Visual cortex. Medical search

Area of the OCCIPITAL LOBE concerned with the processing of visual information relayed via VISUAL PATHWAYS.

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.

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.

Investigative technique commonly used during ELECTROENCEPHALOGRAPHY in which a series of bright light flashes or visual patterns are used to elicit brain activity.

The total area or space visible in a person's peripheral vision with the eye looking straightforward.

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.

Imaging techniques used to colocalize sites of brain functions or physiological activity with brain structures.

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 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)

The absence or restriction of the usual external sensory stimuli to which the individual responds.

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.

The rostral part of the frontal lobe, bounded by the inferior precentral fissure in humans, which receives projection fibers from the MEDIODORSAL NUCLEUS OF THE THALAMUS. The prefrontal cortex receives afferent fibers from numerous structures of the DIENCEPHALON; MESENCEPHALON; and LIMBIC SYSTEM as well as cortical afferents of visual, auditory, and somatic origin.

Mental process to visually perceive a critical number of facts (the pattern), such as characters, shapes, displays, or designs.

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.

Images seen by one eye.

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.

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.

Awareness of oneself in relation to time, place and person.

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.

The region of the cerebral cortex that receives the auditory radiation from the MEDIAL GENICULATE BODY.

The process in which light signals are transformed by the PHOTORECEPTOR CELLS into electrical signals which can then be transmitted to the brain.

Area of the FRONTAL LOBE concerned with primary motor control located in the dorsal PRECENTRAL GYRUS immediately anterior to the central sulcus. It is comprised of three areas: the primary motor cortex located on the anterior paracentral lobule on the medial surface of the brain; the premotor cortex located anterior to the primary motor cortex; and the supplementary motor area located on the midline surface of the hemisphere anterior to the primary motor cortex.

Area of the parietal lobe concerned with receiving sensations such as movement, pain, pressure, position, temperature, touch, and vibration. It lies posterior to the central sulcus.

The capacity of the NERVOUS SYSTEM to change its reactivity as the result of successive activations.

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.

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.

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.

The awareness of the spatial properties of objects; includes physical space.

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.

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 blending of separate images seen by each eye into one composite image.

Abrupt changes in the membrane potential that sweep along the CELL MEMBRANE of excitable cells in response to excitation stimuli.

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.

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 coordination of a sensory or ideational (cognitive) process and a motor activity.

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.

Neural tracts connecting one part of the nervous system with another.

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.

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.

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.

The positioning and accommodation of eyes that allows the image to be brought into place on the FOVEA CENTRALIS of each eye.

Processes and properties of the EYE as a whole or of any of its parts.

Posterior portion of the CEREBRAL HEMISPHERES responsible for processing visual sensory information. It is located posterior to the parieto-occipital sulcus and extends to the preoccipital notch.

The function of opposing or restraining the excitation of neurons or their target excitable cells.

The sensory discrimination of a pattern shape or outline.

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.

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.

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 absence of light.

Voluntary or reflex-controlled movements of the eye.

Differential response to different stimuli.

Dominance of one cerebral hemisphere over the other in cerebral functions.

Method of measuring and mapping the scope of vision, from central to peripheral of each eye.

An outbred strain of rats developed in 1915 by crossing several Wistar Institute white females with a wild gray male. Inbred strains have been derived from this original outbred strain, including Long-Evans cinnamon rats (RATS, INBRED LEC) and Otsuka-Long-Evans-Tokushima Fatty rats (RATS, INBRED OLETF), which are models for Wilson's disease and non-insulin dependent diabetes mellitus, respectively.

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.

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).

Signals for an action; that specific portion of a perceptual field or pattern of stimuli to which a subject has learned to respond.

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.

Elements of limited time intervals, contributing to particular results or situations.

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.

Specialized junctions at which a neuron communicates with a target cell. At classical synapses, a neuron's presynaptic terminal releases a chemical transmitter stored in synaptic vesicles which diffuses across a narrow synaptic cleft and activates receptors on the postsynaptic membrane of the target cell. The target may be a dendrite, cell body, or axon of another neuron, or a specialized region of a muscle or secretory cell. Neurons may also communicate via direct electrical coupling with ELECTRICAL SYNAPSES. Several other non-synaptic chemical or electric signal transmitting processes occur via extracellular mediated interactions.

Cerebral cortex region on the medial aspect of the PARAHIPPOCAMPAL GYRUS, immediately caudal to the OLFACTORY CORTEX of the uncus. The entorhinal cortex is the origin of the major neural fiber system afferent to the HIPPOCAMPAL FORMATION, the so-called PERFORANT PATHWAY.

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.

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 minimum amount of stimulus energy necessary to elicit a sensory response.

Perception of three-dimensionality.

Use of electric potential or currents to elicit biological responses.

A genus of the family Lorisidae having four species which inhabit the forests and bush regions of Africa south of the Sahara and some nearby islands. The four species are G. alleni, G. crassicaudatus, G. demidovii, and G. senegalensis. There is another genus, Euoticus, containing two species which some authors have included in the Galago genus.

A statistical technique that isolates and assesses the contributions of categorical independent variables to variation in the mean of a continuous dependent variable.

The anterior pair of the quadrigeminal bodies which coordinate the general behavioral orienting responses to visual stimuli, such as whole-body turning, and reaching.

Use of sound to elicit a response in the nervous system.

The part of the cerebral hemisphere anterior to the central sulcus, and anterior and superior to the lateral sulcus.

The misinterpretation of a real external, sensory experience.

Electrodes with an extremely small tip, used in a voltage clamp or other apparatus to stimulate or record bioelectric potentials of single cells intracellularly or extracellularly. (Dorland, 28th ed)

The outer zone of the KIDNEY, beneath the capsule, consisting of KIDNEY GLOMERULUS; KIDNEY TUBULES, DISTAL; and KIDNEY TUBULES, PROXIMAL.

A technique that involves the use of electrical coils on the head to generate a brief magnetic field which reaches the CEREBRAL CORTEX. It is coupled with ELECTROMYOGRAPHY response detection to assess cortical excitability by the threshold required to induce MOTOR EVOKED POTENTIALS. This method is also used for BRAIN MAPPING, to study NEUROPHYSIOLOGY, and as a substitute for ELECTROCONVULSIVE THERAPY for treating DEPRESSION. Induction of SEIZURES limits its clinical usage.

The surgical removal of the eyeball leaving the eye muscles and remaining orbital contents intact.

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.

Low molecular weight, calcium binding muscle proteins. Their physiological function is possibly related to the contractile process.

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.

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.

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.

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.

Projection neurons in the CEREBRAL CORTEX and the HIPPOCAMPUS. Pyramidal cells have a pyramid-shaped soma with the apex and an apical dendrite pointed toward the pial surface and other dendrites and an axon emerging from the base. The axons may have local collaterals but also project outside their cortical region.

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.

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.

An illusion of vision usually affecting spatial relations.

The process whereby auditory stimuli are selected, organized, and interpreted by the organism.

The superficial GRAY MATTER of the CEREBELLUM. It consists of two main layers, the stratum moleculare and the stratum granulosum.

An abrupt voluntary shift in ocular fixation from one point to another, as occurs in reading.

The study of systems which respond disproportionately (nonlinearly) to initial conditions or perturbing stimuli. Nonlinear systems may exhibit "chaos" which is classically characterized as sensitive dependence on initial conditions. Chaotic systems, while distinguished from more ordered periodic systems, are not random. When their behavior over time is appropriately displayed (in "phase space"), constraints are evident which are described by "strange attractors". Phase space representations of chaotic systems, or strange attractors, usually reveal fractal (FRACTALS) self-similarity across time scales. Natural, including biological, systems often display nonlinear dynamics and chaos.

Refers to animals in the period of time just after birth.

Surgically placed electric conductors through which ELECTRIC STIMULATION is delivered to or electrical activity is recorded from a specific point inside the body.

The non-genetic biological changes of an organism in response to challenges in its ENVIRONMENT.

Mental processing of chromatic signals (COLOR VISION) from the eye by the VISUAL CORTEX where they are converted into symbolic representations. Color perception involves numerous neurons, and is influenced not only by the distribution of wavelengths from the viewed object, but also by its background color and brightness contrast at its boundary.

Paired bodies containing mostly GRAY MATTER and forming part of the lateral wall of the THIRD VENTRICLE of the brain.

The communication from a NEURON to a target (neuron, muscle, or secretory cell) across a SYNAPSE. In chemical synaptic transmission, the presynaptic neuron releases a NEUROTRANSMITTER that diffuses across the synaptic cleft and binds to specific synaptic receptors, activating them. The activated receptors modulate specific ion channels and/or second-messenger systems in the postsynaptic cell. In electrical synaptic transmission, electrical signals are communicated as an ionic current flow across ELECTRICAL SYNAPSES.

The anterior portion of the head that includes the skin, muscles, and structures of the forehead, eyes, nose, mouth, cheeks, and jaw.

The only family of the order SCANDENTIA, variously included in the order Insectivora or in the order Primates, and often in the order Microscelidea, consisting of five genera. They are TUPAIA, Ananthana (Indian tree shrew), Dendrogale (small smooth-tailed tree shrew), Urogale (Mindanao tree shrew), and Ptilocercus (pen-tailed tree shrew). The tree shrews inhabit the forest areas of eastern Asia from India and southwestern China to Borneo and the Philippines.

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)

A suborder of PRIMATES consisting of six families: CEBIDAE (some New World monkeys), ATELIDAE (some New World monkeys), CERCOPITHECIDAE (Old World monkeys), HYLOBATIDAE (gibbons and siamangs), CALLITRICHINAE (marmosets and tamarins), and HOMINIDAE (humans and great apes).

EEG phase synchronization of the cortical brain region (CEREBRAL CORTEX).

The most common inhibitory neurotransmitter in the central nervous system.

Sensation of making physical contact with objects, animate or inanimate. Tactile stimuli are detected by MECHANORECEPTORS in the skin and mucous membranes.

The gradual irreversible changes in structure and function of an organism that occur as a result of the passage of time.

Learning that is manifested in the ability to respond differentially to various stimuli.

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.

Extensions of the nerve cell body. They are short and branched and receive stimuli from other NEURONS.

Optical imaging techniques used for recording patterns of electrical activity in tissues by monitoring transmembrane potentials via FLUORESCENCE imaging with voltage-sensitive fluorescent dyes.

Relatively permanent change in behavior that is the result of past experience or practice. The concept includes the acquisition of knowledge.

