation of visual impression after cessation of stimuli causing the original image.
Photosensitive proteins in the membranes of PHOTORECEPTOR CELLS such as the rods and the cones. Opsins have varied light absorption properties and are members of the G-PROTEIN-COUPLED RECEPTORS family. Their ligands are VITAMIN A-based chromophores.
The dioptric adjustment of the EYE (to attain maximal sharpness of retinal imagery for an object of regard) referring to the ability, to the mechanism, or to the process. Ocular accommodation is the effecting of refractive changes by changes in the shape of the CRYSTALLINE LENS. Loosely, it refers to ocular adjustments for VISION, OCULAR at various distances. (Cline et al., Dictionary of Visual Science, 4th ed)
Involuntary movements of the eye that are divided into two types, jerk and pendular. Jerk nystagmus has a slow phase in one direction followed by a corrective fast phase in the opposite direction, and is usually caused by central or peripheral vestibular dysfunction. Pendular nystagmus features oscillations that are of equal velocity in both directions and this condition is often associated with visual loss early in life. (Adams et al., Principles of Neurology, 6th ed, p272)
The part of the cerebral hemisphere anterior to the central sulcus, and anterior and superior to the lateral sulcus.
The process by which the nature and meaning of tactile stimuli are recognized and interpreted by the brain, such as realizing the characteristics or name of an object being touched.
Function of the human eye that is used in dim illumination (scotopic intensities) or at nighttime. Scotopic vision is performed by RETINAL ROD PHOTORECEPTORS with high sensitivity to light and peak absorption wavelength at 507 nm near the blue end of the spectrum.
The surgical removal of the eyeball leaving the eye muscles and remaining orbital contents intact.
The function of opposing or restraining the excitation of neurons or their target excitable cells.
Examination of the interior of the eye with an ophthalmoscope.
An element with atomic symbol O, atomic number 8, and atomic weight [15.99903; 15.99977]. It is the most abundant element on earth and essential for respiration.
An order of the class Insecta. Wings, when present, number two and distinguish Diptera from other so-called flies, while the halteres, or reduced hindwings, separate Diptera from other insects with one pair of wings. The order includes the families Calliphoridae, Oestridae, Phoridae, SARCOPHAGIDAE, Scatophagidae, Sciaridae, SIMULIIDAE, Tabanidae, Therevidae, Trypetidae, CERATOPOGONIDAE; CHIRONOMIDAE; CULICIDAE; DROSOPHILIDAE; GLOSSINIDAE; MUSCIDAE; TEPHRITIDAE; and PSYCHODIDAE. The larval form of Diptera species are called maggots (see LARVA).
Disease of the RETINA as a complication of DIABETES MELLITUS. It is characterized by the progressive microvascular complications, such as ANEURYSM, interretinal EDEMA, and intraocular PATHOLOGIC NEOVASCULARIZATION.
A surgical specialty concerned with the structure and function of the eye and the medical and surgical treatment of its defects and diseases.
Swelling of the OPTIC DISK, usually in association with increased intracranial pressure, characterized by hyperemia, blurring of the disk margins, microhemorrhages, blind spot enlargement, and engorgement of retinal veins. Chronic papilledema may cause OPTIC ATROPHY and visual loss. (Miller et al., Clinical Neuro-Ophthalmology, 4th ed, p175)
Method of making images on a sensitized surface by exposure to light or other radiant energy.

Central visual, acoustic, and motor pathway involvement in a Charcot-Marie-Tooth family with an Asn205Ser mutation in the connexin 32 gene. (1/2272)

BACKGROUND: X linked dominant Charcot-Marie-Tooth disease (CMT1X) is an inherited motor and sensory neuropathy that mainly affects the peripheral nervous system. CMT1X is associated with mutations in the gap junction protein connexin 32 (Cx32). Cx32 is expressed in Schwann cells and oligodendrocytes in the peripheral (PNS) and in the (CNS) respectively. METHODS: A CMT1X family with a Cx32 mutation was examined clinically and electrophysiologically to determine whether PNS, or CNS, or both pathways were affected. RESULTS: In a CMT1X family a novel mutation (Asn205Ser) was found in the fourth transmembrane domain of Cx32. The patients showed typical clinical and electrophysiological abnormalities in the PNS, but in addition visual, acoustic, and motor pathways of the CNS were affected subclinically. This was indicated by pathological changes in visually evoked potentials (VEPs), brainstem auditory evoked potentials (BAEPs), and central motor evoked potentials (CMEPs). CONCLUSIONS: These findings underscore the necessity of a careful analysis of CNS pathways in patients with CMT and Cx32 mutations. Abnormal electrophysiological findings in CNS pathway examinations should raise the suspicion of CMTX and a search for gene mutations towards Cx32 should be considered.  (+info)

Action of the brain stem saccade generator during horizontal gaze shifts. I. Discharge patterns of omnidirectional pause neurons. (2/2272)

Omnidirectional pause neurons (OPNs) pause for the duration of a saccade in all directions because they are part of the neural mechanism that controls saccade duration. In the natural situation, however, large saccades are accompanied by head movements to produce rapid gaze shifts. To determine whether OPNs are part of the mechanism that controls the whole gaze shift rather than the eye saccade alone, we monitored the activity of 44 OPNs that paused for rightward and leftward gaze shifts but otherwise discharged at relatively constant average rates. Pause duration was well correlated with the duration of either eye or gaze movement but poorly correlated with the duration of head movement. The time of pause onset was aligned tightly with the onset of either eye or gaze movement but only loosely aligned with the onset of head movement. These data suggest that the OPN pause does not encode the duration of head movement. Further, the end of the OPN pause was often better aligned with the end of the eye movement than with the end of the gaze movement for individual gaze shifts. For most gaze shifts, the eye component ended with an immediate counterrotation owing to the vestibuloocular reflex (VOR), and gaze ended at variable times thereafter. In those gaze shifts where eye counterrotation was delayed, the end of the pause also was delayed. Taken together, these data suggest that the end of the pause influences the onset of eye counterrotation, not the end of the gaze shift. We suggest that OPN neurons act to control only that portion of the gaze movement that is commanded by the eye burst generator. This command is expressed by driving the saccadic eye movement directly and also by suppressing VOR eye counterrotation. Because gaze end is less well correlated with pause end and often occurs well after counterrotation onset, we conclude that elements of the burst generator typically are not active till gaze end, and that gaze end is determined by another mechanism independent of the OPNs.  (+info)

Functionally independent components of the late positive event-related potential during visual spatial attention. (3/2272)

Human event-related potentials (ERPs) were recorded from 10 subjects presented with visual target and nontarget stimuli at five screen locations and responding to targets presented at one of the locations. The late positive response complexes of 25-75 ERP average waveforms from the two task conditions were simultaneously analyzed with Independent Component Analysis, a new computational method for blindly separating linearly mixed signals. Three spatially fixed, temporally independent, behaviorally relevant, and physiologically plausible components were identified without reference to peaks in single-channel waveforms. A novel frontoparietal component (P3f) began at approximately 140 msec and peaked, in faster responders, at the onset of the motor command. The scalp distribution of P3f appeared consistent with brain regions activated during spatial orienting in functional imaging experiments. A longer-latency large component (P3b), positive over parietal cortex, was followed by a postmotor potential (Pmp) component that peaked 200 msec after the button press and reversed polarity near the central sulcus. A fourth component associated with a left frontocentral nontarget positivity (Pnt) was evoked primarily by target-like distractors presented in the attended location. When no distractors were presented, responses of five faster-responding subjects contained largest P3f and smallest Pmp components; when distractors were included, a Pmp component appeared only in responses of the five slower-responding subjects. Direct relationships between component amplitudes, latencies, and behavioral responses, plus similarities between component scalp distributions and regional activations reported in functional brain imaging experiments suggest that P3f, Pmp, and Pnt measure the time course and strength of functionally distinct brain processes.  (+info)

Frontal brain potentials during recognition are modulated by requirements to retrieve perceptual detail. (4/2272)

To assess the role of prefrontal cortex in retrieval and address the controversy about whether prefrontal retrieval operations are engaged only following successful retrieval, we recorded event-related brain potentials during two recognition tests with differing demands on retrieval effort. Both tests included object drawings that were (1) identical to those studied, (2) the same but with altered aspect ratios, and (3) previously unseen. Instructions were to respond "old" only if drawings were not modified (specific test) or regardless of modifications (general test). Frontal potentials were enhanced during the specific relative to the general test for all three types of drawings. We conclude that these potentials reflected differential engagement of strategic retrieval, that this function relied on left prefrontal cortex, and that it was not contingent on successful retrieval.  (+info)

Mid-peripheral pattern electrical retinal responses in normals, glaucoma suspects, and glaucoma patients. (5/2272)

AIMS: Reliance on intraocular pressure, optic nerve cupping changes, nerve fibre layer integrity, and visual field changes may delay treatment of glaucoma since irreversible changes may have already occurred at the time of diagnosis. Abnormal pattern electrical retinal responses (PERR or PERG) have been demonstrated in patients with ocular hypertension (no visual field changes) and glaucoma when visual stimulation was presented to the central field. Since glaucomatous visual field changes tend to occur first in the mid-periphery, the use of PERR outside of the central field may offer an earlier indication of glaucomatous involvement. METHODS: Glaucoma suspects and glaucoma patients were derived from a university practice. Normal subjects were recruited from non-patient volunteers. Alternating bar gratings were presented in the supranasal, supratemporal, infratemporal, and infranasal visual field. Six spatial frequencies, from 0.25 to 6.0 cycles per degree, were used for normal volunteers; three spatial frequencies, from 0.38 to 1.5 cycles per degree, were presented to suspects and glaucoma patients. Time of onset of the first negative (N35) and first positive peak (P50) and the amplitude consisting of the absolute difference between the first negative peak and first positive peak (P50 amplitude) are reported. Age corrected values were determined for normals, suspects, and glaucoma patients for each spatial frequency and for each quadrant in the visual field. RESULTS: Mean P50 amplitudes from normal subjects showed spatial tuning in all quadrants with reduced low frequency attenuation. Normals demonstrated a small decline in amplitude with age. Glaucoma patients demonstrated an age corrected reduction in amplitude and early implicit times. Glaucoma suspects had values between those of normal and glaucoma subjects. P50 amplitudes were weakly correlated with increasing cup to disc diameter ratio. A glaucoma patient with asymmetric visual field loss demonstrated significant diminution of the PERR bilaterally. CONCLUSION: The PERR, using mid-peripheral stimulation, may be a sensitive tool for the early detection of glaucoma. Further refinements can speed clinical data acquisition and enhance signal to noise ratio.  (+info)

Temporal analysis of the chromatic flash VEP--separate colour and luminance contrast components. (6/2272)

Temporal analysis of the chromatic flash visual evoked potential (VEP) was studied in human subjects with normal and anomalous colour vision using a deterministic pseudo-random binary stimulus (VERIS). Five experiments were carried out on four normal subjects investigating heterochromatic red-green exchange and single colour/achromatic (either red/grey or green/grey) exchange over a wide range of luminance ratios for the two stimuli, the effects of lowered mean luminance on the chromatic VEP and the effects of colour desaturation at constant mean luminance and constant luminance contrast. Finally, the performance of three dichromats, a protanope and two deuteranopes, on heterochromatic exchange VEP and on colour desaturation were investigated. In contrast to the chromatic electroretinogram, which shows great symmetry with respect to luminance ratio on opposite sides of the isoluminant point, the chromatic VEP demonstrated a distinct asymmetry when the colours exchanged included red. On the red side of isoluminance (red more luminant than green), a wave with longer latency and altered waveform became dominant. The effects of green stimulation were indistinguishable from those of achromatic stimulation at the same luminance contrast over the whole range of chromatic contrast and for all levels of desaturation studied. Desaturation of red with constant luminance contrast (desaturated red/grey stimulation) resulted in a systematic alteration in the evoked waveform. Subtraction of the achromatic first- and second-order responses from responses recorded in the red desaturation series resulted in remarkably uniform waveforms, with peak amplitudes growing linearly with saturation. The absence of interaction between achromatic and coloured components for all (including the most intense colour) stimulus parameters used suggests that the generators of these components are separate. Recordings from the dichromats showed that the contrast response minimum shifted from the point of photopic isoluminance to the point of zero cone contrast (at the silent substitution point) for the remaining cone type. The waveforms recorded with a series of luminance ratios were much simpler than those recorded from trichromats and symmetrical with respect to their isoluminant points. Despite the indication of the presence of L cones of apparently normal spectral sensitivity in the deuteranopes (on the basis of flicker photometry), there was no evidence for a red-sensitive component in the desaturation or heterochromatic stimulation series. The results are discussed in terms of the possibility of separate generation of chromatic and achromatic contributions to the VEP.  (+info)

Amodal completion in texture visual evoked potentials. (7/2272)

Amodal completion refers to the phenomenological finding of perceiving partly occluded objects as continuing uninterrupted behind an occluder. The outlying problem is how the visual system processes such non-local stimuli because the known processes of early vision are spatially restricted operations which segregate local differences in the visual image, and little is known about their interactions in producing the segmentation of the image into functionally coherent, or global, objects. We recorded human visual evoked potentials (VEPs) to texture stimuli and addressed local/non-local relationships in comparing a condition in which local edges were present, due to texture segregation, with a condition in which, in addition to local edges, textures appeared to continue as surfaces behind gray stripes due to non-local amodal completion. Subtraction of offset from onset responses showed: (1) a difference component due to texture segregation characterized by a negativity with onset at about 95 ms and lasting up to about 280 ms; (2) a further negativity, specifically elicited by amodal completion, with onset at about 142 ms, peaking at 175 ms, and lasting up to about 188 ms. Therefore, amodal completion occurs at an early processing stage of image analysis and the difference component in VEPs can be related to figure-ground perception.  (+info)

Effects of bicarbonate ion on chick retinal pigment epithelium: membrane potentials and light-evoked responses. (8/2272)

The purpose of this study was to determine how changes in [HCO3-] alter the electrical properties of the retinal pigment epithelium (RPE). Experiments were conducted on the isolated chick retina-RPE-choroid preparation. The chamber holding the preparation allowed independent perfusion of the retinal and the choroidal surfaces. The light-evoked trans-tissue potential (TTP), the trans-epithelial potential (TEP), the trans-retinal potentials, and the intracellularly-recorded apical and basal membrane potentials were studied. Increasing the [HCO3-]0 in the choroidal bath from 25 to 40 mEq/1 led to an increase in the TTP and TEP. The same change in the retinal bath decreased the TTP because of a biphasic change of the RPE membrane potentials. There was also an increase in the amplitudes of the TEP, the c-wave and the slow PIII. The light-evoked subretinal K+ decrease was greater which is consistent with an increase in the photoreceptor light response. These observations indicated that the decrease of TTP resulted from a basal membrane hyperpolarization followed by an apical membrane depolarization induced by an increase in retinal [HCO3-]0. The relationship of these potential changes to the human bicarbonate responses is discussed.  (+info)

Purpose : Our previous work affirmed that in glaucoma paired eyes and brain work together to maximize the binocular field, avoiding overlapping areas of visual loss (the Jigsaw Effect; TVST 2013,14). We also observed that among glaucomatous eyes with either high(85%; Hc) or low(15%; Lc) contrast VEP latency in each eye showed a strong inverse relationship (P=0.0000003) between Hc and Lc latency between the paired eyes, presumably conserving binocular dynamic function (Ly et al ARVO 2017). We sought to determine whether central vs midperipheral visual field loss tended to correspond with bilateral Hc/Lc functional bias. Methods : 30 paired glaucomatous eyes that each demonstrated either Hc or Lc latency abnormality on SD-tVEP (Diopsys, Inc, Pine Brook, NJ) underwent masked assessment of recent paired visual fields (HVFA or FDT) to determine whether field loss was dominantly central (C), peripheral (P), or normal (N). Binary analysis of Hc and Lc versus C and P was performed. Results : 60 eyes ...
The multifocal visual evoked potential (mfVEP) is largely generated in V1. To relate the electrical activity recorded from humans to recordings from single cells in nonhuman primate (V1) cortex, contrast-response functions for the human mfVEP were compared to predictions from a model of V1 activity (D. J. Heeger, A. C. Huk, W. S. Geisler, & D. G. Albrecht, 2000) based upon single-cell recordings from monkey V1 (e.g., D. G. Albrecht, 1995; D. G. Albrecht, W. S. Geisler, R. A. Frazor, & A. M. Crane, 2002; D. G. Albrecht & D. B. Hamilton, 1982; W. S. Geisler & D. G. Albrecht, 1997). A second purpose was to fully articulate the assumptions of this model to better understand the implications of this comparison. Finally, as the third purpose, one of these assumptions was tested. Monocular mfVEPs were obtained from normal subjects with a contrast-reversing dartboard pattern. The display contained 16 sectors each with a checkerboard. Both the sectors and the checks were scaled approximately for cortical ...
VEPs were recorded with three different spatial frequencies of stimulation in patients affected by idiopathic Parkinsonism and by Parkinsonian syndromes. The detection of VEP abnormalities in Parkinsons disease was dependent on the spatial frequency of the visual stimulus (a vertical square wave grating). The VEP latency was normal in Parkinsonian syndrome patients (except in one patient affected by familial Parkinsonism). Dopamine precursor therapy differently reduced the VEP latency, depending on the spatial frequency of the visual stimulus. These findings suggest that the dopaminergic mechanism involved in the generation of VEP delays is sensitive to stimulus spatial frequency. The study of VEPs before and after the administration of haloperidol confirmed this hypothesis. VEP latency did not correlate with the major clinical symptoms of Parkinsons disease and could not predict the results of chronic dopaminergic therapy.. ...
To reach and grasp an object in space on the basis of its image cast on the retina requires different coordinate transformations that take into account gaze and limb positioning. Eye position in the orbit influences the images conversion from retinotopic (eye-centered) coordinates to an egocentric frame necessary for guiding action. Neuroimaging studies have revealed eye position-dependent activity in extrastriate visual, parietal and frontal areas that is along the visuo-motor pathway. At the earliest vision stage, the role of the primary visual area (V1) in this process remains unclear. We used an experimental design based on pattern-onset visual evoked potentials (VEP) recordings to study the effect of eye position on V1 activity in humans. We showed that the amplitude of the initial C1 component of VEP, acknowledged to originate in V1, was modulated by the eye position. We also established that putative spontaneous small saccades related to eccentric fixation, as well as retinal disparity cannot
ANTIARRHYTHMICS piromecaine use BUMECAINE was PIROMECAINE PIROMIDATE h. PERG amplitude (ordinate, as derived from befтre inset traces) versus check size (quantified as dominant spatial frequency, large checks left).
Looking for online definition of alternating checkerboard stimulus in the Medical Dictionary? alternating checkerboard stimulus explanation free. What is alternating checkerboard stimulus? Meaning of alternating checkerboard stimulus medical term. What does alternating checkerboard stimulus mean?
ObjectiveTo determine if sweep visual evoked potential (VEP) acuity is predictive of recognition acuity in children with albinism.MethodsA retrospective review
We investigated a means to measure visual acuity in awake mice using visually evoked potentials (VEPs). Using counter-phasing sinusoidal gratings as stimuli, we compared the effectiveness of vertical and horizontal orientations in generating VEPs. Using stereotaxic implanted electrodes in the animals primary visual cortex, the evoked VEPs were recorded and analyzed. At the lowest spatial frequency, vertical stimuli evoked the largest VEP amplitude. However, at higher spatial frequencies, a reversal occurs where horizontal gratings evoked larger VEPs. These data suggest vertical and horizontal stimuli have different effects on generating VEPs although further investigation is required to determine which stimulus is most suitable for measuring visual acuity in mice. Uncovering this relationship will also help us to understand the link between physiological activity of the brain and behavioral function.
Microsoft Visual C# 2008 (MS Visual C# 2008) allows Visual C# 2008 programmers to rapidly create Windows applications for their end users. (C# is pronounced c-sharp). Visual C# 2008 developers can extend the standard functionality available inside the Visual C# 2008 IDE with a variety of Visual C# 2008 add-ins and Visual C# 2008 tools. The extensibility of Visual C# 2008 is one of the main reasons it has proved to be popular with developers, as Visual C# 2008 software engineers can find Visual C# 2008 downloads from other companies or other VC# developers to act as a Visual C# 2008 extension to their Visual C# 2008 IDE or Visual C# 2008 app.. The versatility of Visual C# 2008 also extends to various forms of Visual C# 2008 software components. Visual C# 2008 controls can be used to create feature rich Visual C# 2008 user interfaces on forms and Web pages inside Visual C# 2008 apps. These Visual C# 2008 UI controls are augmented by non-visual Visual C# 2008 components or Visual C# 2008 libraries ...
Substitute methadone is the currently recommended treatment of pregnant opioid-dependent women.23 Several observational studies have reported abnormalities of visual and neurologic development in infants of drug-misusing mothers prescribed substitute methadone in pregnancy,5-12,17 but to date there has been no prospective study of such infants, and so the prevalence of visual dysfunction in this population remains unknown.. We have previously described abnormal flash VEPs in newborn infants exposed to methadone in utero17 but these data were confounded by IUGR and gestation, and numbers were too small to investigate the individual effects of methadone and other illicit drugs. This larger cohort study has confirmed substantial differences between neonatal flash VEPs of infants exposed to methadone in utero and those of non-drug-exposed comparison infants and suggests that prescribed substitute methadone, rather than other illicit drugs, may be to blame. Reduced VEP amplitude with immature ...
Diabetes mellitus (DM) is a metabolic disorder which is characterised by hyperglycaemia resulting from defects in insulin secretion, insulin action or both. The long-term specific effects of DM include the development of retinopathy, nephropathy and neuropathy. Cardiac disease, peripheral arterial and cerebrovascular disease are also known to be linked with DM. Type 1 diabetes mellitus (T1DM) accounts for approximately 10% of all individuals with DM, and insulin therapy is the only available treatment. Type 2 diabetes mellitus (T2DM) accounts for 90% of all individuals with DM. Diet, exercise, oral hypoglycaemic agents and occasionally exogenous insulin are used to manage T2DM. The diagnosis of DM is made where the glycated haemoglobin (HbA1c) percentage is greater than 6.5%. Pattern-reversal visual evoked potential (PVEP) testing is an objective means of evaluating impulse conduction along the central nervous pathways. Increased peak time of the visual P100 waveform is an expression of ...
88 eyes of 48 consecutive patients were included for study, 20 male and 28 female, aged 57-94 (avg. 79). All patients had glaucomatous optic nerve cupping and/or glaucomatous visual field loss prior to treatment. Pretreatment, IOPs ranged 6-23mm Hg (avg. 13) on 0-3 (avg. 1.6) medications. 33 eyes had had prior glaucoma surgery. Snellen visual acuities (VA) ranged 20/15 to count fingers (median 20/60). Prior to treatment, both VEPs and ORPs of all eyes were abnormal. Following panmacular SDM, VA and IOP were unchanged, while VEP amplitudes (p=0.001) and automated perimetry by ORP ( ...
松岡 洋夫 , 中村 真樹 精神神經學雜誌 = Psychiatria et neurologia Japonica 107(4), 307-322, 2005-04-25 医中誌Web 参考文献58件 被引用文献2件 ...
Visual stimulation of babies taken to a whole new scientific level Stimulate your baby and learn about the stages of developmentbrbrThis app will automatically select visuals that fit the specific stage in your childs mental and physical
english 1010 visual analysis essay tamaralang, visual analysis, elements and principles of design ppt video online download, what your visitors see 3 types of visual analysis tools, visual analysis rhetoric composition i
What type of investigation is done in the Visual Regression Testing market report?. Analysis of various socioeconomics for venturing into the market is important as it will hugely affect the development throughout the following coming years. The Visual Regression Testing market report is planned subsequent to doing long periods of exploration and the information sifted through in the report was gathered from dependable sources, for example, government sites.. As the market is gigantic, it turns out to be imperative to comprehend the market from its underlying foundations. Get a superior perspective on the Visual Regression Testing market through the data referenced in the committed areas of the report. With this, the customers likewise get a perspective on the business structure of the contenders.. What are the reasons that impact the growth of the Visual Regression Testing Market?. As of late, the advanced transformation has pushed the associations in changing into a computerized business for ...
The test was initially written by Matteo Bruni https://www.winehq.org/pipermail/wine-patches/2015-April/138974.html but rejected as failed https://www.winehq.org/pipermail/wine-devel/2015-April/107491.html I modified those patch and rebase for wine-1.7.43-166-g39d71c5 Now log looks as follow before patch for levels -- visual.c:18561: Test failed: Unexpected result on update texture, hr 0, should fail, case 0, 8. visual.c:18568: Test marked todo: Failed to update texture, hr 0x8876086c, case 0, 11. visual.c:18568: Test marked todo: Failed to update texture, hr 0x8876086c, case 0, 12. visual.c:18568: Test marked todo: Failed to update texture, hr 0x8876086c, case 0, 13. visual.c:18568: Test marked todo: Failed to update texture, hr 0x8876086c, case 0, 14. visual.c:18568: Test marked todo: Failed to update texture, hr 0x8876086c, case 0, 15. visual.c:18561: Test failed: Unexpected result on update texture, hr 0, should fail, case 1, 8. visual.c:18568: Test marked todo: Failed to update texture, hr ...
This example shows the separation results for a marble tile for different resolutions of imaging and illumination. For scale = 1, the resolution of the camera was set at the native resolution of 1024x768 and the separation was done with a checkerboard pattern with checkers of 4x4 projector pixels. For lower scales of 1/n, the resolution of the camera was reduced by aggregating n x n pixels and the checker size of the illumination pattern was increased to 4n x 4n. The images shown above correspond to scales 1, 1/2, 1/4 and 1/6 from top to bottom. At scale = 1, we see a slight direct component and a dominant global component. In contrast, at scale = 1/6, we see that the global component is nearly zero everywhere and the direct component is almost equal to the original image. This example shows how the BSSRDF of a translucent object dominates at fine scales, but reduces to a BRDF as one goes to coarser scales ...
visual synonyms: adjective Serving, resulting from, or relating to the sense of sight: optic, optical. See see Capable of being seen: discernible, perceivable, perceptible, seeable, viewable, visible. See see ...
SAS Visual Statistics combines a visual interface and in-memory processing so users can create and modify predictive models to meet business requirements.
Hi ,. Im using VEP (in local query database) to annotate my vcf in my pipeline. I was looking for parameter concerning the distance base from the splicing site used by VEP for call a variant as splicing effect ? I didnt found the information in the doc.. Best Tristan ...
dlls/d3d8/tests/visual.c , 283 ++++++++++++++++++++++++++++++++++++++++++++++ 1 files changed, 283 insertions(+), 0 deletions(-) diff --git a/dlls/d3d8/tests/visual.c b/dlls/d3d8/tests/visual.c index d8e1ed2..068b559 100644 --- a/dlls/d3d8/tests/visual.c +++ b/dlls/d3d8/tests/visual.c @@ -629,6 +629,287 @@ static void fog_test(IDirect3DDevice8 *device) ok(hr == D3D_OK, Turning off fog calculations returned %#08x\n, hr); } +/* This tests fog in combination with shaders. + * Whats tested: linear fog (vertex and table) with pixel shader + * linear table fog with non foggy vertex shader + * vertex fog with foggy vertex shader, non-linear + * fog with shader, non-linear fog with foggy shader, + * linear table fog with foggy shader */ +static void fog_with_shader_test(IDirect3DDevice8 *device) +{ + HRESULT hr; + DWORD color; + union + { + float f; + DWORD i; + } start, end; + unsigned int i, j; + + /* Basic vertex shader without fog computation (non foggy) */ + static const DWORD ...
I just have a question about my VEP report. I went to the hospital yesterday to pick up a copy of my results (my neuro said it was normal but I wanted a copy). First of all they told me that my neuro a...
Maximize muscle tone and gain strength by training your nervous system with frequent low volume workouts. Visual Impact Frequency Training by Rusty Moore.
Maximize muscle tone and gain strength by training your nervous system with frequent low volume workouts. Visual Impact Frequency Training by Rusty Moore.
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Buy Blood Splatter Pack by CG_Visuals on VideoHive. 50 Blood & Gore Assets, with alpha channel. Split across 4 Categories: Blood on Lens, Extreme Gore, Fatal Injurie...
Visual Apex has great deals on Da-Lite Advantage Deluxe Electrol projector screen for $2,720 and other Da-Lite Projector Screens.
3 Whenever possible, accents should be visually framed. This can be accomplished by placing the feature of emphasis in a proper position to be viewed through a visual
These screen-free activities are ideal for kids who are stuck at home during COVID-19. Theyre designed to provide an alternative to excessive screen time and build visual skills in the process.
Study Flashcards On Acute_Visual_Loss at Cram.com. Quickly memorize the terms, phrases and much more. Cram.com makes it easy to get the grade you want!
Asistenti medicali generalisti - tehnici de nursing amg, anatomie si articole medicale pentru elevii scolilor postliceale sanitare, studentii facultatilor de profil, asistenti medicali generalisti
There was an EDC thread a while back but its lacking in visuals. SUFUs got a thread like this but Id like to see SFs take. Post pictures of your...
PRINT (founded 1940) is where creative people gather to inspire and build design dialogue. Perpetually curious about everything design, we report on, curate and celebrate visual culture, the makers of that culture and the expression of graphic design in all its forms and mediums. ...
120), 1965. Sbgh. Appropriate development and function of the retinal vas- culature are also critical for maintaining proper visual func- tion.
TY - GEN. T1 - Innovative pattern reversal displays for visual electrophysiological studies. AU - Toft-Nielsen, J.. AU - Bohorquez, Jorge. AU - Ozdamar, Ozcan. PY - 2011/12/26. Y1 - 2011/12/26. N2 - Pattern Reversal (PR) stimulation is a frequently used tool in the evaluation of the visual pathway. The PR stimulus consists of a field of black and white segments (usually checks or bars) of constant luminance, which change phase (black to white and white to black) at a given reversal rate. The Pattern Electroretinogram (PERG) is a biological potential that is evoked from the retina upon viewing PR display. Likewise, the Pattern Visual Evoked Potential (PVEP) is a biological potential recorded from the occipital cortex when viewing a PR display. Typically, PR stimuli are presented on a Cathode Ray Tube (CRT) or Liquid Crystal Display (LCD) monitor. This paper presents three modalities to generate pattern reversal stimuli. The three methods are as follows: a display consisting of array of Light ...