Depolarization of membrane potentials at the SYNAPTIC MEMBRANES of target neurons during neurotransmission. Excitatory postsynaptic potentials can singly or in summation reach the trigger threshold for ACTION POTENTIALS.

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)

The outer layer of the adrenal gland. It is derived from MESODERM and comprised of three zones (outer ZONA GLOMERULOSA, middle ZONA FASCICULATA, and inner ZONA RETICULARIS) with each producing various steroids preferentially, such as ALDOSTERONE; HYDROCORTISONE; DEHYDROEPIANDROSTERONE; and ANDROSTENEDIONE. Adrenal cortex function is regulated by pituitary ADRENOCORTICOTROPIN.

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)

Wave-like oscillations of electric potential between parts of the brain recorded by EEG.

A calbindin protein that is differentially expressed in distinct populations of NEURONS throughout the vertebrate and invertebrate NERVOUS SYSTEM, and modulates intrinsic neuronal excitability and influences LONG-TERM POTENTIATION. It is also found in LUNG, TESTIS, OVARY, KIDNEY, and BREAST, and is expressed in many tumor types found in these tissues. It is often used as an immunohistochemical marker for MESOTHELIOMA.

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)

One of the convolutions on the medial surface of the CEREBRAL HEMISPHERES. It surrounds the rostral part of the brain and CORPUS CALLOSUM and forms part of the LIMBIC SYSTEM.

The knowledge or perception that someone or something present has been previously encountered.

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.

Remembrance of information for a few seconds to hours.

A genus of the subfamily CALLITRICHINAE occurring in forests of Brazil and Bolivia and containing seventeen species.

The interference of one perceptual stimulus with another causing a decrease or lessening in perceptual effectiveness.

Computer-assisted processing of electric, ultrasonic, or electronic signals to interpret function and activity.

The sensory interpretation of the dimensions of objects.

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.

Nerve fibers that are capable of rapidly conducting impulses away from the neuron cell body.

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.

Most generally any NEURONS which are not motor or sensory. Interneurons may also refer to neurons whose AXONS remain within a particular brain region in contrast to projection neurons, which have axons projecting to other brain regions.

A state in which there is an enhanced potential for sensitivity and an efficient responsiveness to external stimuli.

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.

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).

The visually perceived property of objects created by absorption or reflection of specific wavelengths of light.

That portion of the electromagnetic spectrum in the visible, ultraviolet, and infrared range.

The circulation of blood through the BLOOD VESSELS of the BRAIN.

A persistent activity-dependent decrease in synaptic efficacy between NEURONS. It typically occurs following repeated low-frequency afferent stimulation, but it can be induced by other methods. Long-term depression appears to play a role in MEMORY.

Stiff hairs projecting from the face around the nose of most mammals, acting as touch receptors.

A series of tests used to assess various functions of the eyes.

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 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.

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.)

A class of ionotropic glutamate receptors characterized by affinity for N-methyl-D-aspartate. NMDA receptors have an allosteric binding site for glycine which must be occupied for the channel to open efficiently and a site within the channel itself to which magnesium ions bind in a voltage-dependent manner. The positive voltage dependence of channel conductance and the high permeability of the conducting channel to calcium ions (as well as to monovalent cations) are important in excitotoxicity and neuronal plasticity.

Act of eliciting a response from a person or organism through physical contact.

The lectin wheatgerm agglutinin conjugated to the enzyme HORSERADISH PEROXIDASE. It is widely used for tracing neural pathways.

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 detailed examination of observable activity or behavior associated with the execution or completion of a required function or unit of work.

Devices that help people with impaired sensory responses.

The electrical properties, characteristics of living organisms, and the processes of organisms or their parts that are involved in generating and responding to electrical charges.

A genus of the family CEBIDAE consisting of four species: S. boliviensis, S. orstedii (red-backed squirrel monkey), S. sciureus (common squirrel monkey), and S. ustus. They inhabit tropical rain forests in Central and South America. S. sciureus is used extensively in research studies.

Several groups of nuclei in the thalamus that serve as the major relay centers for sensory impulses in the brain.

The scientific discipline concerned with the physiology of the nervous system.

A convolution on the inferior surface of each cerebral hemisphere, lying between the hippocampal and collateral sulci.

A pyridoxal-phosphate protein that catalyzes the alpha-decarboxylation of L-glutamic acid to form gamma-aminobutyric acid and carbon dioxide. The enzyme is found in bacteria and in invertebrate and vertebrate nervous systems. It is the rate-limiting enzyme in determining GAMMA-AMINOBUTYRIC ACID levels in normal nervous tissues. The brain enzyme also acts on L-cysteate, L-cysteine sulfinate, and L-aspartate. EC 4.1.1.15.

Partial or total removal, ablation, or destruction of the cerebral cortex; may be chemical. It is not used with animals that do not possess a cortex, i.e., it is used only with mammals.

Intellectual or mental process whereby an organism obtains knowledge.

A strain of albino rat used widely for experimental purposes because of its calmness and ease of handling. It was developed by the Sprague-Dawley Animal Company.

Nerve structures through which impulses are conducted from a peripheral part toward a nerve center.

The directed transport of ORGANELLES and molecules along nerve cell AXONS. Transport can be anterograde (from the cell body) or retrograde (toward the cell body). (Alberts et al., Molecular Biology of the Cell, 3d ed, pG3)

Adjustment of the eyes under conditions of low light. The sensitivity of the eye to light is increased during dark adaptation.

A calbindin protein found in many mammalian tissues, including the UTERUS, PLACENTA, BONE, PITUITARY GLAND, and KIDNEYS. In intestinal ENTEROCYTES it mediates intracellular calcium transport from apical to basolateral membranes via calcium binding at two EF-HAND MOTIFS. Expression is regulated in some tissues by VITAMIN D.

A procedure consisting of a sequence of algebraic formulas and/or logical steps to calculate or determine a given task.

An electrophysiologic technique for studying cells, cell membranes, and occasionally isolated organelles. All patch-clamp methods rely on a very high-resistance seal between a micropipette and a membrane; the seal is usually attained by gentle suction. The four most common variants include on-cell patch, inside-out patch, outside-out patch, and whole-cell clamp. Patch-clamp methods are commonly used to voltage clamp, that is control the voltage across the membrane and measure current flow, but current-clamp methods, in which the current is controlled and the voltage is measured, are also used.

A species of macaque monkey that mainly inhabits the forest of southern India. They are also called bonnet macaques or bonnet monkeys.

The making of a radiograph of an object or tissue by recording on a photographic plate the radiation emitted by radioactive material within the object. (Dorland, 27th ed)

Sense of awareness of self and of the environment.

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.

Broad plate of dense myelinated fibers that reciprocally interconnect regions of the cortex in all lobes with corresponding regions of the opposite hemisphere. The corpus callosum is located deep in the longitudinal fissure.

A persistent increase in synaptic efficacy, usually induced by appropriate activation of the same synapses. The phenomenological properties of long-term potentiation suggest that it may be a cellular mechanism of learning and memory.

The largest portion of the CEREBRAL CORTEX in which the NEURONS are arranged in six layers in the mammalian brain: molecular, external granular, external pyramidal, internal granular, internal pyramidal and multiform layers.

A new pattern of perceptual or ideational material derived from past experience.

A mechanism of communicating one's own sensory system information about a task, movement or skill.

A multisubunit enzyme complex containing CYTOCHROME A GROUP; CYTOCHROME A3; two copper atoms; and 13 different protein subunits. It is the terminal oxidase complex of the RESPIRATORY CHAIN and collects electrons that are transferred from the reduced CYTOCHROME C GROUP and donates them to molecular OXYGEN, which is then reduced to water. The redox reaction is simultaneously coupled to the transport of PROTONS across the inner mitochondrial membrane.

Computer-based representation of physical systems and phenomena such as chemical processes.

Neurons which conduct NERVE IMPULSES to the CENTRAL NERVOUS SYSTEM.

Calcium-binding proteins that are found in DISTAL KIDNEY TUBULES, INTESTINES, BRAIN, and other tissues where they bind, buffer and transport cytoplasmic calcium. Calbindins possess a variable number of EF-HAND MOTIFS which contain calcium-binding sites. Some isoforms are regulated by VITAMIN D.

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 range or frequency distribution of a measurement in a population (of organisms, organs or things) that has not been selected for the presence of disease or abnormality.

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.

The point or frequency at which all flicker of an intermittent light stimulus disappears.

Application of statistical procedures to analyze specific observed or assumed facts from a particular study.

A neurotoxic isoxazole isolated from species of AMANITA. It is obtained by decarboxylation of IBOTENIC ACID. Muscimol is a potent agonist of GABA-A RECEPTORS and is used mainly as an experimental tool in animal and tissue studies.

A species of the genus MACACA which inhabits Malaya, Sumatra, and Borneo. It is one of the most arboreal species of Macaca. The tail is short and untwisted.

Continuous frequency distribution of infinite range. Its properties are as follows: 1, continuous, symmetrical distribution with both tails extending to infinity; 2, arithmetic mean, mode, and median identical; and 3, shape completely determined by the mean and standard deviation.

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 ability to respond to segments of the perceptual experience rather than to the whole.

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.

Brain waves characterized by a relatively high voltage or amplitude and a frequency of 8-13 Hz. They constitute the majority of waves recorded by EEG registering the activity of the parietal and occipital lobes when the individual is awake, but relaxed with the eyes closed.

The ability to estimate periods of time lapsed or duration of time.

Those affective states which can be experienced and have arousing and motivational properties.

The observable response of a man or animal to a situation.

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.

General term for a number of inherited defects of amino acid metabolism in which there is a deficiency or absence of pigment in the eyes, skin, or hair.

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.

Therapeutic introduction of ions of soluble salts into tissues by means of electric current. In medical literature it is commonly used to indicate the process of increasing the penetration of drugs into surface tissues by the application of electric current. It has nothing to do with ION EXCHANGE; AIR IONIZATION nor PHONOPHORESIS, none of which requires current.

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.

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.).