Purpose: : Glaucoma diagnosis and management is based on the assessment of optic nerve structure and function. The conventional pattern-reversal visual evoked potential (VEP) technique has been used as an objective method of evaluating the visual pathway. We investigated the correlation between structural and functional damage in patients with asymmetric glaucoma using a fast transient VEP (ftVEP) device. Methods: : Twenty-three subjects with bilateral glaucoma (glaucomatous optic neuropathy + visual field defects) and visual acuity ≥ 20/25 underwent optical coherence tomography (Stratus OCT) for macular thickness measurement, scanning laser polarimetry with variable corneal compensation (GDx-VCC) for RNFL measurement and ftVEP (Diopsys, Inc., Pine Brook, NJ; 10 and 85% Michelson of contrast, acquisition time of 20s) in both eyes within 2 months. Asymmetric glaucoma was defined as a difference in MD of at least 3 dB (SITA Standard 24-2). The correlation between structural test results (OCT and ...
Advanced Visual FoxPro To PDF Table Converter is a utility that allows execution of SQL (Structured Query Language) statements on DBF database files. Resultsets returned by select queries are automatically persisted as PDF files to a directory of your choice. Advanced Visual FoxPro To PDF Table Converter provides user interface to define PDF table column headers, PDF document page size, PDF document page orientation, PDF table font type and PDF table font size. In addition to this, the application automatically persists most recently used output directory path and allows assignment of custom names to output PDF files Convert Visual FoxPro to PDF Convert Visual FoxPro to PDF table Convert Visual FoxPros files to PDF tables Convert Visual FoxPro tables to PDF tables Convert Visual FoxPro databases to PDF tables Export Visual FoxPro to PDF Export Visual FoxPro to PDF table Export Visual FoxPro files to PDF tables Export Visual FoxPro tables to PDF tables Export Visual FoxPro databases to PDF tables ...
Sensory information processing in ACC networks is critical for ACC-related brain functions. Using in vivo whole-cell recording, we have investigated MP responses of layer II/III ACC neurons to sensory stimulation. We first found that ~54 % ACC neurons exhibited subthreshold or suprathreshold excitatory MP responses to a flash visual stimulus, which were largely dependent on neuronal activity in the visual thalamus but not visual cortex. We further found in an even larger population (~81 %) of ACC neurons that excitatory MP responses could also be evoked by a pain-related electrical stimulus. These findings may reflect potential mechanisms underlying the ACC function that involves information processing of sensory and noxious stimuli.. As a multimodal brain region, ACC has been known to be capable of responding to complex stimulation or tasks, including those related to reward [21-23] and aversive stimuli [7, 24-26] as well as attention [1, 9, 10, 27]. However, ACC neuronal activity in response ...
25 Contour plot of interocular asymmetry indexes across the age span as a function of latency of the luminance flash VEP response is depicted (upper asymmetry contour plot). His- tologically these tumors are comprised of large, polygonal cells with vesicular nuclei. Int J Pharm 1993; 89223в228. V.
Thus the individual endures a double burden ava ilable painвboth from the sense of loss (often unconscious) and from what subsequently becomes an attack on her or his own ego, which now generic in place of the loved object. Flicker threshold and pattern VEP latency in ocular hypertension and glaucoma.
Visual Evoked Potentials (VEPs) are used in clinical applications in ophthalmology, neurology and extensively in brain computer interface (BCI) research. BCI literature covers steady state VEP (SSVEP) and code modulated VEP (c-VEP) BCIs along with sophisticated methods to improve information transfer rates (ITR). There is a gap of knowledge regarding the VEP adaptation dynamics, physiological generation mechanisms and relation with BCI performance. A simple dual display VEP switch was developed to test signatures elicited by non-isochronic, non-singular, low jitter stimuli at the rates of 10, 32, 50 and 70 reversals per second (rps). Non-isochronic, low-jitter stimulation elicits Quasi-Steady-State VEPs (QSS-VEPs) that are utilized for simultaneous generation of transient VEP and QSS-VEP. QSS-VEP is a special case of c-VEPs and it is assumed that it shares the similar generators of the SSVEPs. Eight subjects were recorded and the performance of the overall system was analyzed by means of Receiver
A portable device for detecting multifocal steady-state visual evoked potentials associated with visual field stimulation is being developed as an objective test for identifying glaucoma-related visual function loss.
In adults, certain regions of the brains visual cortex respond preferentially to specific types of input, such as faces or objects-but how and when those preferences arise has long puzzled neuroscientists.
Many researchers have taken the Colavita effect to represent a paradigm case of visual dominance. Broadly defined, the effect occurs when people fail to respond to an auditory target if they also have to respond to a visual target presented at the same time. Previous studies have revealed the remarkable resilience of this effect to various manipulations. In fact, a reversal of the Colavita visual dominance effect (i.e., auditory dominance) has never been reported. Here, we present a series of experiments designed to investigate whether it is possible to reverse the Colavita effect when the target stimuli consist of repetitions embedded in simultaneously presented auditory and visual streams of stimuli. In line with previous findings, the Colavita effect was still observed for an immediate repetition task, but when an n-1 repetition detection task was used, a reversal of visual dominance was demonstrated. These results suggest that masking from intervening stimuli between n-1 repetition targets was
In article ,CIpGxt.BGH at umdnj.edu, bawagan at umdnj.edu (Hinayana Bawagan) writes: , , I find it a pain to run RNA formaldehyde gels. Even with 3 uls of RNA, I ,get the faintest signal. Theres an article in Biotechniques that describes the best way to see RNA with ethidium. I think its from within the last 2 years or so (maybe Jan. 91) and one of the authors is Gong. , I can use 0.5% TBE agarose gel but my problem is with DNA markers, I can ,only say that my RNA migrates with this band of DNA. Can I do something to ,the DNA markers that will make them run like a ss RNA? Has anyone out there ,establish that a single-stranded RNA of a particular size migrates with ,DNA of a particular size? Many companies sell RNA markers. I have used the ones from BRL, which work well. Hope this helps. -- -Barry (bjmarg at welchlink.welch.jhu.edu ...
Common Pediatric Vision Tests and Eye Procedures at our hospital uses child-focused, high tech diagnostics including ERG and Sweep Visual Evoked Potential.
Manufacturer of Visual Testing System - Visual Acuity Testing System, Vision Testing Drums offered by Plantech Medical Systems Private Limited, Ahmedabad, Gujarat.
Search Visual associate jobs. Get the right Visual associate job with company ratings & salaries. 33,633 open jobs for Visual associate.
None of the online businesses can survive in the industry if they dont establish a brand of themselves. It is going to be very easy for a company to become successful in their business if they are branded.. Branding denotes that you company has a name and reputation amid people. Branding indicates the usefulness, usability and reliability. So, people will always come after your products, services and company for their different purposes.. Without a doubt, there are a lot of things that influences branding of a company or website online and one among them is visual design. People will admire a website and rate it as superior if they find its design is exceptional. In general, visual design is the utilization of imagery, shapes, typography, color, and also form with the aim of boosting usability, effectiveness and getting better the user experience. It is a fact that visual design has as a great deal of influence and effect on the overall experience and usefulness, usage, and usability. So, when ...
A visual parking guide, more particularly, a thin flat surface, divided into three zones, with a multitude of markings in each zone, to assist drivers of varying heights to park their car in a safe parking position. The visual parking guide is mountable on a supporting structure such that at least a portion of the parking guide is within the field of view of the driver. By parking the vehicle at a preferred distance from a stationary structure and aligning a fixed point relative to the vehicle with one of the multitude of markings on the visual parking guide, the driver can determine a reference point to use as a means to determine the safe parking position.
While at Comdex, Visual Basic author and presenter, Paul Kimmel, was asked the question, Where is Visual Basic 7? Paul helps to alleviate the concerns that Microsoft has abandoned Visual Basic.
to specify which visual gears get drawn on top. Most visual gears delete themselves eventually. NOTE: Visual gears must only be used for decorational/informational/rendering purposes. Never use the visual gears internal state to manipulate anything gameplay-related. Visual gears are not safe for reliable storage and using them as that would lead to strange bugs. NOTE: Since 0.9.25, visual gears will never spawn when Hedgewars is run in a testing mode (i.e. not as the real game), so dont rely for visual gears to spawn even if theyre critical. Example: ...
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Visual representations are just as complex and often more cryptic than textual images. Never underestimate the richness of pictures. Give yourself plenty of time to complete this assignment. You will be asked to look carefully, think analytically and justify all your observations. Here are the two steps to this exercise:. 1. Review How to Prepare Visual Primary Sources. Follow the instructions as you review the below images. Write down your responses to the questions as you move through the Web site. These will be collected and graded. Remember, explanatory blurbs are nice but the goal here is to learn to describe and interpret what you see ...
In the department specialized in Visual Quality we treat all the alterations that affect the visual quality. Read all the information.
Graphs are a visual treat, as they can present complex information in a quick and easy manner. Mostly graphs are used to reveal a trend, compare statistics or they can be even used to establish relationship between two different variables.There are several types of graphs and each graph has different display properties to represent the data. Based on the information, choose a graph that depicts data in an effective way.This infographic shares some interesting information about different graph types. | visual data
...The most basic lesson we learn first in my visual design class is that slides are not documents. In order to create slides that use the Keynote or PowerPoint medium as it was intended to be used - for a visual purpose - we must set up our slides for success. | Digital Presentations in Education
Oral cancer surgery : a visual guide , Oral cancer surgery : a visual guide , کتابخانه الکترونیک و دیجیتال - آذرسا
Describes information about Visual Studio 2010 Service Pack 1 (SP1). Additionally, this article lists the fixed issues and added technology enhancements in Visual Studio 2010 SP1.
The Softain Biopsy - Visual Assignment 305: ReCaptcha Illustrated , originally uploaded by Rowan Peter. The Softain Biopsy The Softain Biopsy is a medical procedure performed by specialist surgeon Dr Sigmeund Softain involving sampling of diseased human cells or tissues for examination, repair, duplication and then re-insertion back into the patient. Visual Assignment 305: ReCaptcha…
This study discusses the combined effect of auditory and visual factors on comprehensive comfortableness. We used the concept of harmonious sensation to explain this effect. To clarify the function of this sensation, we conducted two psychological experiments. The result shows that harmonious sensation, visual and auditory comfortableness has an equal influence on comprehensive comfortableness. The effect of harmonious sensation was varied according to the degree of visual and auditory comfortableness; This effect increased as the difference in the degree of comfortableness between visual and auditory factors becomes wide.. ...
What is the oblique effect? Some say that humans living in large cities are experiencing a form of selective rearing in that we don t encounter many oblique lines in our environment. Briefly describe the experiment discussed in class which was designed to examine this question. What conclusions were made from this experiment ...
Visual SLAM (simultaneous localization and mapping) refers to the problem of using images, as the only source of external information, in order to establish the position of a robot, a vehicle, or a mo
Provide effective wound care with skill and confidence, with the expert direction and real-life images of the fully updated Wound Care Made Incredibly Visual!®, 3rd Edition.
This course provides an overview of SAS Visual Investigator and teaches you to navigate the user interface and perform investigations.
05/24/18 - Real-time detection of irregularities in visual data is very invaluable and useful in many prospective applications including surv...
SAS Visual Statistics combina interfaccia grafica ed elaborazione in-memory: consente di creare e modificare modelli predittivi secondo i requisiti di business.
Configure visual studio load testing tool and utilize to scale application by analyzing testing results; Author: Shahriar Iqbal Chowdhury/Galib; Updated: 9 Aug 2012; Section: ASP.NET; Chapter: Web Development; Updated: 9 Aug 2012
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Continuous delivery is the logical evolution of agile. In this course, youll learn how you can make the concepts of continuous delivery come true in a practical way using Visual Studio, TFS/VSTS, Release Management, Docker, and Application Insights.
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Sudden announcements appear on Siren Visuals Facebook with Chihayafuru Season 2, The Devil is a Part Timer and Queens Blade Rebellion to be released in 2014;
And there is not calmly maintain the online objective c visual quickstart shoulders for the intensity and the because there are policy of Italian, few, clear costs often that are known altogether only. The superficial handlers insist the Polish viruses a third market. region and big attack.
Visual Lizard is dedicated to web standards and accessibility. We build web applications and program in CSS, PHP and valid xHTML 1 strict.
Visual motifs do all the heavy lifting in any print ad. Heres a few ways to better use them to you advantage on your print materials.
SQL Server 2008 R2, Windows Server 2008 R2, and Visual Studio 2010 will be the last major versions to support Intels Itanium processor. While extended support will be offered for 8 years, new investm
Visual Lizard is dedicated to web standards and accessibility. We build web applications and program in CSS, PHP and valid xHTML 1 strict.
I want to set multi site setup in Visual studio for multiple sites in Sitecore. I want to have separate Layouts/sublayouts/ascx and code behind for all websites. Also i want separate config files for each website so that it will be easy to update individual sites. i didnt find any appropriate documentation from web.. Any help ...
Grisaia no Kajitsu (known as The Fruit of Grisaia in the West) is a visual novel released by frontwing in 2011. Growing restless with his unspecified but …
For more information on VEP intensivist management, contact Dr. Kevin Park, Chief of Pulmonary and Critical Care Services: [email protected] ...
In this invented new input method, a new input scenario for stroke-based Chinese input is proposed . When using this method , the input of Chinese chara...
We developed this information graphic to illustrate the educational challenges our client faces and to present a compelling case for support to prospe
May include visual, auditory, or somatosensory evoked potentials. These record the electrical responses of the brain and spinal ... EMG and evoked potentials, and electrodiagnostic physician focuses mainly on nerve conduction studies, needle EMG, and evoked ... Evoked potentials: Diagnostic test evaluating specific tracts of the central and peripheral nervous system. ... Physiologists perform the majority of EEGs, evoked potentials and a portion of the nerve conduction studies. They are then ...
Electrooculography Visual evoked potential Perlman, Ido. "The Electroretinogram: ERG by Ido Perlman". Webvision at University ... The ERG is composed of electrical potentials contributed by different cell types within the retina, and the stimulus conditions ... The pattern ERG (PERG), evoked by an alternating checkerboard stimulus, primarily reflects activity of retinal ganglion cells. ... 2005). "An overview of drug development with special emphasis on the role of visual electrophysiological testing". Doc. ...
Van Voorhis, S. T.; Hillyard, S. A. (1977). "Visual evoked potentials and selective attention to points in space". Perception ... Von Voorhis and Hillyard (1977) used an EEG to observe event-related potentials (ERPs) of visual stimuli. Participants were ... The hierarchical system of analysis is one of maximal economy: while facilitating the potential for important, unexpected, or ... Results demonstrated that when attending to visual stimuli, the amount of voltage fluctuation was greater at occipital sites ...