Vision: modular analysis--or not? (1/5702)

It has commonly been assumed that the many separate areas of the visual system perform modular analyses, each restricted to a single attribute of the image. A recent paper advocates a radically different approach, where all areas in the hierarchy analyse all attributes of the image to extract perceptually relevant decisions. (+info)

On the neural correlates of visual perception. (2/5702)

Neurological findings suggest that the human striate cortex (V1) is an indispensable component of a neural substratum subserving static achromatic form perception in its own right and not simply as a central distributor of retinally derived information to extrastriate visual areas. This view is further supported by physiological evidence in primates that the finest-grained conjoined representation of spatial detail and retinotopic localization that underlies phenomenal visual experience for local brightness discriminations is selectively represented at cortical levels by the activity of certain neurons in V1. However, at first glance, support for these ideas would appear to be undermined by incontrovertible neurological evidence (visual hemineglect and the simultanagnosias) and recent psychophysical results on 'crowding' that confirm that activation of neurons in V1 may, at times, be insufficient to generate a percept. Moreover, a recent proposal suggests that neural correlates of visual awareness must project directly to those in executive space, thus automatically excluding V1 from a related perceptual space because V1 lacks such direct projections. Both sets of concerns are, however, resolved within the context of adaptive resonance theories. Recursive loops, linking the dorsal lateral geniculate nucleus (LGN) through successive cortical visual areas to the temporal lobe by means of a series of ascending and descending pathways, provide a neuronal substratum at each level within a modular framework for mutually consistent descriptions of sensory data. At steady state, such networks obviate the necessity that neural correlates of visual experience project directly to those in executive space because a neural phenomenal perceptual space subserving form vision is continuously updated by information from an object recognition space equivalent to that destined to reach executive space. Within this framework, activity in V1 may engender percepts that accompany figure-ground segregations only when dynamic incongruities are resolved both within and between ascending and descending streams. Synchronous neuronal activity on a short timescale within and across cortical areas, proposed and sometimes observed as perceptual correlates, may also serve as a marker that a steady state has been achieved, which, in turn, may be a requirement for the longer time constants that accompany the emergence and stability of perceptual states compared to the faster dynamics of adapting networks and the still faster dynamics of individual action potentials. Finally, the same consensus of neuronal activity across ascending and descending pathways linking multiple cortical areas that in anatomic sequence subserve phenomenal visual experiences and object recognition may underlie the normal unity of conscious experience. (+info)

Transient and permanent deficits in motion perception after lesions of cortical areas MT and MST in the macaque monkey. (3/5702)

We examined the nature and the selectivity of the motion deficits produced by lesions of extrastriate areas MT and MST. Lesions were made by injecting ibotenic acid into the representation of the left visual field in two macaque monkeys. The monkeys discriminated two stimuli that differed either in stimulus direction or orientation. Direction and orientation discrimination were assessed by measuring thresholds with gratings and random-dots placed in the intact or lesioned visual fields. At the start of behavioral testing, we found pronounced, motion-specific deficits in thresholds for all types of moving stimuli, including pronounced elevations in contrast thresholds and in signal-to-noise thresholds measured with moving gratings, as well as deficits in direction range thresholds and motion coherence measured with random-dot stimuli. In addition, the accuracy of direction discrimination was reduced at smaller spatial displacements (i.e. step sizes), suggesting an increase in spatial scale of the residual directional mechanism. Subsequent improvements in thresholds were seen with all motion stimuli, as behavioral training progressed, and these improvements occurred only with extensive behavioral testing in the lesioned visual field. These improvements were particularly pronounced for stimuli not masked by noise. On the other hand, deficits in the ability to extract motion from noisy stimuli and in the accuracy of direction discrimination persisted despite extensive behavioral training. These results demonstrate the importance of areas MT and MST for the perception of motion direction, particularly in the presence of noise. In addition, they provide evidence for the importance of behavioral training for functional recovery after cortical lesions. The data also strongly support the idea of functional specialization of areas MT and MST for motion processing. (+info)

Modulation of long-term synaptic depression in visual cortex by acetylcholine and norepinephrine. (4/5702)

In a slice preparation of rat visual cortex, we discovered that paired-pulse stimulation (PPS) elicits a form of homosynaptic long-term depression (LTD) in the superficial layers when carbachol (CCh) or norepinephrine (NE) is applied concurrently. PPS by itself, or CCh and NE in the absence of synaptic stimulation, produced no lasting change. The LTD induced by PPS in the presence of NE or CCh is of comparable magnitude with that obtained with prolonged low-frequency stimulation (LFS) but requires far fewer stimulation pulses (40 vs 900). The cholinergic facilitation of LTD was blocked by atropine and pirenzepine, suggesting involvement of M1 receptors. The noradrenergic facilitation of LTD was blocked by urapidil and was mimicked by methoxamine, suggesting involvement of alpha1 receptors. beta receptor agonists and antagonists were without effect. Induction of LTD by PPS was inhibited by NMDA receptor blockers (completely in the case of NE; partially in the case of CCh), suggesting that one action of the modulators is to control the gain of NMDA receptor-dependent homosynaptic LTD in visual cortex. We propose that this is a mechanism by which cholinergic and noradrenergic inputs to the neocortex modulate naturally occurring receptive field plasticity. (+info)

Competitive mechanisms subserve attention in macaque areas V2 and V4. (5/5702)

It is well established that attention modulates visual processing in extrastriate cortex. However, the underlying neural mechanisms are unknown. A consistent observation is that attention has its greatest impact on neuronal responses when multiple stimuli appear together within a cell's receptive field. One way to explain this is to assume that multiple stimuli activate competing populations of neurons and that attention biases this competition in favor of the attended stimulus. In the absence of competing stimuli, there is no competition to be resolved. Accordingly, attention has a more limited effect on the neuronal response to a single stimulus. To test this interpretation, we measured the responses of neurons in macaque areas V2 and V4 using a behavioral paradigm that allowed us to isolate automatic sensory processing mechanisms from attentional effects. First, we measured each cell's response to a single stimulus presented alone inside the receptive field or paired with a second receptive field stimulus, while the monkey attended to a location outside the receptive field. Adding the second stimulus typically caused the neuron's response to move toward the response that was elicited by the second stimulus alone. Then, we directed the monkey's attention to one element of the pair. This drove the neuron's response toward the response elicited when the attended stimulus appeared alone. These findings are consistent with the idea that attention biases competitive interactions among neurons, causing them to respond primarily to the attended stimulus. A quantitative neural model of attention is proposed to account for these results. (+info)

CRE-mediated gene transcription in neocortical neuronal plasticity during the developmental critical period. (6/5702)

Neuronal activity-dependent processes are believed to mediate the formation of synaptic connections during neocortical development, but the underlying intracellular mechanisms are not known. In the visual system, altering the pattern of visually driven neuronal activity by monocular deprivation induces cortical synaptic rearrangement during a postnatal developmental window, the critical period. Here, using transgenic mice carrying a CRE-lacZ reporter, we demonstrate that a calcium- and cAMP-regulated signaling pathway is activated following monocular deprivation. We find that monocular deprivation leads to an induction of CRE-mediated lacZ expression in the visual cortex preceding the onset of physiologic plasticity, and this induction is dramatically downregulated following the end of the critical period. These results suggest that CRE-dependent coordinate regulation of a network of genes may control physiologic plasticity during postnatal neocortical development. (+info)

MST neuronal responses to heading direction during pursuit eye movements. (7/5702)

As you move through the environment, you see a radial pattern of visual motion with a focus of expansion (FOE) that indicates your heading direction. When self-movement is combined with smooth pursuit eye movements, the turning of the eye distorts the retinal image of the FOE but somehow you still can perceive heading. We studied neurons in the medial superior temporal area (MST) of monkey visual cortex, recording responses to FOE stimuli presented during fixation and smooth pursuit eye movements. Almost all neurons showed significant changes in their FOE selective responses during pursuit eye movements. However, the vector average of all the neuronal responses indicated the direction of the FOE during both fixation and pursuit. Furthermore, the amplitude of the net vector increased with increasing FOE eccentricity. We conclude that neuronal population encoding in MST might contribute to pursuit-tolerant heading perception. (+info)

Retinotopic mapping of lateral geniculate nucleus in humans using functional magnetic resonance imaging. (8/5702)

Subcortical nuclei in the thalamus, which play an important role in many functions of the human brain, provide challenging targets for functional mapping with neuroimaging techniques because of their small sizes and deep locations. In this study, we explore the capability of high-resolution functional magnetic resonance imaging at 4 Tesla for mapping the retinotopic organization in the lateral geniculate nucleus (LGN). Our results show that the hemifield visual stimulation only activates LGN in the contralateral hemisphere, and the lower-field and upper-field visual stimulations activate the superior and inferior portion of LGN, respectively. These results reveal a similar retinotopic organization between the human and nonhuman primate LGN and between LGN and the primary visual cortex. We conclude that high-resolution functional magnetic resonance imaging is capable of functional mapping of suborganizations in small nuclei together with cortical activation. This will have an impact for studying the thalamocortical networks in the human brain. (+info)

There are different types of blindness, including:

1. Congenital blindness: Blindness that is present at birth, often due to genetic mutations or abnormalities in the development of the eye and brain.
2. Acquired blindness: Blindness that develops later in life due to injury, disease, or other factors.
3. Amblyopia: A condition where one eye has reduced vision due to misalignment or other causes.
4. Glaucoma: A group of eye conditions that can damage the optic nerve and lead to blindness if left untreated.
5. Retinitis pigmentosa: A degenerative disease that affects the retina and can cause blindness.
6. Cataracts: A clouding of the lens in the eye that can impair vision and eventually cause blindness if left untreated.
7. Macular degeneration: A condition where the macula, a part of the retina responsible for central vision, deteriorates and causes blindness.

There are various treatments and therapies for blindness, depending on the underlying cause. These may include medications, surgery, low vision aids, and assistive technology such as braille and audio books, screen readers, and voice-controlled software. Rehabilitation programs can also help individuals adapt to blindness and lead fulfilling lives.

Some common types of vision disorders include:

1. Myopia (nearsightedness): A condition where close objects are seen clearly, but distant objects appear blurry.
2. Hyperopia (farsightedness): A condition where distant objects are seen clearly, but close objects appear blurry.
3. Astigmatism: A condition where the cornea or lens of the eye is irregularly shaped, causing blurred vision at all distances.
4. Presbyopia: A condition that occurs as people age, where the lens of the eye loses flexibility and makes it difficult to focus on close objects.
5. Amblyopia (lazy eye): A condition where one eye has reduced vision due to abnormal development or injury.
6. Strabismus (crossed eyes): A condition where the eyes are misaligned and point in different directions.
7. Color blindness: A condition where people have difficulty perceiving certain colors, usually red and green.
8. Retinal disorders: Conditions that affect the retina, such as age-related macular degeneration, diabetic retinopathy, or retinal detachment.
9. Glaucoma: A group of conditions that damage the optic nerve, often due to increased pressure in the eye.
10. Cataracts: A clouding of the lens in the eye that can cause blurred vision and sensitivity to light.

Vision disorders can be diagnosed through a comprehensive eye exam, which includes a visual acuity test, refraction test, and dilated eye exam. Treatment options for vision disorders depend on the specific condition and may include glasses or contact lenses, medication, surgery, or a combination of these.

1. A false or misleading sensory experience, such as seeing a shape or color that is not actually present.
2. A delusion or mistaken belief that is not based on reality or evidence.
3. A symptom that is perceived by the patient but cannot be detected by medical examination or testing.
4. A feeling of being drugged, dizzy, or disoriented, often accompanied by hallucinations or altered perceptions.
5. A temporary and harmless condition caused by a sudden change in bodily functions or sensations, such as a hot flash or a wave of dizziness.
6. A false or mistaken belief about one's own health or medical condition, often resulting from misinterpretation of symptoms or self-diagnosis.
7. A psychological phenomenon in which the patient experiences a feeling of being in a different body or experiencing a different reality, such as feeling like one is in a dream or a parallel universe.
8. A neurological condition characterized by disturbances in sensory perception, such as seeing things that are not there ( hallucinations) or perceiving sensations that are not real.
9. A type of hysteria or conversion disorder in which the patient experiences physical symptoms without any underlying medical cause, such as numbness or paralysis of a limb.
10. A condition in which the patient has a false belief that they have a serious medical condition, often accompanied by excessive anxiety or fear.

ILLUSIONS IN MEDICINE

Illusions can be a significant challenge in medicine, as they can lead to misdiagnosis, mismanagement of symptoms, and unnecessary treatment. Here are some examples of how illusions can manifest in medical settings:

1. Visual illusions: A patient may see something that is not actually there, such as a shadow or a shape, which can be misinterpreted as a sign of a serious medical condition.
2. Auditory illusions: A patient may hear sounds or noises that are not real, such as ringing in the ears (tinnitus) or hearing voices.
3. Tactile illusions: A patient may feel sensations on their skin that are not real, such as itching or crawling sensations.
4. Olfactory illusions: A patient may smell something that is not there, such as a strange odor or a familiar scent that is not actually present.
5. Gustatory illusions: A patient may taste something that is not there, such as a metallic or bitter taste.
6. Proprioceptive illusions: A patient may feel sensations of movement or position changes that are not real, such as feeling like they are spinning or floating.
7. Interoceptive illusions: A patient may experience sensations in their body that are not real, such as feeling like their heart is racing or their breathing is shallow.
8. Cognitive illusions: A patient may have false beliefs about their medical condition or treatment, such as believing they have a serious disease when they do not.

THE NEUROSCIENCE OF ILLUSIONS

Illusions are the result of complex interactions between the brain and the sensory systems. Here are some key factors that contribute to the experience of illusions:

1. Brain processing: The brain processes sensory information and uses past experiences and expectations to interpret what is being perceived. This can lead to misinterpretation and the experience of illusions.
2. Sensory integration: The brain integrates information from multiple senses, such as vision, hearing, and touch, to create a unified perception of reality. Imbalances in sensory integration can contribute to the experience of illusions.
3. Attention: The brain's attention system plays a critical role in determining what is perceived and how it is interpreted. Attention can be directed towards certain stimuli or away from others, leading to the experience of illusions.
4. Memory: Past experiences and memories can influence the interpretation of current sensory information, leading to the experience of illusions.
5. Emotion: Emotional states can also affect the interpretation of sensory information, leading to the experience of illusions. For example, a person in a state of fear may interpret ambiguous sensory information as threatening.

THE TREATMENT OF ILLUSIONS

Treatment for illusions depends on the underlying cause and can vary from case to case. Some possible treatment options include:

1. Sensory therapy: Sensory therapy, such as vision or hearing therapy, may be used to improve sensory processing and reduce the experience of illusions.
2. Cognitive-behavioral therapy (CBT): CBT can help individuals identify and change negative thought patterns and behaviors that contribute to the experience of illusions.
3. Mindfulness training: Mindfulness training can help individuals develop greater awareness of their sensory experiences and reduce the influence of illusions.
4. Medication: In some cases, medication may be prescribed to treat underlying conditions that are contributing to the experience of illusions, such as anxiety or depression.
5. Environmental modifications: Environmental modifications, such as changing the lighting or reducing noise levels, may be made to reduce the stimulus intensity and improve perception.

CONCLUSION

Illusions are a common experience that can have a significant impact on our daily lives. Understanding the causes of illusions and seeking appropriate treatment can help individuals manage their symptoms and improve their quality of life. By working with a healthcare professional, individuals can develop a personalized treatment plan that addresses their specific needs and helps them overcome the challenges of illusions.

The amblyopic eye may have reduced visual sharpness and/or abnormal ocular alignment (strabismus). The other eye is generally normal or has better vision. Amblyopia is often present at birth but may not be noticed until the child is a few years old. It can also result from various conditions, such as strabismus, cataracts, or differences in the refractive error of the two eyes (anisometropic amblyopia).

The most common form of amblyopia is anisometropic amblyopia, which occurs when there is a significant difference in the refractive power between the two eyes. This can cause the brain to favor one eye over the other, leading to reduced vision in the amblyopic eye. Amblyopia can be treated with glasses or contact lenses, patching the better eye to force the weaker eye to work harder, or surgery to correct strabismus or anisometropia.

Early detection and treatment are important to prevent long-term visual impairment. However, amblyopia can sometimes persist even after treatment, and it is a leading cause of monocular vision in adults.

Scotoma is a term that was first used in the early 19th century to describe blind spots in the visual field caused by defects in the retina or optic nerve. Over time, the term has been broadened to include any type of blind spot or defect in the visual field, regardless of its cause.

There are several different types of scotomas, including:

1. Homonymous hemianopsia: A condition in which there is a blind spot in one side of both eyes, causing difficulty with recognizing objects and people on that side.
2. Hemianopia: A condition in which there is a blind spot in one half of both eyes, often caused by a stroke or brain injury.
3. Quadrantanopia: A condition in which there is a blind spot in one quarter of both eyes, often caused by a stroke or brain injury.
4. Scanning vision: A condition in which the visual field appears to be scanned or sectioned off, often caused by a brain disorder such as multiple sclerosis.
5. Blind spot scotoma: A condition in which there is a small blind spot in the central part of the visual field, often caused by a lesion in the retina or optic nerve.

Scotomas can have a significant impact on daily life, making it difficult to perform everyday tasks such as driving, reading, and recognizing faces. Treatment options for scotomas depend on the underlying cause and may include prism glasses, vision therapy, or surgery. In some cases, scotomas may be a sign of a more serious condition that requires medical attention.

There are several causes of hemianopsia, including:

1. Stroke or cerebral vasculitis: These conditions can damage the occipital lobe and result in hemianopsia.
2. Brain tumors: Tumors in the occipital lobe can cause hemianopsia by compressing or damaging the visual pathways.
3. Traumatic brain injury: A head injury can cause damage to the occipital lobe and result in hemianopsia.
4. Cerebral palsy: This condition can cause brain damage that leads to hemianopsia.
5. Multiple sclerosis: This autoimmune disease can cause damage to the visual pathways and result in hemianopsia.

Symptoms of hemianopsia may include:

1. Blindness or impaired vision in one side of both eyes.
2. Difficulty recognizing objects or people on one side of the visual field.
3. Inability to see objects that are peripheral to the affected side.
4. Difficulty with depth perception and spatial awareness.
5. Eye movements that are abnormal or restricted.

Diagnosis of hemianopsia typically involves a comprehensive eye exam, including visual acuity testing, visual field testing, and imaging studies such as MRI or CT scans to evaluate the brain. Treatment options for hemianopsia depend on the underlying cause and may include:

1. Glasses or contact lenses to correct refractive errors.
2. Prism lenses to realign the visual image.
3. Visual therapy to improve remaining vision.
4. Medications to treat underlying conditions such as multiple sclerosis or brain tumors.
5. Surgery to repair damaged blood vessels or relieve pressure on the brain.

It is important to note that hemianopsia can significantly impact daily life and may affect an individual's ability to perform certain tasks, such as driving or reading. However, with proper diagnosis and treatment, many people with hemianopsia are able to adapt and lead fulfilling lives.

There are several types of strabismus, including:

* Esotropia: where one eye turns inward toward the nose
* Exotropia: where one eye turns outward away from the face
* Hypertropia: where one eye turns upward
* Hypotropia: where one eye turns downward
* Duane's syndrome: a rare type of strabismus that affects only one eye and is caused by nerve damage.

Strabismus can have both visual and social consequences, including:

* Difficulty with depth perception and binocular vision
* Blurred or double vision
* Difficulty with eye teaming and tracking
* Poor eye-hand coordination
* Social and emotional effects such as low self-esteem, anxiety, and depression.

Treatment options for strabismus include:

* Glasses or contact lenses to correct refractive errors
* Prism lenses to align the eyes
* Eye exercises to strengthen the muscles and improve eye teaming
* Surgery to adjust the position of the muscles that control eye movement.

It is important for individuals with strabismus to receive timely and appropriate treatment to address the underlying cause of the condition and prevent long-term vision loss and social difficulties.

Characteristics: People with cortical blindness may have difficulty recognizing objects, navigating their environment, and perceiving light and colors. They may also experience visual hallucinations or distortions. The blindness can be partial or total, and the degree of vision loss can vary widely.

Causes: Cortical blindness can be caused by a variety of factors, including:

* Stroke or brain injury that damages the visual cortex
* Infections such as meningitis or encephalitis that affect the visual cortex
* Genetic disorders such as retinitis pigmentosa or Leber's congenital amaurosis
* Traumatic brain injury
* Tumors or cysts in the visual cortex

Symptoms: Symptoms of cortical blindness can include:

* Difficulty recognizing objects or faces
* Poor spatial awareness and navigation
* Blurred or distorted vision
* Sensitivity to light or glare
* Visual hallucinations or distortions
* Partial or total loss of vision

Diagnosis: Diagnosis of cortical blindness typically involves a comprehensive eye exam, neurological evaluation, and imaging tests such as MRI or CT scans to identify any underlying causes.