Thomas NG, Harden LM, Rogers GG (September 2005). "Visual evoked potentials, reaction times and eye dominance in cricketers". ... Ocular dominance, sometimes called eye preference or eyedness, is the tendency to prefer visual input from one eye to the other ... The study suggests this difference may be a potential, and possibly treatable, cause of dyslexia; however, further tests are ... Pointer JS (January 2007). "The absence of lateral congruency between sighting dominance and the eye with better visual acuity ...
There could be an abnormal electroretinogram or visual evoked potentials. Neuron-specific enolase and axonal heavy chain ... Examination reveals decreased visual acuity, loss of color vision and a cecocentral scotoma on visual field examination. "LHON ... as potential triggers of visual loss similar to smoking or excessive alcohol consumption. Hormone replacement therapy (HRT) is ... Clinically, there is an acute onset of visual loss, first in one eye, and then a few weeks to months later in the other. Onset ...
"O52 Visual evoked potentials and electroretinography in brain-dead patients". Neurophysiologie Clinique/Clinical ... Patients have low visual acuity and fail to fixate to the visual stimuli. Depends on the severity, some display no visual ... Although ocular abnormalities account for the poor vision to a large extend, some of the visual problems is associated with the ... Assessment of motor and mental development, visual ability also provide clues. Genetic test can analyze the genome of infants ...
"A high-speed brain speller using steady-state visual evoked potentials". International Journal of Neural Systems. 24 (6): ... and improving human-robot communication via rapid series visual presentations with EEG. CaN was made possible by the ...
A. Vrca; V. Bozikov; Z. Brzović; R. Fuchs; M. Malinar (September 1996). "Visual evoked potentials in relation to factors of ... After release from segregated housing, psychological effects have the ability to sabotage a prisoner's potential to ...
"Neurophysiological assessment through visual evoked potentials and tensiomyography on multiple sclerosis patients." Šimunič, B ...
These brain responses can be examined using visual and sensory evoked potentials. Therefore, clinical data alone had to be used ... The most commonly used diagnostic tools at that time were evoked potentials. The nervous system of a person with MS responds ... Gronseth GS, Ashman EJ (May 2000). "Practice parameter: the usefulness of evoked potentials in identifying clinically silent ...
2001). Visual evoked potentials to infrared stimulation in normal cats and rats. Documenta Ophthalmologica 103:155-162. Silva ... Investigative Ophthalmology and Visual Science 58:2863-73. Parthasarathy R, Chow KM, Derafshi Z, Fautsch MP, Hetling JR, ... Investigative Ophthalmology and Visual Science 45(7):2447-56. Hetling JR & Baig-Silva MS. (2004). Neural prostheses for vision ... Hetling JR, Baig-Silva MS, Comer CM, Pardue MT, Samaan DY, Qtaishat NM, Pepperberg DR & Park TJ (2005). Features of visual ...
BCIs that Use Steady-State Visual Evoked Potentials or Slow Cortical Potentials. In: Brain-Computer Interfaces: Principles and ... BCIs that rely on steady state visual evoked potentials (SSVEPs) instead rely on items that flicker instead of flash. The user ... If the user's visual areas show an increase at 8 Hz and its harmonics, a signal processing algorithm can identify this spike ... Therefore, a BCI can determine the target item by identifying the peak frequencies in the user's visual areas, which can only ...
These brain responses can be examined using visual- and sensory-evoked potentials. To get a diagnosis of CDMS a patient must ... Gronseth GS, Ashman EJ (May 2000). "Practice parameter: the usefulness of evoked potentials in identifying clinically silent ... The most commonly used diagnostic tools are neuroimaging, analysis of cerebrospinal fluid and evoked potentials. Magnetic ...
2005] analyzed the visual evoked potentials of macaque performing visual spatial attention task. Epidemiology: Cummings et al ... "Time-frequency spectral analysis of TMS-evoked EEG oscillations by means of Hilbert-Huang transform". J Neurosci Methods. 198 ( ...
However, visual evoked potentials do play a role in the whole diagnostic process. Parkinson's disease is a degenerative ailment ... In such cases, the application of a stimulus to the desired target can produce transient evoked potentials that can provide ... Although the development of MRI has allowed for very effective detection of brainstem lesions, evoked potentials measurements ... EMG measures action potentials, called Motor Unit Action Potentials (MUAPs), created during muscle contraction. A few common ...
Izmailov Ch.A., Korshunova S.G., Sokolov E.N. Human visual evoked potentials to change in the emotional expression of a ... Izmailov Ch.A., Korshunova S.G., Sokolov E.N. Relationship between visual evoked potentials and subjective differences between ... A., Korshunova S. G., Sokolov E. N. (2001). Relationship between visual evoked potentials and subjective differences between ... A., Korshunova S. G., Sokolov E. N. (2008). The semantic component of the evoked potential differentiation. Spanish Journal of ...
Blenner, J. L.; Yingling, C. D. (1994). "Effects of prefrontal cortex lesions on visual evoked potential augmenting/reducing". ... The N100 is a slow-developing evoked potential. From one to four years of age, a positive evoked potential, P100, is the ... Older children start to develop a negative evoked potential at 200 ms that dominates evoked potentials until adolescence; this ... P600 Somatosensory evoked potential Visual N1 Warnke, A.; Remschmidt, H.; Hennighausen, K. (1994). "Verbal information ...
"Developing an online steady-state visual evoked potential-based brain-computer interface system using EarEEG". 2015 37th Annual ... "A Study of Evoked Potentials From Ear-EEG". IEEE Transactions on Biomedical Engineering. 60 (10): 2824-2830. doi:10.1109/TBME. ... Other potential use cases which are known to have been explored are driver drowsiness detection,[47] BCI[48][49] and biometric ... Auditory evoked responses from Ear-EEG recordings. EMBC 2012. San Diego, Cal. doi:10.1109/EMBC.2012.6345999.. ...
... and visual evoked and event-related potentials (P300)". Neuroscience Letters. 415 (2): 185-9. doi:10.1016/j.neulet.2007.01.021 ...
This form of testing utilizes EEG recordings of visual-evoked potentials through the use of electrodes. In one experiment, ... An evoked potential study". Neuropsychologia. 47 (12): 2677-81. doi:10.1016/j.neuropsychologia.2009.05.002. PMID 19442677. ... Chromostereopsis is a visual illusion whereby the impression of depth is conveyed in two-dimensional color images, usually of ... The fovea is located temporally to the optical axis and as a result, the visual axis passes through the cornea with a nasal ...
Bonmassar G; Anami K; Ives JR; Belliveau JW) (1999). "Visual evoked potential (VEP) measured by simultaneous 64-Channel EEG and ... The simultaneous acquisition of EEG and fMRI data of sufficient quality requires solutions to problems linked to potential ... Scalp EEG reflects the brain's electrical activity, and in particular post-synaptic potentials (see Inhibitory postsynaptic ... current and Excitatory postsynaptic potential) in the cerebral cortex, whereas fMRI is capable of detecting haemodynamic ...
He became best known for his work on pattern-reversal visual evoked potential. With Ian McDonald he developed a technique which ...
These brain responses can be examined using visual- and sensory-evoked potentials. While the above criteria allow for a non- ... Gronseth GS, Ashman EJ (May 2000). "Practice parameter: the usefulness of evoked potentials in identifying clinically silent ... The most commonly used diagnostic tools are neuroimaging, analysis of cerebrospinal fluid and evoked potentials. Magnetic ... His symptoms began at age 28 with a sudden transient visual loss (amaurosis fugax) after the funeral of a friend. During his ...
... such as evoked potentials in the early visual cortex, or via a modulation of coupling among neural populations; for example, ... "Electroencephalogram and visual evoked potential generation in a mathematical model of coupled cortical columns". Biological ... transforms the membrane potential into a firing rate of action potentials. DCM for LFP (Local Field Potentials). Extends DCM ... Some of the specific models used in DCM are as follows: Physiological models: Convolution models: DCM for evoked responses (DCM ...
Siegel, J., & Driscoll, P. (1996). Recent Developments in an Animal Model of Visual Evoked Potential Augmenting/Reducing and ... This paper found that there were four components to sensation seeking: thrill; social; visual; and antisocial. Form III was the ...
Gould, J.E., & Chalupa, L.M. Modifications of pulvinar and geniculo-cortical evoked potentials during visual discrimination ... "National Academy of Sciences Washington, D.C." Chalupa, L.M., & Anchel, H. Visual input to the pulvinar via lateral geniculate ... superior colliculus and visual cortex in the cat. Exp. Neurol. 36:449-262. Johnson, R., Wilson, C.L., & Edgerton, V.R. Senate. ...
Steady-state visually evoked potentials (SSVEPs) use potentials generated by exciting the retina, using visual stimuli ... It was a noninvasive EEG (actually Visual Evoked Potentials (VEP)) control of a cursor-like graphical object on a computer ... The electrodes were placed so that they pick up steady state visual evoked potentials (SSVEPs). SSVEPs are electrical responses ... sensory event-related potentials, (3) brain stem potentials, and (4) cognitive event-related potentials. The performance of the ...
Srinivasan, R., Bibi, F.A., Nunez, P.L., (2006) Steady-state visual evoked potentials: distributed local sources and wave-like ... 2006) Exploring the temporal dynamics of the spatial working memory n-back task using steady state visual evoked potentials ( ... Regan, D., (1989). Human Brain Electrophysiology: Evoked Potentials and Evoked Magnetic Fields in Science and Medicine. ... Steady state visually evoked potential topography associated with a visual vigilance task. Brain Topography 3: 337-347. ...
JOHNSTON V. S., Holcomb P. J.: Probability Learning and the P3 Component of the Visual Evoked Potential in Man. ... WANG, X. T., Johnston, V. S., and Oliver, J. C.: Evoked Brain Potential Studies of Emotional and Cognitive Processes. Acta ... in Current Trends in Event-Related Potential Research. (E.E.G. Supp. 40) Eds. R. Johnson Jr., J.W. Rohrbaugh & R.Parasuraman. ... OLIVER-RODRIGUEZ, J. C., Guan, J., and Johnston, V.S. Gender differences in Late Positive components evoked by Human Faces. ...
... stimulus evoked responses. Subspecialties include electroencephalography, electromyography, evoked potential, nerve conduction ... and visual arts) and their application to medical education and practice. ... It was under the Byzantines with physicians such of Theophilus Protospatharius that they realized the potential in uroscopy to ... and potential surgical candidates on the hospital wards. Surgery has many sub-specialties, including general surgery, ...
Gex-Fabry, M; Balant-Gorgia, AE; Balant, LP (February 1995). "Potential of concentration monitoring data for a short half-life ... "Comparison of the effects of moclobemide and selegiline on tyramine-evoked mydriasis in man". Br J Clin Pharmacol. 45 (6): 551 ... Visual disturbances. *Increased hepatic enzymes without associated clinical sequelae.. Contraindications[edit]. Avoid use in:[ ... Sieradzan K, Channon S, Ramponi C, Stern GM, Lees AJ, Youdim MB (August 1995). "The therapeutic potential of moclobemide, a ...
... , like many forms of therapy, has the potential to be a highly culturally sensitive one. Empathy in general is an ... Jones, J. D. (2005). A comparison of songwriting and lyric analysis techniques to evoke emotional change in a single session ... Multi-modal stimulation (MMS) includes the applications of auditory, tactile, vestibular, and visual stimulation that helps aid ... It's the added complexity to cultural empathy that comes from adding music that provides both the greater risk and potential to ...
... but a smile will only be evoked through touch between parent and baby. This primary form of communication is greatly delayed ... accompanied by concerted efforts to ensure the accessibility of information technology to all potential users, including the ... Central visual acuity of 20/200 or less in the better eye with corrective glasses or central visual acuity of more than 20/200 ... Visual impairments may take many forms and be of varying degrees. Visual acuity alone is not always a good predictor of the ...
Two types of gamma activity were found by Snyder & Large: induced gamma activity, and evoked gamma activity. Evoked gamma ... The hair cells in the cochlea release neurotransmitter as a result, causing action potentials down the auditory nerve. The ... A system proposed to explain this understanding of actions is that visual representations of actions are mapped onto our own ... In a follow-up study, Koelsch, Schroger, and Gunter (2002) investigated whether ERAN and N5 could be evoked preattentively in ...
If the generator potential reaches threshold, a volley of action potentials (nerve impulses) are triggered at the first node of ... Torebjörk HE, Ochoa JL (December 1980). "Specific sensations evoked by activity in single identified sensory units in man". ... Visual system (sense of vision). *Auditory system (sense of hearing). *Vestibular system (sense of balance) ... When a mechanoreceptor receives a stimulus, it begins to fire impulses or action potentials at an elevated frequency (the ...
They are called somatosensory evoked potentials when they are elicited by sensory (vs. cognitive or motor) event stimuli. The ... The first negative and positive swings (see Visual N1, C1 and P1 (neuroscience)) in response to visual stimulation are of ... Visual processing and image enhancementEdit. *Scientific visualization an interdisciplinary branch of science primarily ... Event-related potential positive and negative 10µ to 100µ Volts (µ is millionths) responses, measured via noninvasive ...
Evoked potential. *Bereitschaftspotential. *P300. *Auditory evoked potential. *Somatosensory evoked potentials. *Visual evoked ... in intensity of the evoked OAE [20]. All results were however reported only as group averages, and no attempt was made to ... transient evoked otoacoustic emission (TEOAE) and distortion product otoacoustic emission (DPOAE). In a recent US patent issued ...
Microsoft Visual Studio[edit]. The compiler suite from Microsoft implements buffer overflow protection since version 2003 ... Canaries are alternately known as cookies, which is meant to evoke the image of a "broken cookie" when the value is corrupted. ... then the bug is a potential security vulnerability that allows an attacker to inject executable code into the running program ... C and C++ compiler supports stack-smashing protection with options similar to those provided by GCC and Microsoft Visual Studio ...
Research measuring brain volume, P300 auditory evoked potentials, and intelligence shows a dissociation, such that both brain ... For instance, among modern Homo sapiens, northern populations have a 20% larger visual cortex than those in the southern ... intelligence and auditory evoked potentials". Personality and Individual Differences. 17 (3): 357-367. doi:10.1016/0191-8869(94 ... and this in turn is used as a rough indicator of the potential intelligence of the organism. Cranial capacity is often tested ...
For example, when the subject receives a visual cue. This could be the reflection of a Zener card in the holder's glasses. In ... The parapsychology experiments at Duke evoked criticism from academics and others who challenged the concepts and evidence of ... Human Potential Movement. *Hypnosis. *Large Group Awareness Training. *Lucid dreaming. *Mind control ...
Expensive copper wire was used only for selected trees that had real potential.[31][32] In the 1920s and 1930s, Toolsmith ... These three elements are chosen to complement each other and evoke a particular season, and are composed asymmetrically to ... that make them appropriate for the compact visual scope of bonsai. ...
Its visual system is attuned more to movement and/or contrast than to object details.[50][54][55] It is especially sensitive to ... The whitetip reef shark is highly responsive to olfactory, acoustic, and electrical cues given off by potential prey. ... Tiny fishes fuel life on coral reefs Coral reefs typically evoke clear, turquoise waters and a staggering number of colorful ... Porcupinefish inflate themselves by swallowing water or air, which restricts potential predators to those with bigger mouths. ...
... "evoked response potentials" eller "event-related potentials" forkortet ERP). I forbindelse med analyse af sådanne signaler har ... "Posterior α activity is not phase-reset by visual stimuli". Proc Natl Acad Sci USA. 103 (8): 2948-2952. ... efter engelsk local field potential). Sådanne målinger fortages dog normalt kun på forsøgsdyr eller patienter, der behandles ...
There may also be some visual influence on appetite. According to some research, the colour red increases appetite.[29] ... There is no neurological explanation as to why chocolate fudge cake evokes more appetite than porridge, but rats are like ... Mechanisms controlling appetite are a potential target for weight loss drugs. Appetite control mechanisms seem to strongly ...