Treatment: There is no cure for cortical blindness, but various therapies and strategies can help improve functional vision and independence. These may include:

* Vision rehabilitation therapy to improve visual function and adapt to new ways of seeing
* Assistive technology such as telescopes or closed-circuit television systems to enhance remaining vision
* Training in mobility and orientation skills
* Compensatory strategies for daily activities

Prognosis: The prognosis for cortical blindness varies depending on the underlying cause and severity of the condition. In some cases, partial recovery of vision may be possible with time and therapy, while in other instances, visual function may remain impaired or stable.

Prevention: Prevention of cortical blindness is not always possible, but early detection and treatment of underlying conditions can help reduce the risk of vision loss. Regular eye exams and monitoring by a neurologist or ophthalmologist can also help identify any changes in vision and potential causes of cortical blindness.

Overall, cortical blindness is a complex and rare condition that requires specialized care and rehabilitation to improve functional vision and independence. With the right therapies and strategies, individuals with cortical blindness can lead fulfilling lives and adapt to their new visual reality.

Some common types of perceptual disorders include:

1. Visual perceptual disorders: These disorders affect an individual's ability to interpret and make sense of visual information from the environment. They can result in difficulties with recognizing objects, perceiving depth and distance, and tracking movement.
2. Auditory perceptual disorders: These disorders affect an individual's ability to interpret and make sense of sound. They can result in difficulties with hearing and understanding speech, as well as distinguishing between different sounds.
3. Tactile perceptual disorders: These disorders affect an individual's ability to interpret and make sense of touch. They can result in difficulties with recognizing objects through touch, as well as interpreting tactile sensations such as pain, temperature, and texture.
4. Olfactory perceptual disorders: These disorders affect an individual's ability to interpret and make sense of smells. They can result in difficulties with identifying different odors and distinguishing between them.
5. Gustatory perceptual disorders: These disorders affect an individual's ability to interpret and make sense of tastes. They can result in difficulties with identifying different flavors and distinguishing between them.
6. Balance and equilibrium disorders: These disorders affect an individual's ability to maintain balance and equilibrium. They can result in difficulties with standing, walking, and maintaining posture.

Perceptual disorders can have a significant impact on an individual's daily life, making it difficult to perform everyday tasks and activities. Treatment for perceptual disorders often involves a combination of sensory therapy, behavioral therapy, and assistive technologies. The goal of treatment is to help the individual compensate for any impairments in sensory processing and improve their ability to function in daily life.

There are several subtypes of agnosia, each with distinct symptoms:

1. Visual agnosia: Difficulty recognizing objects, colors, or shapes.
2. Auditory agnosia: Inability to recognize familiar sounds or voices.
3. Tactile agnosia: Difficulty identifying objects by touch.
4. Olfactory agnosia: Loss of the ability to smell.
5. Gustatory agnosia: Inability to taste or identify different flavors.
6. Hyperagnosia: Excessive sensitivity to stimuli, leading to over-recognition of objects and excessive memory for details.
7. Hypoagnosia: Under-recognition of objects, leading to difficulty identifying familiar items.

Agnosia can be caused by various factors, such as stroke, traumatic brain injury, infections, neurodegenerative diseases (e.g., Alzheimer's disease, Parkinson's disease), and developmental disorders (e.g., autism spectrum disorder). Treatment options depend on the underlying cause of the agnosia and may include rehabilitation therapies, medications, or surgery.

In summary, agnosia is a neurological condition characterized by difficulty in recognizing objects, voices, or other sensory stimuli due to damage to specific areas of the brain. It can affect one or more senses and can be caused by various factors. Treatment options vary depending on the underlying cause of the disorder.

The most common symptoms of albinism include:

* Pale or white skin, hair, and eyes
* Sensitivity to the sun and risk of sunburn
* Poor vision, including nystagmus (involuntary eye movements) and photophobia (sensitivity to light)
* Increased risk of eye problems, such as strabismus (crossed eyes) and amblyopia (lazy eye)
* Increased risk of skin cancer and other skin problems
* Delayed development of motor skills and coordination
* Increased risk of infection and other health problems due to a weakened immune system

Albinism is caused by mutations in genes that code for enzymes involved in the production of melanin. These mutations can be inherited from one or both parents, or they can occur spontaneously. There is no cure for albinism, but there are treatments available to help manage some of the associated symptoms and vision problems.

Diagnosis of albinism is typically made based on a combination of physical examination, medical history, and genetic testing. Treatment may include sun protection measures, glasses or contact lenses to improve vision, and medication to manage eye problems. In some cases, surgery may be necessary to correct eye alignment or other physical abnormalities.

It's important for people with albinism to receive regular medical care and monitoring to ensure early detection and treatment of any associated health problems. With proper care and support, many people with albinism can lead normal, fulfilling lives.

Low vision is not the same as blindness, but it does affect an individual's ability to perform daily activities such as reading, driving, and recognizing faces. The condition can be treated with low vision aids such as specialized glasses, telescopes, and video magnifiers that enhance visual acuity and improve the ability to see objects and details more clearly.

In the medical field, Low Vision is often used interchangeably with the term "visual impairment" which refers to any degree of vision loss that cannot be corrected by regular glasses or contact lenses. Visual impairment can range from mild to severe and can have a significant impact on an individual's quality of life.

Low Vision is a common condition among older adults, with approximately 20% of people over the age of 65 experiencing some degree of visual impairment. However, Low Vision can also affect younger individuals, particularly those with certain eye conditions such as retinitis pigmentosa or other inherited eye disorders.

Overall, Low Vision is a condition that affects an individual's ability to see clearly and perform daily activities, and it is important for individuals experiencing vision loss to seek medical attention to determine the cause of their symptoms and explore available treatment options.

Visual area V2, or secondary visual cortex, also called prestriate cortex, is the second major area in the visual cortex, and ... the visual cortex in the left hemisphere receives signals from the right visual field, and the visual cortex in the right ... Visual area V4 is one of the visual areas in the extrastriate visual cortex. In macaques, it is located anterior to V2 and ... The visual cortex of the brain is the area of the cerebral cortex that processes visual information. It is located in the ...

https://en.wikipedia.org/wiki/Visual_cortex

The extrastriate cortex is the region of the occipital cortex of the mammalian brain located next to the primary visual cortex ... In primates, the extrastriate cortex includes visual area V3, visual area V4, and visual area MT (sometimes called V5), while ... Primary visual cortex (V1) is also named striate cortex because of its striped appearance in the microscope. The extrastriate ... Higher Order Visual Processing in Macaque Extrastriate Cortex. Physiol Rev January 1, 2008 88:(1) 59-89; doi:10.1152/physrev. ...

https://en.wikipedia.org/wiki/Extrastriate_cortex

Cortical areas have specific functions such as movement in the motor cortex, and sight in the visual cortex. Visual cortex is ... and the right visual cortex receives information from the left visual field. The organization of sensory maps in the cortex ... "The primary visual cortex", Webvision: Comprehensive article about the structure and function of the primary visual cortex. " ... and touch are served by the primary visual cortex, primary auditory cortex and primary somatosensory cortex respectively. In ...

https://en.wikipedia.org/wiki/Cerebral_cortex

"A computational model for the development of multiple maps in primary visual cortex". Cerebral Cortex. 15 (8): 1222-1233. doi: ... All three types of column are present in the visual cortex of humans and macaques, among other animals. In macaques, it was ... Shatz, C. J.; Stryker, M. P. (1978). "Ocular dominance in layer IV of the cat's visual cortex and the effects of monocular ... Crair, M. C.; Horton, J. C.; Antonini, A.; Stryker, M. P. (2001). "Emergence of Ocular Dominance Columns in Cat Visual Cortex ...

https://en.wikipedia.org/wiki/Ocular_dominance_column

Area 17 of the visual cortex was found to contain about 51,400 neurons per mm3. Area 17 is the primary visual cortex. Feline ... Payne, B. R.; Siwek, D. F. (1991). "The Visual Map in the Corpus Callosum of the Cat". Cerebral Cortex. 1 (2): 173-88. doi: ... "visual cortex". Farlex. Retrieved 22 May 2016. "Gyrencephalic Definition". Serendip. Archived from the original on 3 June 2012 ... Sturman JA, Lu P, Xu Y, Imaki H (1994). "Feline maternal taurine deficiency: Effects on visual cortex of the offspring. A ...

https://en.wikipedia.org/wiki/Cat_intelligence

The extrastriate body area (EBA) is a subpart of the extrastriate visual cortex involved in the visual perception of human body ... The Visual Cortex category measures the response of the FFA to be used as the control of the experiment. This measurement of ... The data from the Sham and Visual Cortex categories on the graph show what was the expected normal results from the experiment ... What the experiment found was a specific area of the lateral occipitotemporal cortex that responds selectively to visual images ...

https://en.wikipedia.org/wiki/Extrastriate_body_area

... and process visual information relayed from the retinas. The visual cortex, located in the occipital lobe, handles this process ... For instance, the spatial distribution of network modules in auditory and visual cortex and of hub-like areas became more ... Huff T, Mahabadi N, Tadi P (2022). "Neuroanatomy, Visual Cortex". StatPearls. Treasure Island (FL): StatPearls Publishing. PMID ... Yang YL, Deng HX, Xing GY, Xia XL, Li HF (February 2015). "Brain functional network connectivity based on a visual task: visual ...

https://en.wikipedia.org/wiki/Network_neuroscience

Visual processing of the occluded stimulus begins in the primary visual cortex (V1), in the occipital lobe of the brain. V1 ... This is important in the visual system to aid in de-cluttering our visual environment, and interpreting information at a faster ... I-Perception, 9(4), 1-16 Lee, H., & Vecera, S. P. (2005). Visual cognition influences early vision: the role of visual short- ... It is one of the many functions of the visual system which aid in both seeing and understanding objects encountered on an ...

https://en.wikipedia.org/wiki/Amodal_completion

The visual cortex located in the occipital lobe of the brain is that part of the cerebral cortex which processes visual ... Cortical blindness refers to any partial or complete visual deficit that is caused by damage to the visual cortex in the ... Lesions in that pathway cause a variety of visual field defects. In the visual system of human eye, the visual information ... Visual system Visual field Visual field test Eye examination AK Khurana (31 August 2015). "Neuro-ophthalmology". Comprehensive ...

https://en.wikipedia.org/wiki/Visual_pathway_lesions

In extreme cases, the tau protein calcarine cortex, which contains the primary visual cortex in the brain. In the study, ... "Primary visual cortex , Radiology Reference Article , Radiopaedia.org". Radiopaedia. Retrieved 2019-03-18. Belson, Ken (2017-09 ... In stage I CTE, p-tau pathology can be observed in the cerebral cortex, most likely in the area between sulci. In the second ... In stage IV CTE, severe p-tau pathology is spread across all areas of the cerebral cortex and temporal lobe. ...

https://en.wikipedia.org/wiki/Boston_University_CTE_Center_and_Brain_Bank

"The Role of Visual Cortex for Binocular Interactions in the Cat Lateral Geniculate Nucleus." The Role of Visual Cortex for ... somatosensory cortex), movement (motor cortex), and vision (visual cortex), was first proposed by Franz Joseph Gall in 1810. ... These secondary visual areas (collectively termed the extrastriate visual cortex) process a wide variety of visual primitives. ... After that, the visual pathway is roughly separated into a ventral and dorsal pathway). The visual cortex is the largest system ...

https://en.wikipedia.org/wiki/Visual_system

... in Macaque Visual Cortex". Cerebral Cortex. 14 (4): 353-363. doi:10.1093/cercor/bhh001. PMID 15028640. Pasupathy, A (2006). " ... Livingstone, MS; Hubel, DH (Jan 1984). "Anatomy and physiology of a color system in the primate visual cortex". The Journal of ... Grill-Spector, K.; Malach, R. (2004). "The Human Visual Cortex". Annual Review of Neuroscience. 27: 649-677. doi:10.1146/ ... Zeki, S. (1 January 1990). "Parallelism and Functional Specialization in Human Visual Cortex". Cold Spring Harbor Symposia on ...

https://en.wikipedia.org/wiki/Visual_modularity

Sonja Hansen (May 9, 2019). "Pokemon triggers visual cortex". Vol. 255, no. 53. The Stanford Daily. p. 1. Chen, Angela (May 6, ... finding that seeing Pokémon stimulated activity in the visual cortex, in a different place than is triggered by recognizing ...

https://en.wikipedia.org/wiki/Pokémon

The OVC was designed to work as a simulated visual cortex that has a critical job in processing and classify the objects to ... "How the Visual Cortex Recognizes". Poggio Lab., the Center for Biological & Computational Learning at the Massachusetts ... Human visual system model Visual system Machine Vision Image processing OpenCV Greenemeier, Larry (2008). "Visionary Research: ... and it's designed to give the researchers to experience the brain's visual cortex most close simulation for picture perception ...

https://en.wikipedia.org/wiki/Objective_vision

Friday, 18 November 2011 Dani CooperABC (2011-11-18). "Synaesthesia sends visual cortex crazy". Retrieved 2020-02-12. ORCID. " ...

https://en.wikipedia.org/wiki/Devin_Terhune

... schema of the visual map theory (1898). O=Optic chiasm; C=Visual (and motor) cortex; M, S=Decussating pathways; R, G: Sensory ... Ramón y Cajal, Santiago (1899). Comparative study of the sensory areas of the human cortex. Clark University. p. 85. Ramón y ... "Comparative study of the sensory areas of the human cortex" ...

https://en.wikipedia.org/wiki/Santiago_Ramón_y_Cajal

13(12): p. 1554-9. Ress, D., B.T. Backus, and D.J. Heeger, Activity in primary visual cortex predicts performance in a visual ... Huk, A.C. and D.J. Heeger, Pattern-motion responses in human visual cortex. Nat Neurosci, 2002. 5(1): p. 72-5. Heeger, D.J., et ... visual awareness, visual pattern detection/discrimination, visual motion perception, stereopsis (depth perception), attention, ... 3(11): p. 1153-9. Lee, S.H., R. Blake, and D.J. Heeger, Traveling waves of activity in primary visual cortex during binocular ...

https://en.wikipedia.org/wiki/David_Heeger

"Synaptology of the visual cortex." Visual Centers in the Brain. Springer Berlin Heidelberg, 1973. 269-324. Kossuth Prize (1950 ... There he mainly addressed the cerebellum and functioning of the cerebral cortex. In addition, he performed experimental ...

https://en.wikipedia.org/wiki/János_Szentágothai

Dikker, S. & Pylkkänen, L. (2011). Before the N400: Effects of lexical-semantic violations in visual cortex. Brain and Language ... Dikker, S., Rabagliati, H. & Pylkkänen, L. (2009). Sensitivity to syntax in visual cortex. Cognition, 110 (3), 293-321. ... The M100 discussed here is the magnetic equivalent of the visual N1 potential-an event-related potential linked to visual ... In the eyetracking visual world paradigm, experimental subjects listen to a sentence while staring at an array of pictures on a ...

https://en.wikipedia.org/wiki/Prediction_in_language_comprehension

In binocular neurons in the visual cortex, it is necessary to specify the corresponding area in both retinas (one in each eye ... In the case of binocular neurons in the visual cortex, receptive fields do not extend to optical infinity. Instead, they are ... Hubel and Wiesel (e.g., Hubel, 1963; Hubel-Wiesel 1959) classified receptive fields of cells in the visual cortex into simple ... It is also described how the receptive fields in the primary visual cortex, which are tuned to different sizes, orientations ...

https://en.wikipedia.org/wiki/Receptive_field

... specific tuning of visual cortex? Functional properties of the Visual Word Form Area". Brain. 125 (5): 1054-1069. doi:10.1093/ ... Cortex. 48 (9): 1234-1249. doi:10.1016/j.cortex.2012.02.010. PMID 22465163. S2CID 8401240. Hurley RS, Paller KA, Rogalski EJ, ... Rapid serial visual presentation (RSVP) reading involves presenting the words in a sentence one word at a time at the same ... Although it is not included in most meta-analytical studies, the sensorimotor cortex of the brain is the most active region of ...

https://en.wikipedia.org/wiki/Reading

"Language-specific tuning of visual cortex? Functional properties of the Visual Word Form Area". Brain. 125 (Pt 5): 1054-1069. ... Signal loss and response bias in visual and frontal cortex". Science. 360 (6388): 537-542. Bibcode:2018Sci...360..537V. doi: ... Dehaene S, Le Clec'H G, Poline JB, Le Bihan D, Cohen L (2002). "The visual word form area: a prelexical representation of ... McCandliss BD, Cohen L, Dehaene S (2003). "The visual word form area: expertise for reading in the fusiform gyrus". Trends in ...

https://en.wikipedia.org/wiki/Stanislas_Dehaene

149-152 MacEvoy, Sean; Michael A. Paradiso (14 March 2001). "Lightness constancy in primary visual cortex". PNAS. 98 (15): 8827 ... There are several types of perceptual constancies in visual perception: Size constancy is one type of visual subjective ... Visual auditory distance constancy - Researchers explored the relationship between visual and auditory responses and how they ... According to Kanwisher & associates, the localized part of the brain responsible for this is the extrastriate cortex. Color ...

https://en.wikipedia.org/wiki/Subjective_constancy

"Dissociation and Convergence of the Dorsal and Ventral Visual Streams in the Human Prefrontal Cortex". NeuroImage. 65: 488-498 ... the posterior parietal cortex, the anterior and posterior cingulate, the premotor cortex, the retrosplenial cortex, and the ... The dorsolateral prefrontal cortex (DLPFC or DL-PFC) is an area in the prefrontal cortex of the primate brain. It is one of the ... Alcohol creates deficits on the function of the prefrontal cortex. As the anterior cingulate cortex works to inhibit any ...

https://en.wikipedia.org/wiki/Dorsolateral_prefrontal_cortex

"Motility of Dendritic Spines in Visual Cortex in Vivo: Changes during the Critical Period and Effects of Visual Deprivation". ... They showed that columns in the primary visual cortex receiving inputs from the other eye took over the areas that would ... However, if one eye is patched, or otherwise prevented from receiving sensory input, the visual cortex will shift to favor ... Early in development, most of the visual cortex is binocular, meaning it receives roughly equal input from both eyes. Normally ...

https://en.wikipedia.org/wiki/Critical_period

Areas of the visual cortex including V2, V3, V3a, V4, all part of visual processing, and MT and MST, which specifically respond ... Behavioral enhancement of visual responses in monkey cerebral cortex: I. Modulation in posterior parietal cortex related to ... Brain areas including the superior colliculus are important for visual processing. The pre-striate area of the visual cortex, ... The bottom-up influence is a saliency signal likely generated by the primary visual cortex (V1) from external sensory inputs, ...

https://en.wikipedia.org/wiki/Mickey_Goldberg

Huk, Alexander C.; Heeger, David J. (2002-01-01). "Pattern-motion responses in human visual cortex". Nature Neuroscience. 5 (1 ... "Neural Activity in Macaque Parietal Cortex Reflects Temporal Integration of Visual Motion Signals during Perceptual Decision ... In his doctoral work, Huk used fMRI to map the human brain areas associated with visual motion processing. His postdoctoral ... He has made contributions towards understanding how the brain represents 3D visual motion and how those representations are ...

https://en.wikipedia.org/wiki/Alexander_Huk

Archived 2007-12-03 at the Wayback Machine Hensch TK (2005). "Critical period mechanisms in developing visual cortex". Neural ...

https://en.wikipedia.org/wiki/Chondroitinase_treatment

Insular cortex Area 17 - Primary visual cortex (V1) Area 18 - Secondary visual cortex (V2) Area 19 - Associative visual cortex ... The primary visual cortex (Brodmann area 17), which is the main recipient of direct input from the visual part of the thalamus ... area 4 is the primary motor cortex; area 17 is the primary visual cortex; and areas 41 and 42 correspond closely to primary ... Brodmann area 17 is the primary visual cortex, and Brodmann area 25 is the anterior cingulate cortex. Many of those brain areas ...

https://en.wikipedia.org/wiki/Brodmann_area

HTM is also related to work by Tomaso Poggio, including an approach for modeling the ventral stream of the visual cortex known ... While HTM is mostly consistent with these ideas, it adds details about handling invariant representations in the visual cortex ... George, Dileep (2010-07-24). "Hierarchical Bayesian inference in the visual cortex". dileepgeorge.com. Archived from the ... "Hierarchical Bayesian Inference in the Visual Cortex". Journal of the Optical Society of America A. 20 (7): 1434-48. CiteSeerX ...

https://en.wikipedia.org/wiki/Hierarchical_temporal_memory

The prefrontal cortex is thought essential for all goal-directed and socially-mediated behavior. The PFC is an ideal target for ... The ratio of red/infrared light refraction is displayed as a visual signal on a computer monitor and may also be translated ... When a region of the cortex is used in a specific cognitive task, neuronal activity in that region increases, consequently ... must increase the amount of oxygen they deliver to the activated region of the cortex, resulting in a greater local blood ...