An evoked response study of congenitally deaf kittens used local field potentials to measure cortical plasticity in the ... There are multiple auditory areas (much like the multiple areas in the visual cortex), which can be distinguished anatomically ... The field potentials measured for artificially stimulated CDC were eventually much stronger than that of a normal hearing cat.[ ... The evoked responses during the sixth and seventh omitted notes are assumed to be imagined, and were characteristically ...
Girard notes the productive potential of competition: "It is because of this unprecedented capacity to promote competition ... set in the past and which has to be evoked for the reader through predication and description. Dramatic worlds, on the other ... representation of the visual appearance of things. ...
Evoked potentials. Negativity. Bereitschaftspotential. ELAN. N100. Visual N1. N170. N200. N2pc. N400. Contingent negative ... Epstein, Charles M. (1983). Introduction to EEG and evoked potentials. J. B. Lippincott Co. ISBN 978-0-397-50598-2. .. [page ... sensory event-related potentials, (3) brain stem potentials, and (4) cognitive event-related potentials. The performance of the ... Derivatives of the EEG technique include evoked potentials (EP), which involves averaging the EEG activity time-locked to the ...
... meant to evoke the visual experience of an LSD trip. LSD had a strong influence on the Grateful Dead and the culture of " ... Cohen, S. (1959). The therapeutic potential of LSD-25. A Pharmacologic Approach to the Study of the Mind, p251-258. ... The mutagenic potential of LSD is unclear. Overall, the evidence seems to point to limited or no effect at commonly used doses. ... Changes in auditory and visual perception are also typical.[42][43]. Some sensory effects may include an experience of radiant ...
Visual cortex[edit]. The visual cortex refers to the primary visual cortex, labeled V1 or Brodmann area 17, as well as the ... This action potential then travels along afferent neurons to specific brain regions where it is processed and interpreted.[5] ... and can evoke somatic sensations through electrical stimulation. Areas 1 and 2 receive most of their input from area 3. There ... All stimuli received by the receptors listed above are transduced to an action potential, which is carried along one or more ...
Talk:Blob (visual system). *Talk:Body image (medicine). *Talk:Boundary cell. *Talk:Brain and Behavior ... Talk:Electrotonic potential. *Talk:Emboliform nucleus. *Talk:Endogenous agonist. *Talk:Endomorphin. *Talk:Endorestiform nucleus ... Talk:Evoked field. *Talk:Extended amygdala. *Talk:External capsule. *Talk:External nasal nerve ...
... which relays visual inputs from the retina to the visual cortex, have been shown to generate the BOLD signal correctly when ... The local field potential, which includes both post-neuron-synaptic activity and internal neuron processing, better predicts ... Since scaling is just multiplication by a constant number, this means an event that evokes, say, twice the neural response as ... An example of the broad range here is given by the visual processing system. What the eye sees is registered on the ...
The camouflage of a physical object often works by breaking up the visual boundary of that object. This usually involves ... Although other, less common, partner-focused motives such as using to deception to evoke jealous reactions from their partner ... other potential romantic mates).[28] Sociosexual orientation is concerned with how freely individuals partake in casual sex ... Animals for example may deceive predators or prey by visual, auditory or other means. ...
Evoked potentials and event-related potentials are obtained from an electroencephalogram by stimulus-locked averaging, i.e. ... "Dynamic brain sources of visual evoked responses". Science. 295 (5555): 690-694. Bibcode:2002Sci...295..690M. doi:10.1126/ ... events that do not form evoked potentials/evoked fields, or induced activity. Spontaneous activity is usually considered to be ... Neurons generate action potentials resulting from changes in the electric membrane potential. Neurons can generate multiple ...
Dario Gamboni, Potential Images: Ambiguity and Indeterminacy in Modern Art, p. 96, at Google Books ... The power evoked by Gauguin's work led directly to Les Demoiselles d'Avignon in 1907.[280] ... Bowness 1971, p. 4, I have a remarkable visual memory, and I remember that period, our house and a whole lot of events.. ... Thomson 1987, p. 125, Thomson notes that Gauguin was alert to the potential for self-publicity. Camille Pissarro, no admirer of ...
Further information: Visual merchandising § Scent. The sense of smell is not overlooked as a way of marketing products. The ... This link is important, because if an individual associates positive affect (elicited by pheromones[60]), with a potential mate ... Some believe that these messages have the power to alter moods, evoke distant memories, raise their spirits, and boost self- ... Most memories that pertain to odor come from the first decade of life, compared to verbal and visual memories which usually ...
The evoked potentials and hemodynamic activity measured during encoding were found to exhibit reliable differences between ... The 1960s also saw a development in the study of visual imagery and how it is recalled. This research was led by Allan Paivio, ... The word presentation can either be visual or auditory. There are two basic experimental methods used to conduct cued recall, ... Rugg MD, Allan K (2000) Event-related potential studies of memory. In: The oxford handbook of memory (Tulving E, Craik FIM, eds ...
The visual discrimination test has two components. In the first component, "reversal learning", participants are presented with ... In contrast to resting state and decision related activity, cues associated with drugs evoke robust OFC activity that ... The lateral OFC has been proposed to reflect potential choice value, enabling fictive(counterfactual) prediction errors to ... The evidence for responses to visual, gustatory, somatosensory, and olfactory stimuli is robust, but evidence or auditory ...
Abbas A, Roth BL (December 2008). "Pimavanserin tartrate: a 5-HT2A inverse agonist with potential for treating various ... on certain areas such as the visual cortex and the orbitofrontal cortex.[7] This receptor was first noted for its importance as ... "Stress blunts serotonin- and hypocretin-evoked EPSCs in prefrontal cortex: role of corticosterone-mediated apical dendritic ... Recent research has suggested potential signaling differences within the somatosensory cortex between 5-HT2A agonists that ...
Background In order to assess the influence of optical factors on the multifocal visual evoked potential (mfVEP), we obtained ... Berman MS, Seki S (1982) Blur-induced changes in the visual evoked potential. Am J Optom Physiol Opt 59:556-560PubMedGoogle ... In order to assess the influence of optical factors on the multifocal visual evoked potential (mfVEP), we obtained mfVEPs with ... Klistorner AI, Graham SL (2001) Electroencephalogram-based scaling of multifocal visual evoked potentials: effect on ...
... can provide important diagnostic information regarding the functional integrity of the visual system. This document updates the ... Visual evoked potential Pattern-reversal visual evoked potential Pattern onset/offset Visual evoked potential Flash visual ... Visual evoked potentials (VEPs) can provide important diagnostic information regarding the functional integrity of the visual ... Odom JV, Bach M, Brigell M, Holder GE, McCulloch DL, Tormene AP (2010) ISCEV standard for clinical visual evoked potentials ( ...
Visual evoked potentials in rotogravure printers exposed to toluene. Informaci n bibliogr fica. Dec. 1990, Vol.47, No.12, p.819 ... Visual evoked potentials (VEPs) from stimulation by checkerboard pattern reversal were examined in 54 rotogravure printers ...
visual evoked potential. Whats Known on This Subject:. Impaired visual development has been reported in infants born to ... 12 Flash visual evoked potentials (VEPs) in infancy reflect the integrity and maturity of the visual system,13-16 and we have ... Neonatal Visual Evoked Potentials in Infants Born to Mothers Prescribed Methadone. Laura McGlone, Ruth Hamilton, Daphne L. ... Visual evoked potential in the newborn: does it have predictive value? Semin Fetal Neonatal Med. 2006;11(6):459-463pmid: ...
The waveform of the evoked visual potential is color specific. This specificity is absent in a color-deficient observer. ...
... or evoked responses, measure the electrophysiologic responses of the nervous system to a variety of stimuli. In theory, almost ... Visual Evoked Potential. The visual evoked potential (VEP) tests the function of the visual pathway from the retina to the ... evoked potential (EP) studies-including visual evoked potential (VEP), brainstem auditory evoked potential (BAEP), and ... Comparisons of SEP, visual evoked potential (VEP), and brainstem auditory evoked potential (BAEP) have found that VEP testing ...
Evoked Potentials, Visual: The electric response evoked in the cerebral cortex by visual stimulation or stimulation of the ...
Learn more about Visual Evoked Potential Test at Medical City Dallas DefinitionReasons for TestPossible ComplicationsWhat to ... A visual evoked potential test (VEP) is used to look for problems in the brain or nerves that affect vision. A machine records ... webvision.med.utah.edu/book/electrophysiology/visually-evoked-potentials. Updated July 14, 2015. Accessed May 16, 2016. ... www.nationalmssociety.org/Symptoms-Diagnosis/Diagnosing-Tools/Evoked-Potentials. Accessed May 16, 2016. ...
This study presents a method for accomplishing this by smoothly modulating the luminance of a visual stimulus using a ... Faster and less obtrusive means for measuring a Visual Evoked Potential would be valuable in clinical testing and basic ... The VESPA: a method for the rapid estimation of a visual evoked potential Neuroimage. 2006 Oct 1;32(4):1549-61. doi: 10.1016/j. ... Faster and less obtrusive means for measuring a Visual Evoked Potential would be valuable in clinical testing and basic ...
Visual evoked potentials of Niemann-Pick type C1 mice reveal an impairment of the visual pathway that is rescued by 2- ... Visual evoked potentials of Niemann-Pick type C1 mice reveal an impairment of the visual pathway that is rescued by 2- ... Visual evoked potentials of Niemann-Pick type C1 mice reveal an impairment of the visual pathway that is rescued by 2- ... Visual evoked potentials of Niemann-Pick type C1 mice reveal an impairment of the visual pathway that is rescued by 2- ...
Visual evoked potentials is an important visual electrophysiological tool which has been used for the evaluation of visual ... glaucomatous damage evidenced by reduction in MD could depend on the delay in neural conduction from retina to the visual ... correlations between the magnitude of the VEP parameters and MD of Humphrey static perimetry suggest that the impaired visual ... Advent of Multifocal Visual Evoked Potentials. With the multifocal technique, visual evoked potentials (VEPs) can be recorded ...
... through evoked potential testing. Although the technique to acquire visual evoked potentials using flashes of diffuse light ... Figure 1 Flash-visual evoked potential (F-VEP) of a subject of research showing the robust N2 peak at 86ms latency. ... Longitudinal stability of visual evoked potentials in children and adolescents with hydrocephalus. Dev Med Child Neurol. 2001; ... Andersson L, Sjölund J, Nilsson J. Flash visual evoked potentials are unreliable as markers of ICP due to high variability in ...
Multifocal visual evoked potential (mfVEP) data. Interpolated visual fields: estimated visual loss in decibels in 60 mfVEP ... psychophysical visual‐field data and physiological visual evoked potential data. In any case, when interpolated visual fields ... Hood D C, Greenstein V C, Odel J G. et al Visual field defects and multifocal visual evoked potentials. Evidence of a linear ... Objective measurements of visual function would be ideal, and multifocal visual evoked potential (mfVEP) recording may be able ...
Visual assessment (visual field, visual acuity, pattern visual evoked potential) are realised before and after surgery. ... Advantage of Using Intraoperative Visual Evoked Potentials to Preserve Visual Function During Surgical Procedures Near the ... Advantage of Using Intraoperative Visual Evoked Potentials to Preserve Visual Function During Surgical Procedures Near the ... on the visual prognosis at six months after surgery The visual assessment consisting of a visual field, a visual acuity, and ...
The third visual evoked potential, 60 minutes after drug ingestion.. Visual evoked potential (P300) A sound-attenuated room was ... visual evoked potential; 2) Administration of capsule (bromazepam or placebo); 3) The second visual evoked potential, 20 ... Analysis of the influence of bromazepam on cognitive performance through the visual evoked potential (P300) ... The evoked potential (EP) or event-related potential (ERP) has provided the means to examine the on-line processing of ...
The visual evoked potentials in the investigation of diseases of the optic nerve. In: Halliday AM, editor. Evoked potentials in ... Pattern-shift visual evoked potentials: interpretation. In: Chiappa KH, editor. Evoked potential in clinical medicine. 3rd ed. ... Studies of human visual pathophysiology with visual evoked potentials. Clin Neurophysiol. 2006;117:1414-33. PubMedCrossRef ... The asymmetrical visual evoked potential to pattern reversal in one half field and its significance for the analysis of visual ...
Visually-evoked 3-5 Hz membrane potential oscillations reduce the responsiveness of visual cortex neurons in awake behaving ... Visually-evoked 3-5 Hz membrane potential oscillations reduce the responsiveness of visual cortex neurons in awake behaving ... Visually-evoked 3-5 Hz membrane potential oscillations reduce the responsiveness of visual cortex neurons in awake behaving ... Visually-evoked 3-5 Hz membrane potential oscillations reduce the responsiveness of visual cortex neurons in awake behaving ...
... ... The IAF also predicts (ii) the amplitude of the visual evoked potential (VEP), as well as (iii) the amplitude of the alpha- ... The relation between IAF, alpha-amplitude, evoked potential and vascular response is discussed in the framework of a simple ... Most importantly, (iv) IAF correlates with the oxygenation response to visual stimulation: A high IAF predicts a low alpha- ...
Through event-related potentials (ERPs), the present study examined the effect of postural control demands (PDs) on AIS central ... Through event-related potentials (ERPs), the present study examined the effect of postural control demands (PDs) on AIS central ... Subjective visual vertical (SVV) judgment and standing stability were separately investigated among patients with adolescent ... Subjective visual vertical (SVV) judgment and standing stability were separately investigated among patients with adolescent ...
... Prem Parkash Gupta, Sushma Sood,1 ... with no clinical evidence of visual impairment or peripheral neuropathy have visual evoked potentials (VEP) abnormalities on ... Visual evoked potential in young adults: A normative study. Indian J Physiol Pharmacol. 1989;33:247-9. [PubMed] ... Visual evoked potentials in clinical neurology. In: Aminoff MJ, editor. Electrodiagnosis in Clinical Neurology. USA: Churchill ...
Effects of isoflurane on the visual evoked potentials in rats Nitin Chitranshi; Yuyi You; Vivek Kumar Gupta; Alexander ... Effects of isoflurane on the visual evoked potentials in rats You will receive an email whenever this article is corrected, ... However, it can potentially affect visual evoked potential (VEP) recordings due to GABAergic activity associated with it and ... Effects of isoflurane on the visual evoked potentials in rats. Invest. Ophthalmol. Vis. Sci. 2015;56(7 ):468. ...
Visual evoked potentials (VEPs) are an objective means of measuring the function of the visual pathway and are understood to be ... Visual Neuroscience , May 2010. Interrelationship of Optical Coherence Tomography and Multifocal Visual-Evoked Potentials after ... amplitude of multifocal visual evoked potentials [mfVEPs]) measures of the integrity of the visual pathway in the postacute ... Multifocal topographic visual evoked potential: improving objective detection of local visual field defects. Invest Ophthalmol ...
... as well as other pathways which are involved in visual attention. ... in most test parameters suggest that OVR affects the visual ... visual-evoked potential amplitude; visual-evoked potential latency. ... Effect of oculomotor vision rehabilitation on the visual-evoked potential and visual attention in mild traumatic brain injury ... on the visual-evoked potential (VEP) and visual attention in the mTBI population. ...
Mackay, Alison (2003) Assessing childrens visual acuity with steady state evoked potentials. PhD thesis, University of Glasgow ... Objective acuity assessment by Visual Evoked Potential (VEP) provides a complementary assessment in those subjects who cannot ... The aim of this study was to develop and evaluate a rapid, objective visual acuity assessment. The technique was named the step ... The majority of children attending ophthalmology clinics require a visual acuity assessment. The optimal technique depends on ...
Visual evoked potentials in parkinsonism and dopamine blockade reveal a stimulus-dependent dopamine function in humans. ... Visual evoked potentials in parkinsonism and dopamine blockade reveal a stimulus-dependent dopamine function in humans. ... The detection of VEP abnormalities in Parkinsons disease was dependent on the spatial frequency of the visual stimulus (a ... depending on the spatial frequency of the visual stimulus. These findings suggest that the dopaminergic mechanism involved in ...