https://en.wikipedia.org/wiki/Hemoencephalography

... and primary visual cortex (V1) and to the superior colliculus (SC). Ten-m3 facilitates the retinotopic mapping of ipsilateral ... m3 and Bcl6 in Patterning Visual and Somatosensory Pathways". Cerebral Cortex. 18 (1): 53-66. doi:10.1093/cercor/bhm031. PMID ... which encode visual input from the binocular visual field, to the dorsomedial dLGN and to the rostromedial SC. Immunostaining ... Ten-m3 null mutant mice performed worse than wild type (WT) in behavioural tests of binocular visual function, such as vertical ...

https://en.wikipedia.org/wiki/TENM3

Cortisol is secreted by the cortex of the adrenal gland from a region called the zona fasciculata in response to ACTH. Elevated ... Performing a physical examination to determine any visual field defect may be necessary if a pituitary lesion is suspected, ... One of the causes of Cushing's syndrome is a cortisol-secreting adenoma in the cortex of the adrenal gland (primary ... Excessive ACTH stimulates the adrenal cortex to produce high levels of cortisol, producing the disease state. While all ...

https://en.wikipedia.org/wiki/Cushing's_syndrome

See Dario L. Ringach Receptive Fields in Macaque Primary Visual Cortex Spatial Structure and Symmetry of Simple-Cell (2002) J. ... component analysis of natural image sequences yields spatio-temporal filters similar to simple cells in primary visual cortex ( ...

https://en.wikipedia.org/wiki/Spectro-temporal_receptive_field

Die Sehrinde : eine anthropologische Studie an Schweizerhirnen, 1914 - The visual cortex. Anatomie des grosshirns, ...

https://en.wikipedia.org/wiki/Eber_Landau

... primary visual cortex) can detect the existence of disparity in their input from the eyes. Specifically, these neurons will be ... Visual binocular disparity is defined as the difference between the point of projection in the two eyes and is usually ... Brain cells (neurons) in a part of the brain responsible for processing visual information coming from the retinae ( ... binocular disparity is referenced as coordinate differences of the point between the right and left images instead of a visual ...

https://en.wikipedia.org/wiki/Binocular_disparity

van Ede F, Chekroud SR, Nobre AC (2019) Human gaze tracks attentional focusing in memorised visual space. Nature Human ... Face recognition in human extrastriate cortex. Journal of Neurophysiology 71(2):821-5. Nobre AC, Sebestyen GN, Gitelman DR, ... Functional magnetic resonance imaging of human prefrontal cortex activation during a spatial working memory task. Proceedings ...

https://en.wikipedia.org/wiki/Anna_Christina_Nobre

Children with ZTTK syndrome may present with vision problems including optic atrophy and cerebral visual impairment, resulting ... Characteristic abnormalities include cerebral cortex malformations, vision difficulties, musculoskeletal abnormalities and ... in poor visual responses. Strabismus; misalignment or crossing of the eyes when viewing an object, direct hypermetropia; ... from affected individuals with ZTTK syndrome confirmed the downregulation of genes essential for neuronal migration and cortex ...

https://en.wikipedia.org/wiki/ZTTK_syndrome

G. sabrinus is particularly adapted to finding truffles using its refined sense of smell, visual clues, and long-term memory of ... Hyphae then enter the root cortex intercellularly to form the Hartig net for nutrient exchange. Hyphae can spread to other root ...

https://en.wikipedia.org/wiki/Truffle

A stereoscopic rangefinder uses two eyepieces and relies on the operator's visual cortex to merge the two images into a single ...

https://en.wikipedia.org/wiki/Stereoscopic_rangefinder

Motion perception Motion sensing in vision Visual perception Optical illusion Change blindness Visual cortex Suchow, Jordan W ... "Opposite neural signatures of motion-induced blindness in human dorsal and ventral visual cortex". Journal of Neuroscience. 28 ... Do explicit reports underestimate the representation of change in the visual system?". Visual Cognition. 7 (1-3): 324-344. ... Motion silencing stems from the study of change blindness which in essence is the failure to detect change in the visual field ...

https://en.wikipedia.org/wiki/Motion_silencing_illusion

The kinesthetic sensations of the contracting and relaxing ciliary muscles (intraocular muscles) is sent to the visual cortex ... If one subtends a larger visual angle on the retina than the other, the object which subtends the larger visual angle appears ... Depth perception is the ability to perceive distance to objects in the world using the visual system and visual perception. It ... Visual perception of perspective in real space, for instance in rooms, in settlements and in nature, is a result of several ...

https://en.wikipedia.org/wiki/Depth_perception

Nobel Prize winner in medicine for mapping the visual cortex Harold E. Johns OC (1915-1998) - medical physicist, noted for his ...

https://en.wikipedia.org/wiki/Lists_of_Canadians

The processing largely takes place in the visual cortex. Children who are blind miss out on fundamental parts of early and ... In addition, their visual appearance is designed to make them easy to tell apart for persons who cannot read the inscriptions ... Braille is read by people who are blind, deafblind or who have low vision, and by both those born with a visual impairment and ... Since Braille is one of the few writing systems where tactile perception is used, as opposed to visual perception, a braille ...

https://en.wikipedia.org/wiki/Braille

... extends to the inferior parietal cortex and ends with the posterior and inferior frontal cortexes, specifically in Broca's area ... Auditory and visual analysis has established that the vocal tract has developed a coarticulation of consonants and vowels ... The study concludes that the combination of audio and visual stimuli have little effect on a driver's ability to manoeuvre a ... This research concluded that concentration on a visual stimuli draws the attention of the auditory system to the same direction ...

https://en.wikipedia.org/wiki/Speech_shadowing

The ARTPEC-8 SoC released in 2021, is powered by an ARM Cortex-A53 CPU. The SoC is similar to its predecessor using the same ... In 2022, the company released its first Network Strobe Siren which provides audible and visual alerts. Radar - In 2017, Axis ... The ARTPEC-6 SoC released in 2016, is powered by an ARM Cortex-A9 CPU. The image processing pipeline is based on ETRAX CRIS. ... The ARTPEC-7 SoC released in 2019, is powered by an ARM Cortex-A9 CPU. The image processing pipeline is based on ETRAX CRIS. ...

https://en.wikipedia.org/wiki/Axis_Communications

However, once those objectNEs are time-shifted by the lateral prefrontal cortex (LPFC) to fire in-phase with each other, they ... Finke, Ronald A.; Slayton, Karen (May 1988). "Explorations of creative visual synthesis in mental imagery". Memory & Cognition ... Unlike dreaming, which is spontaneous and not controlled by the prefrontal cortex (PFC), PFS is controlled by and completely ... Christoff, Kalina; Gabrieli, John D. E. (4 November 2013). "The frontopolar cortex and human cognition: Evidence for a ...

https://en.wikipedia.org/wiki/Prefrontal_synthesis

All mGluRs except mGluR6 are thought to exist in the hippocampus and entorhinal cortex. It is thought that mGluRs play a role ... "Presynaptic inhibitory action of metabotropic glutamate receptor agonist on excitatory transmission in visual cortical neurons ... They are found in pre- and postsynaptic neurons in synapses of the hippocampus, cerebellum, and the cerebral cortex, as well as ... Receptors in groups II and III reduce the activity of postsynaptic potentials, both excitatory and inhibitory, in the cortex. ...

https://en.wikipedia.org/wiki/Metabotropic_glutamate_receptor

The basis of this work takes place in the visual cortex of the brain. The visual cortex is located in the occipital lobe of the ... The primary visual cortex is located within the occipital lobe in the back of infant's brain and is responsible for processing ... Within the primary visual cortex, there are four pathways: the superior colliculus pathway (SC pathway), the middle temporal ... visual demonstration, visual stimulation (electronic), visual stimulation (just pictures), games, social interaction, and ...

https://en.wikipedia.org/wiki/Visual_learning

Visual misperceptions or illusions are also common in DLB but differ from visual hallucinations. While visual hallucinations ... Areas of the brain and functions affected: cerebral cortex - thought, perception and language; limbic cortex - emotions and ... Examples of visual hallucinations "vary from 'little people' who casually walk around the house, 'ghosts' of dead parents who ... Depression, apathy, and visual hallucinations contribute to the reduced quality of life. Decline may be more rapid when the ...

https://en.wikipedia.org/wiki/Dementia_with_Lewy_bodies

Best Story Telling and Best Visual Design. In 2018, GamesRadar ranked the game 8th in their list of "the 20 best horror games ... they argue about the nature of their mission until Catherine's cortex chip short-circuits from overexertion, effectively ...

https://en.wikipedia.org/wiki/Soma_(video_game)

The structure in layer I and II is somewhat similar to the cerebral cortex if stellate cells are assumed to be involved in ... Capsnets explore the intuition that the human visual system creates a tree-like structure for each focal point and coordinates ... Capsnets build on inspirations from cortical minicolumns (also called cortical microcolumns) in the cerebral cortex. A ... spanning all layers in the cerebral cortex. All neurons in the larger minicolumns have the same receptive field, and they ...

https://en.wikipedia.org/wiki/Capsule_neural_network

Cortical grey matter development peaks at ~12 years of age in the frontal and parietal cortices, and 14-16 years in the ... Dunlop, S. A.; Tee, L. B.; Lund, R. D.; Beazley, L. D. (1997). "Development of primary visual projections occurs entirely ... Robinson, S. R.; Dreher, B (1990). "The visual pathways of eutherian mammals and marsupials develop according to a common ... most notably in the frontal and parietal cortices. ... temporal lobes (with the superior temporal cortex being last to ...

https://en.wikipedia.org/wiki/Human_brain_development_timeline

"Direction selectivity of synaptic potentials in simple cells of the cat visual cortex". Journal of Neurophysiology. 78 (5): ... Interactive Reichardt Detector Video demonstrating second-order motion perception Visual Motion Analysis Visual Neuroscience, ... the visual system must integrate those individual local motion signals at various parts of the visual field into a 2- ... In monocular vision for example, the visual input will be a 2D projection of a 3D scene. The motion cues present in the 2D ...

https://en.wikipedia.org/wiki/Motion_perception

"High-dimensional geometry of population responses in visual cortex". Nature. 571 (7765): 361-365. doi:10.1038/s41586-019-1346-5 ...