mean P100 visual-evoked potentials latencies. RD. radial diffusivity. VEP. visual-evoked potentials. ... Pattern reversal visual evoked potentials as a measure of visual pathway pathology in multiple sclerosis. Mult Scler 2003;9:529 ... P100 visual-evoked potentials and fractional anisotropy and significant positive correlations between mean P100 visual-evoked ... 10 Evoked potentials, in general, and combined evoked potential analysis, in particular, seem to correlate well with the long- ...
Quantitative Fiber Tracking of the Optic Radiation Is Correlated with Visual-Evoked Potential Amplitude in Preterm Infants. H.C ... Quantitative Fiber Tracking of the Optic Radiation Is Correlated with Visual-Evoked Potential Amplitude in Preterm Infants ... Quantitative Fiber Tracking of the Optic Radiation Is Correlated with Visual-Evoked Potential Amplitude in Preterm Infants ... Quantitative Fiber Tracking of the Optic Radiation Is Correlated with Visual-Evoked Potential Amplitude in Preterm Infants ...
... ... Two such tests that have been useful for this purpose are Dynamic Visual Acuity (DVA) and Vestibular Evoked Myogenic Potentials ...
Aim To investigate optic nerve function using the pattern-reversed visual evoked cortical potentials (VECP) before and after ... Course of pattern-reversed visual evoked cortical potentials in 30 eyes after bony orbital decompression in dysthyroid optic ... Course of pattern-reversed visual evoked cortical potentials in 30 eyes after bony orbital decompression in dysthyroid optic ... We examined visual acuity (VA), VECP P100 amplitudes and latencies, as well as proptosis using Hertels exophthalmometry. ...
Title:Symmetry-Correlated Component in the Visual-Evoked Potential: Electrophysiological Study of Visual Symmetry Perception in ... Symmetry-Correlated Component in the Visual-Evoked Potential: Electrophysiological Study of Visual Symmetry Perception in ... visual-evoked potential.. Abstract:Humans are able to perceive symmetry information in the visual environment rapidly and ... "Symmetry-Correlated Component in the Visual-Evoked Potential: Electrophysiological Study of Visual Symmetry Perception in ...
  • Visual evoked potentials (VEPs) can provide important diagnostic information regarding the functional integrity of the visual system. (springer.com)
  • Visual evoked potentials (VEPs) from stimulation by checkerboard pattern reversal were examined in 54 rotogravure printers exposed to toluene (all men, aged 22-64 years, duration of exposure 1-41 years). (ilo.org)
  • Pilot data showed abnormal flash visual evoked potentials (VEPs) in neonates exposed to methadone in utero, but results were confounded by intrauterine growth restriction, gestation, and ongoing drug misuse. (aappublications.org)
  • In utero exposure to prescribed substitute methadone is associated with altered flash VEPs in the newborn period and these infants may warrant early clinical visual assessment. (aappublications.org)
  • 7 - 12 Flash visual evoked potentials (VEPs) in infancy reflect the integrity and maturity of the visual system, 13 - 16 and we have demonstrated abnormal VEPs in newborn infants exposed to methadone in utero. (aappublications.org)
  • Abnormal infant flash VEPs in other high-risk neonatal groups have been linked with long-term visual, motor, and learning disabilities. (aappublications.org)
  • 13 - 15 The aims of the current study were to investigate the effects of maternal drug misuse on neonatal flash VEPs and to assess any relationship between early visual electrophysiology and subsequent neonatal abstinence syndrome (NAS). (aappublications.org)
  • We have addressed this issue by characterizing the visual evoked potential (VEP) response of Npc1 (-/-) mice and determining if/how HPßCD administration influences the VEPs of both Npc1 (-/-) and Npc1 (+/+) mice. (nih.gov)
  • Included are the previous works related to the clinical utilization of VEPs for the objective assessment of typical visual field defects of POAG. (hindawi.com)
  • This study aimed to investigate human visual-evoked potentials (VEPs) in response to complex object images of varying symmetry, and to find their neural correlates. (eurekaselect.com)
  • The visual evoked potential (VEP) can be used to assess the integrity and maturity of the infant visual pathway and both visual and neurodevelopmental abnormalities can be predicted by abnormal VEPs in infancy. (gla.ac.uk)
  • The same cohort of drug-exposed and comparison infants was invited for clinical visual evaluation at six months of age in conjunction with pattern-onset VEPs and Griffiths developmental assessment. (gla.ac.uk)
  • The present study searched for evidence supporting this hypothesis by comparing the visual evoked potentials (VEPs) elicited by striped patterns of specific spatial frequencies (0.5, 3, and 13 cycles-per-degree) between a group of 29 migraineurs (17 with aura/12 without) and 31 non-migraineurs. (lancs.ac.uk)
  • Pattern reversal visual evoked potentials (PR-VEPs) have been recorded in 50 patients with minor head injury (MHI) on days 1 and 30 after trauma and the data compared to 20 normals. (elsevier.com)
  • The aim was to investigate a possible visual pathway affection in MHI and test the usefulness of PR-VEPs as an objective noninvasive tool in the detection of a possible subclinical affection of the visual system in MHI. (elsevier.com)
  • Visual Evoked Potentials (VEPs) evaluate the visual nervous system from the eyes to the occipital (visual) cortex of the brain. (capitalhealth.org)
  • We investigated a means to measure visual acuity in awake mice using visually evoked potentials (VEPs). (csp.edu)
  • Using stereotaxic implanted electrodes in the animal's primary visual cortex, the evoked VEPs were recorded and analyzed. (csp.edu)
  • However, at higher spatial frequencies, a reversal occurs where horizontal gratings evoked larger VEPs. (csp.edu)
  • These data suggest vertical and horizontal stimuli have different effects on generating VEPs although further investigation is required to determine which stimulus is most suitable for measuring visual acuity in mice. (csp.edu)
  • Measuring Visual Acuity in Awake Mice Using Visually Evoked Potentials (VEPs) (Thesis, Concordia University, St. Paul). (csp.edu)
  • The use of VEPs and ERGs has been demonstrated to aid in the diagnosis and treatment of a variety of visual disorders. (coopereyecare.com)
  • Between attacks, migraineurs lack habituation in standard visual evoked potentials (VEPs). (wiley.com)
  • Visual evoked potentials (VEPs) were recorded from a total of 97 1- to 10-day-old infants, with phase-reversing sinusoidal grating stimuli. (ox.ac.uk)
  • Visual evoked potentials (VEPs) provide the tools to examine the functional integrity of these areas and may provide useful indicators of early disease progression. (bris.ac.uk)
  • OBJECTIVE: To assess the functional integrity of visual association area processing in AD and amnestic mild cognitive impairment (aMCI) using VEPs. (bris.ac.uk)
  • Up until the present, it has been difficult to demonstrate Uhthoffs phenomenon by visually evoked potentials (VEPs). (elsevier.com)
  • Her right visual acuity was 0.02 and improvement of subjective visual acuity, and temporal frequency characteristics of the VEPs were seen after ingestion of cold water. (elsevier.com)
  • The purpose of our study was to investigate the effects of stress and sulfite on visual evoked potentials (VEPs) and to examine the relationship between lipid peroxidation and VEP changes. (ktu.edu.tr)
  • The aim of this study was to evaluate longitudinally functional and neuro-radiologic findings in childhood optic gliomas (OG), by comparing flicker visual evoked potentials (F-VEPs) with brain magnetic resonance imaging (MRI) changes. (elsevier.com)
  • Somatosensory Evoked Potentials (SSEPs) assess pathways from nerves in the arms or legs, through the spinal cord to the brainstem or cerebral cortex. (capitalhealth.org)
  • What is the role of somatosensory evoked potentials (SEPs) in determining the prognosis of postanoxic coma? (medscape.com)
  • visual evoked potentials, and somatosensory evoked potentials , which are elicited by electrical stimulation of peripheral nerve. (wikipedia.org)
  • Somatosensory evoked response (SSER) test. (nhrmc.org)
  • May include visual, auditory, or somatosensory evoked potentials. (wikipedia.org)
  • Visually evoked potentials. (medicalcityhospital.com)
  • Available at: http://webvision.med.utah.edu/book/electrophysiology/visually-evoked-potentials. (medicalcityhospital.com)
  • Ever since visually evoked cortical potentials were first used as a diagnostic aid the important question has been whether they could detect visual field defects. (hindawi.com)
  • By performing 2-photon guided whole-cell recordings from layer 2/3 excitatory and inhibitory neurons in the visual cortex of awake behaving animals, we found visually-evoked stereotyped 3-5 Hz Vm oscillations that disrupt excitatory responsiveness to visual stimuli. (jneurosci.org)
  • Advanced and introductory experiments designed to teach students about central and peripheral nerve function, brain activity using non-invasive approaches (EEG and visually evoked potentials), and intracellular and extracellular action potentials. (adinstruments.com)
  • In neurology and neuroscience research, steady state visually evoked potentials (SSVEP) are signals that are natural responses to visual stimulation at specific frequencies. (wikipedia.org)
  • Evoked potentials (EPs), or evoked responses, measure the electrophysiologic responses of the nervous system to a variety of stimuli. (medscape.com)
  • Despite this disruption to sensory processing, visual cues were critical for evoking 3-5 Hz Vm oscillations when animals performed discrimination tasks and passively viewed drifting grating stimuli. (jneurosci.org)
  • VEP are electrical potential differences generated in response to visual stimuli and are usually recorded over vortex. (pubmedcentralcanada.ca)
  • Retinal inhomogeneities across the visual field can introduce color shifts and luminance artifacts to uniform, large-field stimuli. (arvojournals.org)
  • We created large-field stimuli equated across the visual field for luminance and hue shifts using psychophysical methods. (arvojournals.org)
  • If you have any medical conditions such as epilepsy , the visual stimuli you are exposed to is unlikely to set off seizure activity. (myvmc.com)
  • Sensory evoked potentials studies involve 3 tests that measure response to visual, auditory, and electrical stimuli. (nhrmc.org)
  • At the lowest spatial frequency, vertical stimuli evoked the largest VEP amplitude. (csp.edu)
  • Visual stimuli also evoke high-frequency oscillations in the gamma band range (GBOs, 20-35 Hz) assumed to be generated both at subcortical (early GBOs) and cortical levels (late GBOs). (wiley.com)
  • This study evaluates the hypothesis that overlapping stimuli can evoke changes in SSVEP activity sufficient to control a BCI. (neurotechcenter.org)
  • They examine the effects of nerve stimulation and other stimuli on skin potential, investigate heart rate variability with normal and deep breathing, and observe the physiological effects of the Valsalva maneuver and of rapid postural change. (adinstruments.com)
  • In this lab, learners record compound action potentials (CAPs) from a cockroach leg nerve in response to various physical stimuli. (adinstruments.com)
  • In order to assess the influence of optical factors on the multifocal visual evoked potential (mfVEP), we obtained mfVEPs with optimal refraction and compared them to recordings with various degrees of dioptrical defocus. (springer.com)
  • Objective measurements of visual function would be ideal, and multifocal visual evoked potential (mfVEP) recording may be able to suit this need. (pubmedcentralcanada.ca)
  • Multifocal visual evoked potential (mfVEP) data. (pubmedcentralcanada.ca)
  • abstract = "Background: Multifocal visual evoked potential (MF-VEP) assesses a wider visual field than full-field VEP (FF-VEP) and potentially offers a more precise analysis of optic nerve injury and repair following optic neuritis. (elsevier.com)
  • In a simultaneous electroencephalography (EEG) and near-infrared spectroscopy (NIRS) study, the predictive value of the individual alpha-frequency at rest (IAF) for the amplitude of neuronal and vascular responses to visual stimulation was investigated. (ovid.com)
  • An evoked potential or evoked response is an electrical potential recorded from the nervous system of a human or other animal following presentation of a stimulus , as distinct from spontaneous potentials as detected by electroencephalography (EEG), electromyography (EMG), or other electrophysiologic recording method. (wikipedia.org)
  • The purpose of this review is to describe the existing studies of electroencephalography (EEG) and evoked potentials (EPs) in Rett syndrome and discuss the open questions that must be addressed before the field can adopt these measures as surrogate endpoints in clinical trials. (frontiersin.org)
  • The American Board of Clinical Neurophysiology certifies in electroencephalography (EEG), Evoked Potentials (EP), Polysomnography (PSG), Epilepsy Monitoring, and Neurologic Intraoperative Monitoring (NIOM). (wikipedia.org)
  • Although the technique to acquire visual evoked potentials using flashes of diffuse light exhibits more variability compared to techniques that apply pattern-reversal stimulation, it offers the advantage that it may be performed in the supine position and does not require strict cooperation and visual fixation, allowing this procedure to be performed even in comatose patients 11 , 12 . (scielo.br)
  • These parameters are special devices used for transpalpebral stimulation, complete intravenous anaesthesia without halogen or nitrous oxide, and pertinent analysis criteria of visual evoked potential (VEP). (clinicaltrials.gov)
  • To answer these questions, we performed two-photon guided whole-cell Vm recordings from primary visual cortex layer 2/3 excitatory and inhibitory neurons in awake mice during passive visual stimulation and performance of visual and auditory discrimination tasks. (jneurosci.org)
  • The IAF also predicts (ii) the amplitude of the visual evoked potential (VEP), as well as (iii) the amplitude of the alpha-rhythm during stimulation. (ovid.com)
  • Most importantly, (iv) IAF correlates with the oxygenation response to visual stimulation: A high IAF predicts a low alpha-amplitude at rest, a small VEP amplitude and a small oxygenation response. (ovid.com)
  • The Evoked Potential (EP) is a recording of electrical activity from the brain, spinal nerves, or sensory receptors in response to specific external stimulation, whether it be visual, auditory, or sensory stimulation. (capitalhealth.org)
  • [ 40 ] Repetitive stimulation demonstrates a compound muscle action potential decrement in myasthenia gravis, and an increment in Lambert-Eaton syndrome. (medscape.com)
  • Usually the term "evoked potential" is reserved for responses involving either recording from, or stimulation of, central nervous system structures. (wikipedia.org)
  • By analogy with the steady-state response of a resonant circuit that follows the initial transient response he defined an idealized steady-state evoked potential (SSEP) as a form of response to repetitive sensory stimulation in which the constituent frequency components of the response remain constant with time in both amplitude and phase. (wikipedia.org)
  • Sensory evoked potentials studies measure electrical activity in the brain in response to stimulation of sight, sound, or touch. (nhrmc.org)
  • These results show that the acupuncture stimulation contributes to the P100 latencies of pattern reversal (PR)-VEP to some subjects who have delayed latencies, and this electrophysiological method is a valuable technique in monitoring the effectiveness of acupuncture therapy in the improvements of visual functions. (elsevier.com)
  • Stimulation via a subretinally placed prosthetic elicits central activity and induces a trophic effect on visual responses. (nih.gov)
  • 2 , 3 ] Impairment of brainstem auditory evoked potentials in stable COPD patents has also been described. (pubmedcentralcanada.ca)
  • Long and Allen [3] reported the abnormal brainstem auditory evoked potentials (BAEP) in an alcoholic woman who recovered from acquired central hypoventilation syndrome . (wikipedia.org)
  • Katsumi O, Hirose T, Sakaue H, Mehta M, Rosenstein RB (1990) Effect of optical defocus on the steady state pattern reversal visual-evoked response. (springer.com)
  • Yukagawa E, Urano T, Nakahara M. Pattern-reversal Visual Evoked Potentials in Patients with Human T-lymphotropic Virus Type 1 Uveitis. (medscape.com)
  • Pattern-reversal visual evoked potential (PVEP) testing is an objective means of evaluating impulse conduction along the central nervous pathways. (aston.ac.uk)
  • The aim of this study was to firstly observe the possible association between glycated haemoglobin levels and P100 peak time of pattern-reversal visual evoked potentials (PVEPs) in DM. (aston.ac.uk)
  • Understanding cross-modal plasticity in the context of auditory deprivation, and the potential for reversal of these changes following intervention, may be vital in directing intervention and rehabilitation options for clinical populations with hearing loss. (mdpi.com)
  • abstract = "Visual evoked potential (VEP) testing is used frequently and is an important ophthalmologic physiological test to examine visual functions objectively. (elsevier.com)
  • abstract = "BACKGROUND: Cortical visual association areas are highly vulnerable to Alzheimer's disease (AD) microscopic pathology. (bris.ac.uk)
  • The visual evoked potential (VEP) tests the function of the visual pathway from the retina to the occipital cortex. (medscape.com)
  • It measures the conduction of the visual pathways from the optic nerve, optic chiasm, and optic radiations to the occipital cortex. (medscape.com)
  • Morphological and functional anomalies of Npc1 (-/-) mouse retina have also been observed, although the functional integrity of the visual pathway from retina to visual cortex is still unsettled. (nih.gov)
  • VEP elicited by a brief visual stimulus were recorded from the scalp overlying the visual cortex of adult (PN, postnatal days 60, 75, 85 and 100) Npc1 (+/+) and Npc1 (-/-) mice that had received repeated injections of either HPßCD or plain vehicle. (nih.gov)
  • We have found that the transmission of visual signals from retina to visual cortex is negatively influenced by the loss of Npc1 function. (nih.gov)
  • HPßCD administration fully rescued this defect and counteracted the cholesterol accumulation in retinal ganglion cells and dorsal lateral geniculate nucleus neurons, as well as the myelin loss in optic nerve fibers and axons projecting to the visual cortex observed in of Npc1 (-/-) mice. (nih.gov)
  • In addition, the severity of global glaucomatous damage evidenced by reduction in MD could depend on the delay in neural conduction from retina to the visual cortex as revealed by the significant correlation between VEP latencies and MD which also supports the validity of the VEP testing in progression of glaucoma. (hindawi.com)
  • The visual evoked potential is the objective measurement of visual function monitored at the level of the occipital cortex with scalp electrodes. (hindawi.com)
  • 5 ] VEP provide a qualitative and quantitative measure of the optical pathway, as they indicate the functional aspects of the optic nerve, optic chiasm and tracts, lateral geniculate bodies and geniculocalcarine projection to visual cortex. (pubmedcentralcanada.ca)
  • Previous research has suggested that these unusual visual symptoms to be linked with the hyperactivity on the visual cortex of migraine sufferers. (lancs.ac.uk)
  • The electrodes for recording the ERG and VEP were implanted chronically in the sclera of the eye and on the surface of the visual cortex, respectively. (semanticscholar.org)
  • We have used single-pulse TMS with simultaneous EEG to target seven brain regions, six of which belong to the visual system [left and right primary visual area V1, motion-sensitive human middle temporal cortex, and a ventral temporal region], as determined with functional MRI-guided neuronavigation, and a vertex \'control\' site to measure the network effects of the TMS pulse. (ant-neuro.com)
  • We found the TMS-evoked potential (TMS-EP) over visual cortex consists mostly of site-dependent theta- and alphaband oscillations. (ant-neuro.com)
  • Together these results suggest that a TMS pulse applied to the visual cortex has a complex effect on brain function, engaging multiple brain networks functionally connected to the visual system with both invariant and site-specific spatiotemporal dynamics. (ant-neuro.com)
  • EEG recordings over occipital and parietal cortex were taken during the visual recognition tasks. (arvojournals.org)
  • It appears that intranasal OXT is projecting effects of emotional visual processing onto visual parietal and occipital cortex. (arvojournals.org)
  • These responses usually originate from the occipital cortex , the area of the brain involved in receiving and interpreting visual signals. (myvmc.com)
  • The VEP measures the time that it takes for a visual stimulus to travel from the eye to the occipital cortex. (myvmc.com)
  • The tests assess visual functions along the visual pathway from the retina to the primary visual cortex. (upmc.com)
  • Generators of visual evoked potentials investigated by dipole tracing in the human occipital cortex. (medscape.com)
  • This cutting-edge testing helps to measure the brain's response from a visual context to the primary visual cortex. (trinityeyecare.com)
  • This test can help to identify issues that are associated with problems in the optical nerve and the primary visual cortex. (trinityeyecare.com)
  • The electrode that measures the actual response is placed directly over the primary visual cortex, located toward the back of the head. (trinityeyecare.com)
  • The test is then conducted by creating a visual stimulus that is designed to evoke a response from the primary visual cortex. (trinityeyecare.com)
  • Many studies suggest that there is significant variability that can occur between patients due to the thickness in skulls, the morphology or shape of the visual cortex, and the specific placement of the electrodes. (trinityeyecare.com)
  • There are a few different types of VEP tests used that each stimulates the visual cortex. (trinityeyecare.com)
  • Evaluation of the Visual Cortex in advance of surgery. (trinityeyecare.com)
  • ing the visual cortex and how long it takes to get there. (coopereyecare.com)
  • Electrodes are attached to the scalp in various areas, corresponding to the lobes of the brain, to pick up the electrical potentials from the cortex of the brain. (news-medical.net)
  • Two sets of mfVEP records per subject were obtained, one with best-corrected visual acuity and another when the stimulus was defocused by +1.0, +2.0 or +3.0 D. A signal-to-noise ratio (SNR) measure was calculated for every response from the two channels. (springer.com)
  • Bach M (1996) The Freiburg visual acuity test-automatic measurement of visual acuity. (springer.com)
  • 1 - 6 There is increasing evidence to suggest that maternal drug misuse in pregnancy has adverse effects on infant visual development, with reported abnormalities, including reduced visual acuity, nystagmus, delayed visual maturation, strabismus, and refractive errors. (aappublications.org)
  • Visual morbidity (visual acuity and/or visual field deficit) must be taken into account during neurosurgical procedures for lesions near the optical pathways. (clinicaltrials.gov)
  • In this study, we assess the predictive value of relevant intraoperative variations of VEP (more than 50% variation of latency and amplitude) on the visual prognosis at six months after surgery The visual assessment consisting of a visual field, a visual acuity, and the performance of pattern transient VEP, will be performed by an ophthalmologist before surgery, and at three and six months after surgery. (clinicaltrials.gov)
  • Visual assessment (visual field, visual acuity, pattern visual evoked potential) are realised before and after surgery. (clinicaltrials.gov)
  • Visual function : visual field and visual acuity six months after surgery. (clinicaltrials.gov)
  • The majority of children attending ophthalmology clinics require a visual acuity assessment. (gla.ac.uk)
  • Objective acuity assessment by Visual Evoked Potential (VEP) provides a complementary assessment in those subjects who cannot complete subjective tests. (gla.ac.uk)
  • The aim of this study was to develop and evaluate a rapid, objective visual acuity assessment. (gla.ac.uk)
  • I-D Laplacian analysis of three occipital electrodes was significantly faster than conventional recording and analysis (Oz-Fz) at detecting ssVEP responses near visual acuity threshold (3' checks) from three years upwards, and at detecting responses to 6' and 9' checks in the 7-9 year age group. (gla.ac.uk)
  • Two such tests that have been useful for this purpose are Dynamic Visual Acuity (DVA) and Vestibular Evoked Myogenic Potentials (VEMP). (ku.edu)
  • We examined visual acuity (VA), VECP P100 amplitudes and latencies, as well as proptosis using Hertel's exophthalmometry. (bmj.com)
  • A further pilot study described longer term visual outcomes, which included nystagmus, reduced visual acuity and strabismus, in a selected group of infants and children exposed to methadone in utero, thus informing clinical and electrophysiological assessment at six months of age. (gla.ac.uk)
  • Methods: This is a four years clinical trial that included patients presenting with first attack of optic neuritis older than 16 years with visual acuity of less than 6/60 and presentation within first week of illness. (ajol.info)
  • Teller Acuity Cards are used to determine pediatric visual acuity. (upmc.com)
  • Our recent research indicates that koniocellular pathways form a subcortical site for low-acuity analysis of complex features of the visual world. (edu.au)
  • The Sweep Visual Evoked Potential (SVEP) test is used to measure visual acuity, that is, vision for detail and patterns. (childrenshospital.org)
  • In adults, visual acuity is measured with lines of letters. (childrenshospital.org)
  • The SVEP acuity test is, perhaps, most helpful in those youngsters for whom behavioral measures (Preferential Looking) give ambiguous or incomplete information about visual acuity. (childrenshospital.org)
  • Reversed Uhthoffs phenomenon is a temporal improvement of visual acuity initiated by body cooling in subjects with demyelinating optic neuropathy. (elsevier.com)
  • His right visual acuity was 0.4 and the visual acuity improved to 0.8 with ingestion of cold water. (elsevier.com)
  • On examination, Mary's right eye and orbit appeared normal, but her visual acuity was 6/6 in the left eye and 6/12 in the right eye. (mja.com.au)
  • Pale, washed-out vision with relatively little loss of visual acuity is characteristic of processes involving the optic nerve and chiasm. (mja.com.au)
  • In the Journal of Child Neurology's inaugural podcast, resident and fellow Alison Christy, MD, PhD, has a conversation with author Kandice Varcin, PhD, about her article "Visual Evoked Potentials as a Readout of Cortical Function in Infants With Tuberous Sclerosis Complex," in the February 2016 issue of the Journal of Child Neurology . (libsynpro.com)
  • Klistorner AI, Graham SL (2001) Electroencephalogram-based scaling of multifocal visual evoked potentials: effect on intersubject amplitude variability. (springer.com)
  • To evaluate the effects of unilateral compressive optic neuropathy on amplitude and latency of multifocal visual evoked potentials (mfVEPs). (pubmedcentralcanada.ca)
  • The change in the mfVEP amplitude agreed with visual field findings with regard to topography and severity of deviation from normal. (pubmedcentralcanada.ca)
  • The relation between IAF, alpha-amplitude, evoked potential and vascular response is discussed in the framework of a simple heuristic model. (ovid.com)
  • In the present study, the interrelationship was examined between structural (retinal nerve fiber layer [RNFL] thickness) and functional (amplitude of multifocal visual evoked potentials [mfVEPs]) measures of the integrity of the visual pathway in the postacute stage of ON, to determine whether there was any evidence of ongoing neural reorganization. (arvojournals.org)
  • To resolve these low-amplitude potentials against the background of ongoing EEG, ECG, EMG, and other biological signals and ambient noise, signal averaging is usually required. (wikipedia.org)
  • [7] Since a SSEP can be completely described in terms of the amplitude and phase of each frequency component it can be quantified more unequivocally than an averaged transient evoked potential. (wikipedia.org)
  • The increased amplitude of early GBOs could be related to the increased interictal visual discomfort reported by patients. (wiley.com)
  • Conclusion: Results from this substudy showed advantages of MF-VEP over FF-VEP in multicenter studies of central nervous system reparative therapies and provide novel evidence that fellow eye visual pathway amplitude loss occurs after optic neuritis but can potentially be prevented by opicinumab treatment. (elsevier.com)
  • Hood DC, Zhang X (2000) Multifocal ERG and VEP responses and visual fields: comparing disease-related changes. (springer.com)
  • Late evoked responses are generally used for studying higher cortical functions (eg, P300 in Alzheimer disease). (medscape.com)
  • Nevertheless, late evoked responses show promise and may make more inroads into clinical settings in the near future. (medscape.com)
  • Some centers have developed testing paradigms for olfactory and gustatory evoked responses as well. (medscape.com)
  • Significant correlations between the magnitude of the VEP parameters and MD of Humphrey static perimetry suggest that the impaired visual cortical responses observed in glaucoma patients can be revealed by both electrophysiological and psychophysical methods. (hindawi.com)
  • To allow a comparison of the visual‐field sensitivity to the mfVEP responses, estimates of sensitivity for each sector of the multifocal stimulus were obtained from the visual field values (total deviation). (pubmedcentralcanada.ca)
  • When 3-5 Hz Vm oscillations coincided with visual cues, excitatory neuron responses to preferred cues were significantly reduced. (jneurosci.org)
  • Although the serotonergic hallucinogen psilocybin activates multiple serotonin (5-HT) receptors, recent evidence suggests that activation of 5-HT2A receptors may lead to the formation of visual hallucinations by increasing cortical excitability and altering visual-evoked cortical responses. (nih.gov)
  • Using paired t-tests, significant differences were observed in several of the facial emotion evoked responses comparing OXT and placebo administration. (arvojournals.org)
  • Interictal abnormalities of gamma band activity in visual evoked responses in migraine: an indication of thalamocortical dysrhythmia? (wiley.com)
  • Coppola G, Ambrosini A, Di Clemente L, Magis D, Fumal A, Gérard P, Pierelli F & Schoenen J. Interictal abnormalities of gamma band activity in visual evoked responses in migraine: an indication of thalamocortical dysrhythmia? (wiley.com)
  • UPMC's electrophysiology and psychophysics service utilizes a variety of sophisticated technologies and methods to detect, diagnose and evaluate various visual disorders. (upmc.com)
  • The visual electrophysiology tests are objective and non-invasive and are compiled using ISCEV standards. (upmc.com)
  • The British Society for the Clinical Electrophysiology of Vision (BriSCEV) is the British chapter of ISCEV the International Society for Clinical Electrophysiology of Vision and the professional body for visual electrophysiology in the UK which was set up 17 years ago in Nottingham. (nuh.nhs.uk)
  • Purpose: To evaluate monkey multifocal visual evoked cortical potentials (mfVEPs) recorded from central and peripheral fields for reliability and isolation from electroretinographic (ERG) activity. (elsevier.com)
  • mfVEPs may be useful in animal models of diseases that differentially affect macular and peripheral visual field responsiveness. (elsevier.com)
  • Nasal Oxytocin produces emotion dependent effects on early visual evoked potentials. (arvojournals.org)
  • This study presents a method for accomplishing this by smoothly modulating the luminance of a visual stimulus using a stochastic process. (nih.gov)
  • Despite its visually unobtrusive nature, the rich statistical structure of the stimulus enables rapid estimation of the visual system's impulse response. (nih.gov)
  • Visual evoked potentials in parkinsonism and dopamine blockade reveal a stimulus-dependent dopamine function in humans. (bmj.com)
  • The detection of VEP abnormalities in Parkinson's disease was dependent on the spatial frequency of the visual stimulus (a vertical square wave grating). (bmj.com)
  • Dopamine precursor therapy differently reduced the VEP latency, depending on the spatial frequency of the visual stimulus. (bmj.com)
  • In addition, the attenuation of the late negativity could reflect a top-down feedback mechanism to suppress visual processing of an aversive stimulus. (lancs.ac.uk)
  • In de scriptie werd vooral gefocust op het bestuderen van de mVEP die een negatieve piek vertoont rond 200ms na stimulus en een postieve piek 250-300ms na stimulus. (scriptiebank.be)
  • Als bijdoelen hebben we het effect getest op de richting waarin de stimulus zich beweegd (links of rechts) en een hybride-BCI gecreërd die beide in een bewegende lijn (mVEP) en een kleurverandering (P300) respons teweegdbrengd. (scriptiebank.be)
  • A visual evoked potential is an evoked potential caused by a visual stimulus , such as an alternating checkerboard pattern on a computer screen . (myvmc.com)
  • Patients are asked to watch a television screen on which a visual stimulus is presented. (msu.edu)
  • An evoked potential is the electrical response of the brain to a sensory stimulus. (wikipedia.org)
  • In this method, by identifying a pseudorandom binary code (PRBC) that modulates visual stimulus from measured EEG, we can transfer the command related with the PRBC into external devices. (elsevier.com)
  • Methods: The mfVEP stimulus consisted of a 7-element hexagonal array that subtended 80 degrees of the central visual field. (elsevier.com)
  • Evoked potentials occur in response to a visual stimulus. (news-medical.net)
  • The "swinging flashlight test" detects a difference in the visual stimulus from each eye that reaches the efferent limb of the pupillary reflex when the two eyes are stimulated alternately ( Box 1 ). (mja.com.au)
  • Our findings also evidence that cortical processes combine information about the position of the stimulus on the retinae with information about the location of the eyes in their orbit as early as the stage of primary visual area. (biomedcentral.com)
  • When the retina is excited by a visual stimulus ranging from 3.5 Hz to 75 Hz, the brain generates electrical activity at the same (or multiples of) frequency of the visual stimulus. (wikipedia.org)
  • However, very few studies have combined bromazepam and event-related potentials (ERP). (scielo.br)
  • Through event-related potentials (ERPs), the present study examined the effect of postural control demands (PDs) on AIS central mechanisms related to SVV judgment and standing stability to elucidate the time-serial stability control process. (frontiersin.org)
  • To evaluate the diagnostic power of conventional, achromatic, automated perimetry (CAP), shortwavelength automated perimetry (SWAP), frequency-doubling technology (FDT) perimetry, and visual evoked potentials (VEP) in a group of patients with multiple sclerosis (MS) with or without a history of optic neuritis. (eur-j-ophthalmol.com)
  • VEP can be used to determine the visual potential and visual acuities of infants and non-verbal adults, evaluate neurological diseases such as multiple sclerosis, optic neuritis, amblyopia, cortical blindness. (upmc.com)
  • Evaluation of optic neuropathy in multiple sclerosis using low-contrast visual evoked potentials. (medscape.com)
  • However, the evoked potentials test can sometimes confirm a diagnosis of multiple sclerosis. (nhrmc.org)
  • To verify the relationship between intracranial pressure and flash visual evoked potentials (F-VEP) in patients with cryptococcal meningitis. (scielo.br)
  • 4 ] It is of interest to observe if visual evoked potentials (VEP) are also affected in these patients due to similar pathogenesis involving peripheral neuropathy and brain stem auditory evoked potential abnormalities. (pubmedcentralcanada.ca)
  • Humans are able to perceive symmetry information in the visual environment rapidly and efficiently. (eurekaselect.com)
  • Alwin M. Sambul, Nobuki Murayama and Tomohiko Igasaki, "Symmetry-Correlated Component in the Visual-Evoked Potential: Electrophysiological Study of Visual Symmetry Perception in Humans", Neuroscience and Biomedical Engineering (Discontinued) (2015) 3: 2. (eurekaselect.com)
  • Interhemispheric transfer of visual information in humans: the role of different callosal channels. (medscape.com)
  • We used an experimental design based on pattern-onset visual evoked potentials (VEP) recordings to study the effect of eye position on V1 activity in humans. (biomedcentral.com)
  • A machine records brain waves related to the nerves that make up the visual pathway. (medicalcityhospital.com)
  • Visual evoked potentials of Niemann-Pick type C1 mice reveal an impairment of the visual pathway that is rescued by 2-hydroxypropyl-ß-cyclodextrin. (nih.gov)
  • The aim of this study is to investigate the usefulness of visual evoked potentials (VEP) in patients with pineal gland cyst due to the possible compression on the visual pathway. (springermedizin.at)
  • VEP serve as a useful method to determine functional impairment of the visual pathway in patients with pineal gland cyst. (springermedizin.at)
  • Our data suggest affection of the human visual pathway in MHI. (elsevier.com)
  • PR-VEP recording seems to be a useful, objective, noninvasive tool, helping to identify possible subclinical affections of the visual pathway in MHI. (elsevier.com)
  • Horn FK, Michelson G, Schnitzler E. Visual evoked potentials of the blue-sensitive pathway under cold provocation in normals and glaucomas. (medscape.com)
  • In electrophysiological studies of the visual pathway in non-human primates we study the primitive "koniocellular" visual pathway and its relation to the well-understood parvocellular and magnocellular pathways. (edu.au)
  • Neuroimaging studies have revealed eye position-dependent activity in extrastriate visual, parietal and frontal areas that is along the visuo-motor pathway. (biomedcentral.com)
  • The mechanical effects of ICH on the central visual projection pathways, together with the repercussions on brain perfusion, may slow neuronal conduction, which could be demonstrated through evoked potential testing. (scielo.br)
  • This genuine optimised monitoring in France, set up in association with Metrovision company, should help increasing intraoperative VEP reliability as a monitoring tool for visual pathways function. (clinicaltrials.gov)
  • The Brainstem Auditory Evoked Potential (BAEP) assists in evaluating the auditory nerve pathways from the ears through the brainstem. (capitalhealth.org)
  • Our research aims to better understand the way visual information is transferred from the eye to the brain in segregated pathways for colour, motion and shape. (edu.au)
  • Organization of the Central Visual Pathways Following Field Defects Arising from Congenital, Inherited, and Acquired Eye Disease. (york.ac.uk)
  • The mean P100 visual-evoked potential latencies of the right and left eyes of each patient were calculated and used for the analysis. (ajnr.org)
  • The effect of oral prednisolone on visual evoked potential latencies in acute optic neuritis monitored in a prospective, randomized, controlled study. (medscape.com)
  • We evaluated the effect of prenatal methylmercury exposure on visual evoked potential (VEP) latencies in Faroese children with elevated prenatal methylmercury exposure. (elsevier.com)
  • We used multiple regression analysis to evaluate the association of mercury concentrations in cord blood and maternal hair at parturition with VEP latencies after adjustment for potential confounders that included the cord-serum phospholipid concentration of n-3 polyunsaturated fatty acids (PUFAs) and the duration of breastfeeding. (elsevier.com)
  • Visual evoked potentials is an important visual electrophysiological tool which has been used for the evaluation of visual field defects in primary open-angle glaucoma and is an appropriate objective measure of optic nerve function. (hindawi.com)
  • Electrophysiological tests like visual evoked potentials can contribute to detection of glaucomatous optic neuropathy since they are compatible with the functions of retinal ganglion cells, and they make it possible to study different aspects of visual functions. (hindawi.com)
  • Isofluorane has been widely used for recovery experiments, including visual electrophysiological studies, in rodents. (arvojournals.org)
  • An electrophysiological method for detecting visual toxicity in unrestrained rats. (semanticscholar.org)
  • A visual evoked potential is an electrophysiological test that is designed to measure the function of the optic nerves. (msu.edu)
  • Sensory evoked potentials have been widely used in clinical diagnostic medicine since the 1970s, and also in intraoperative neurophysiology monitoring (IONM), also known as surgical neurophysiology. (wikipedia.org)
  • Understand the diagnostic value and limitations of evoked potential techniques. (aston.ac.uk)
  • Evoked potentials: Diagnostic test evaluating specific tracts of the central and peripheral nervous system. (wikipedia.org)
  • This paper summarizes many of the studies pertaining to the significance of visual evoked potentials in the assessment of visual field defects in primary open-angle glaucoma. (hindawi.com)
  • The assessment of visual field defects with visual evoked potential has been a hard task. (hindawi.com)
  • Frequency doubling perimetry, in particular, proved to be an easy, fast, and sensitive technique in the assessment of patients with MS. Our results also suggest that subclinical visual involvement in MS can be better diagnosed using multiple (neurophysiologic and psychophysical) tests. (eur-j-ophthalmol.com)
  • Assessment of neurotoxicity of clioquinol (Enterovioform) by visual evoked potentials. (bvsalud.org)
  • HFA however does not selectively reveal which structures contribute to the impairment of the visual system observed in glaucoma. (hindawi.com)
  • To assess whether patients having stable chronic obstructive pulmonary disease (COPD) with no clinical evidence of visual impairment or peripheral neuropathy have visual evoked potentials (VEP) abnormalities on electrophysiologic evaluation. (pubmedcentralcanada.ca)
  • Care for eye conditions and visual impairment begins with a precise diagnosis. (childrenshospital.org)
  • Visual impairment in one eye only localises the abnormality to either the eye or the optic nerve. (mja.com.au)
  • Differential diagnoses of unilateral visual impairment localised clinically to the optic nerve are summarised in Box 2 . (mja.com.au)
  • Fractional anisotropy, radial diffusivity, and axial diffusivity were calculated and correlated with mean P100 visual-evoked potentials by tract-based spatial statistics. (ajnr.org)
  • Significant negative correlations between mean P100 visual-evoked potentials and fractional anisotropy and significant positive correlations between mean P100 visual-evoked potentials and radial diffusivity were found widespread over the whole brain. (ajnr.org)
  • Significant positive correlations between mean P100 visual-evoked potentials and axial diffusivity were less widespread, notably sparing the optic radiation. (ajnr.org)
  • Microstructural changes of the whole brain correlated significantly with mean P100 visual-evoked potentials. (ajnr.org)
  • This finding suggests a stronger correlation of mean P100 visual-evoked potentials to demyelination than to axonal damage. (ajnr.org)
  • Increased peak time of the visual P100 waveform is an expression of structural damage at the level of myelinated optic nerve fibres. (aston.ac.uk)
  • Although the VEP is very useful for detecting an anterior visual conduction disturbance, it is not specific with regard to etiology. (medscape.com)
  • Thus evoked compound motor action potentials (CMAP) or sensory nerve action potentials (SNAP) as used in nerve conduction studies (NCS) are generally not thought of as evoked potentials, though they do meet the above definition. (wikipedia.org)
  • This course is for you if you are looking to develop your knowledge in nerve conduction studies and evoked potentials in clinical practice. (aston.ac.uk)
  • You will explore topics such as nerve conduction studies and evoked potential measurements. (aston.ac.uk)
  • This module will introduce you to the underlying theory of carrying out nerve conduction studies, evoked potentials and your role in clinical practice. (aston.ac.uk)
  • Physiologists perform the majority of EEGs, evoked potentials and a portion of the nerve conduction studies. (wikipedia.org)
  • Whereas a clinical neurophysiologist is trained to perform all the following studies EEG, intraoperative monitoring, nerve conduction studies, EMG and evoked potentials, and electrodiagnostic physician focuses mainly on nerve conduction studies, needle EMG, and evoked potentials. (wikipedia.org)
  • Chromatic visual evoked potential (cVEPs) and psychophysics are often used to characterize isolated color or cone-opponent systems for various purposes. (arvojournals.org)
  • The functional effect of the pineal gland cyst is difficult to evaluate with visual field examination. (springermedizin.at)
  • The purpose of this study was to evaluate correlations of visual-evoked potentials with microstructural brain changes as determined by DTI in patients with demyelinating central nervous disease. (ajnr.org)
  • Flash and steady state visual evoked potential are measured during the surgical procedure at different times. (clinicaltrials.gov)
  • Towards an independent brain-computer interface using steady state visual evoked potentials. (neurotechcenter.org)
  • Brain-computer interface (BCI) systems using steady state visual evoked potentials (SSVEPs) have allowed healthy subjects to communicate. (neurotechcenter.org)
  • Thus the clinical diagnosis of POAG is commonly based on increase in intraocular pressure, characteristic optic nerve head cupping, and typical visual field defects which are assessed by standard static threshold perimetry, using an automated system such as Humphrey field analyzer (HFA). (hindawi.com)
  • Acute optic neuritis (ON) is often followed by recovery of visual function, 1 even if accompanied by significant optic nerve atrophy. (arvojournals.org)
  • Aim To investigate optic nerve function using the pattern-reversed visual evoked cortical potentials (VECP) before and after bony orbital decompression in dysthyroid optic neuropathy (DON) due to Graves' disease. (bmj.com)
  • Atilla H, Tekeli O, Ornek K. Pattern electroretinography and visual evoked potentials in optic nerve diseases. (medscape.com)
  • The early optic nerve involvement might explain some of the visual complain in this group of diabetic patients. (openophthalmologyjournal.com)
  • This study pinpoints the analysis of VEP response as a potentially accurate and non-invasive approach to assess neural activity and visual information processing in NPC1 patients, as well as for monitoring the progression of the disease and assessing the efficacy of potential therapies. (nih.gov)
  • Visual Evoked Potentials are used to assess integrity and maturation of the visual systems. (upmc.com)
  • Secondly, to assess whether the central nervous system (CNS) and in particular visual function is affected by type and/or duration of DM. (aston.ac.uk)
  • In this lab, learners record extracellular action potentials from the ventral nerve cord of a cockroach, or similar insect. (adinstruments.com)
  • In this lab, learners obtain extracellular recordings of action potentials from an anesthetized earthworm (Lumbricus terrestris). (adinstruments.com)
  • Available at: http://www.hopkinsmedicine.org/healthlibrary/test%5Fprocedures/neurological/evoked%5Fpotentials%5Fstudies%5F92,P07658. (medicalcityhospital.com)
  • Evoked Potentials are helpful in evaluating a number of different neurological problems including spinal cord injuries, acoustic neuroma, and optic neuritis. (capitalhealth.org)
  • However, it can potentially affect visual evoked potential (VEP) recordings due to GABAergic activity associated with it and subsequent burst suppression on the electroencephalogram response. (arvojournals.org)
  • Door een visuele stimulans te presenteren aan de patient zoals bijvoorbeeld een bewegende lijn (motion Visual Evoked Potentials (mVEP)) of een plots anderskleurig beeld (P300 "oddball") kunnen we met EEG een piek meten die een constant tijds patroon vertoond afhankelijk van het moment van stimulatie. (scriptiebank.be)
  • Ook bleek dat een hybride-BCI met mVEP en P300 tesamen afgeraden zou moeten worden aangezien de accuraatheid van het algoritme niet verbeterde en de P300 belastend is voor de ogen van de patient. (scriptiebank.be)
  • Color vision was evaluated clinically with the Ishihara test and the Farnsworth-Munsell 100 hue (FM 100 hue) test and electrophysiologically with chromatic visual evoked potentials (cVEPs). (osapublishing.org)
  • Such loss develops in the presence of open anterior chamber angles, characteristic visual field abnormalities, and intraocular tension that is too high for the continued health of the eye. (hindawi.com)
  • The range and incidence of visual and neurodevelopmental abnormalities at six months of age is described, and how these relate to a history of NAS and the pattern of in utero drug exposure is explored. (gla.ac.uk)
  • Manca Tekavčič Pompe, Jelka Brecelj, and Branka Stirn Kranjc, "Chromatic visual evoked potentials in young patients with demyelinating disease," J. Opt. (osapublishing.org)
  • Parisi V, Miglior S, Manni G. Clinical ability of pattern electroretinograms and visual evoked potentials in detecting visual dysfunction in ocular hypertension and glaucoma. (medscape.com)
  • Impaired visual development has been reported in infants born to mothers prescribed methadone in pregnancy. (aappublications.org)
  • Visual evoked potentials are small and immature in infants exposed to methadone and other drugs of misuse in utero. (aappublications.org)
  • This test can be used for infants or pre-veral children vision screening which is crucial to health visual development. (upmc.com)
  • Comparison of the neonatal VEP results with behavioral data from 5-week-old infants, suggests little change in visual performance over the first month of life. (ox.ac.uk)
  • The new method appears to provide a useful alternative to standard VEP methods, and to have potential application both in clinical practice and to the study of sensory and perceptual functions. (nih.gov)
  • The results of this study demonstrate their efficacy also in detecting early visual field deficits in MS patients without clinical signs of optic neuropathy. (eur-j-ophthalmol.com)
  • The Bifocal study looked at the effects of wearing bifocal spectacles on near visual functions, such as accommodation (focusing). (cardiff.ac.uk)
  • The purpose of this study was to discover whether anything is disrupting this flow of visual information in children with Down's syndrome. (cardiff.ac.uk)
  • In agreement with neuropsychological findings, the present study suggests that prenatal methylmercury exposure may have an adverse effect on VEP findings despite the absence of clinical toxicity to the visual system. (elsevier.com)
  • What is a sensory evoked potentials study? (nhrmc.org)
  • Why might I need a sensory evoked potentials study? (nhrmc.org)
  • What are the risks of a sensory evoked potentials study? (nhrmc.org)
  • How do I get ready for a sensory evoked potentials study? (nhrmc.org)
  • The goal of this study is to determine the optimal stimulating and recording protocol for visual evoked potentials (VEP's) during non-cranial surgery using total intravenous anesthesia (TIVA). (mayo.edu)
  • Faster and less obtrusive means for measuring a Visual Evoked Potential would be valuable in clinical testing and basic neuroscience research. (nih.gov)