https://en.wikipedia.org/wiki/Kenneth_D_Harris

... s do, however, lack short wavelength sensitive visual pigments in their cone cells indicating a more limited capacity for ... Hof, Patrick R.; Van Der Gucht, Estel (2007). "Structure of the cerebral cortex of the humpback whale, Megaptera novaeangliae ( ...

https://en.wikipedia.org/wiki/Whale

The visual ability of an echidna is not great, and it is not known whether it can perceive colour; however, it can distinguish ... The cerebral cortex is thinner, and the brain cells are larger and more densely packed and organised in the echidna than the ... The short-beaked echidna has the largest prefrontal cortex relative to body size of any mammal, taking up 50% of the volume in ... A highly sensitive optic nerve has been shown to have visual discrimination and spatial memory comparable to those of a rat. ...

https://en.wikipedia.org/wiki/Short-beaked_echidna

Higher level visual regions, such as the fusiform gyrus, extrastriate cortex and superior temporal sulcus (STS) are the areas ... The orbitofrontal cortex being important in the processing of social cues leads researchers to believe that it works with the ... When it comes to visual cues, individuals follow the gaze of others to find out what they are looking at. It has been found ... When people focus on things in a social context, the medial prefrontal cortex and precuneus areas of the brain are activated, ...

https://en.wikipedia.org/wiki/Social_cue

... whilst your ability to recognize and imagine the visual features of a dog resides in your visual cortex. Recent evidence ... temporal cortex, parietal cortex (size knowledge), and premotor cortex (manipulation knowledge). Other areas, such as more ... and the perirhinal cortex. These latter two make up the "parahippocampal cortices". Amnesics with damage to the hippocampus but ... the left lateral temporal cortex in knowledge of motion, and the parietal cortex in knowledge of size. Neuroimaging studies ...

https://en.wikipedia.org/wiki/Semantic_memory

Cortex. 77: 1-12. doi:10.1016/j.cortex.2016.01.002. PMC 5357080. PMID 26889603. Jones, Simon R.; Fernyhough, Charles (2007). " ... If this is done, one notices that the visual world seems to have "moved" as a result of this passive movement of the eyeball. ... Herdman, SJ; Schubert MC; Tusa RJ (2001). "Role of Central Preprogramming in Dynamic Visual Acuity With Vestibular Loss". Arch ... Gyr John W (1972). "Is a Theory of Direct Visual Perception Adequate?". Psychological Bulletin. 77 (4): 246-261 [250]. doi: ...

https://en.wikipedia.org/wiki/Efference_copy

... Cereb Cortex. 2016 Mar;26(3):991-1003. doi: ... We characterized the functional excitatory local input to these 3 cell subtypes in rat primary visual cortex using laser- ...

https://pubmed.ncbi.nlm.nih.gov/25405939/

Vice Provost for Research and William Ziegler III Professor of Neuroscience and Professor of Ophthalmology and Visual Science; ...

https://medicine.yale.edu/research-profiles/?orgId=113592&meshId=14177

The Güdform 32 channel MR coil is atlas-optimised for visual cortex imaging and provides 7T-like performance on standard 3T ... high-resolution imaging of the visual cortex, down to 0.75mm isotropic voxel resolution for fMRI, and 0.35mm isotropic ...

https://www.crsltd.com/tools-for-functional-imaging/mr-coils/visual-cortex-phased-array-mri-coil/nest/spgr-flash-image

A two-photon imaging tale: integration and specialization in mouse visual cortex. 2012, University of Zurich, Faculty of ... A two-photon imaging tale: integration and specialization in mouse visual cortex ...

https://www.zora.uzh.ch/id/eprint/75443/

Author(s): Hensch, Takao Kurt | Abstract:

https://escholarship.org/uc/item/228468h9

Unconscious and Conscious Processing of Color Rely on Activity in Early Visual Cortex: A TMS Study In Special Collection: ... Unconscious Priming Requires Early Visual Cortex at Specific Temporal Phases of Processing J Cogn Neurosci (September,2013) ... In this study, the contribution of early visual cortex activity to conscious and unconscious chromatic processing was studied ... Unconscious and Conscious Processing of Color Rely on Activity in Early Visual Cortex: A TMS Study. J Cogn Neurosci 2012; 24 (4 ...

https://direct.mit.edu/jocn/article-abstract/24/4/819/27743/Unconscious-and-Conscious-Processing-of-Color-Rely?redirectedFrom=fulltext

... Part of Advances in Neural Information ... Here we analyze the emergence of such complex response patterns in a simple model of primary vi(cid:173) sual cortex. We show ...

https://papers.nips.cc/paper/1996/hash/fe51510c80bfd6e5d78a164cd5b1f688-Abstract.html

Temporary Visual Deprivation Causes Decorrelation of Spatiotemporal Population Responses in Adult Mouse Auditory Cortex. ... Temporary Visual Deprivation Causes Decorrelation of Spatiotemporal Population Responses in Adult Mouse Auditory Cortex ... Temporary Visual Deprivation Causes Decorrelation of Spatiotemporal Population Responses in Adult Mouse Auditory Cortex ... Temporary Visual Deprivation Causes Decorrelation of Spatiotemporal Population Responses in Adult Mouse Auditory Cortex ...

https://www.eneuro.org/content/6/6/ENEURO.0269-19.2019/tab-article-info

Here, we identified individual factors contributing to cross-modal effects on visual cortex excitability and studied the ... Preperceptual and stimulus-selective enhancement of low-level human visual cortex excitability by sounds. Current Biology, 19, ... the impact of different L-sound velocities on phosphene perception postsound as a function of individual auditory versus visual ... have been shown to selectively increase visual cortex excitability [Romei, V., Murray, M. M., Cappe, C., & Thut, G. ...

https://serval.unil.ch/fr/notice/serval:BIB_AB44E55DB063

Dive into the research topics of Orientation-tuned fMRI adaptation in human visual cortex. Together they form a unique ...

https://experts.umn.edu/en/publications/orientation-tuned-fmri-adaptation-in-human-visual-cortex/fingerprints/?sortBy=alphabetically

Visual Cortex; Visual Pathways; Humans; Magnetic Resonance Imaging; Brain Mapping; Photic Stimulation; Pattern Recognition, ... V2 and later visual areas are sensitive to these features, while primary visual cortex is not (Freeman et al., 2013). Here we ... Visual; Visual Perception; Adolescent; Adult; Middle Aged; Female; Male; Young Adult. Subjects:. R Medicine , RC Internal ... Our results highlight structural regularity as an important stimulus dimension for distinguishing the early stages of visual ...

https://repository.essex.ac.uk/18796/

VISUAL CORTEX ...

https://visualcortex.wirediq.com/password_resets/new

Visual Hallucinations and the Curious Absence of Activity in the Primary Visual Cortex February 27, 2023 ... Clusters in visual cortex. by Frans Cornelissen , posted in: New Paper , 0 ... based on measuring the phase relationships between the responses in the visual cortex - reveals similar functional clusters ... during both resting-state and visual field mapping fMRI experiments. This is important information, as resting-state activity ...

http://www.visualneuroscience.nl/phase-synchronization-based-parcellation-of-resting-state-fmri-signals-reveals-topographically-organized-clusters-in-early-visual-cortex/

... Dates:. 2 April 2014. ... This talk will be of interest to people interested in ageing, disease or the primate visual system. ...

https://events.manchester.ac.uk/event/event:fwa-htgy973m-me7qro/comparison-of-fmri-measurements-in-lgn-and-primary-visual-cortex-with-visual-deficits-in-glaucoma

Title: Conformal models for hypercolumns and the visual V1 cortex. Authors: Dmitri V. Alekseevsky, Andrea F. Spiro ... The second part presents a model for the hypercolumns, which originates from the symplectic model of the primary visual cortex ... leading problems concerning the applications of differential geometry in studies on the functional architecture of the visual ...

http://arxiv-export-lb.library.cornell.edu/abs/2202.10157

... Part of Advances in Neural Information ... Almost all models of orientation and direction selectivity in visual cortex are based on feedforward connection schemes, where ... Properties of visual cortical neurons are compared in detail to this model and to a classical model of direction selectivity ... insights gained are the possibility that hysteresis underlies visual cortical function, paralleling proposals for short-term ...

https://papers.neurips.cc/paper_files/paper/1994/hash/a64c94baaf368e1840a1324e839230de-Abstract.html

Coherent encoding of subjective spatial position in visual cortex and hippocampus. 10 September 2018 ... Visual odometry of Rhinecanthus aculeatus depends on the visual density of the environment. 01 October 2022 ... S8). Visual landmarks were marked on the walls of the foam sheets under the water level. A circular arena with a radius of 0.34 ... Alexander, A. S. et al. Egocentric boundary vector tuning of the retrosplenial cortex. Sci. Adv. 6, eaaz2322 (2020). ...

https://www.nature.com/articles/s41598-020-71217-1?error=cookies_not_supported&code=24198519-0a5e-4518-b469-de094ed8644d

"Cortical recycling in high-level visual cortex during childhood development",. abstract = "Human ventral temporal cortex ... Cortical recycling in high-level visual cortex during childhood development. Marisa Nordt, Jesse Gomez, Vaidehi S. Natu, Alex A ... Cortical recycling in high-level visual cortex during childhood development. / Nordt, Marisa; Gomez, Jesse; Natu, Vaidehi S. et ... Cortical recycling in high-level visual cortex during childhood development. In: Nature Human Behaviour. 2021 ; Vol. 5, No. 12 ...

https://collaborate.princeton.edu/en/publications/cortical-recycling-in-high-level-visual-cortex-during-childhood-d

Effect of immersive virtual mirror visual feedback on Mu suppression and coherence in motor and parietal cortex in stroke. ... We investigated the activation pattern of the motor cortex (M1) and parietal cortex during immersive virtual reality (VR)-based ... Mu suppression in bilateral M1 and parietal cortex and mu coherence were analyzed. In patients with stroke, MVF induced ... Effect of immersive virtual mirror visual feedback on Mu suppression and coherence in moto ...

https://pesquisa.bvsalud.org/portal/resource/pt/mdl-37532803

Uncorrelated neural firing in mouse visual cortex during spontaneous retinal waves Academic Article * Overview. authors * ...

https://expert.gwu.edu/display/doc-a1339720638b8d71ea19771f1c3d0532

Re-imagining discovery and access to research: grants, datasets, publications, citations, clinical trials, patents and policy documents in one place.

https://app.dimensions.ai/details/publication/pub.1124595764

Here, we investigated how delay-period activity in frontal and parietal cortex, which is known to correlate with the decline in ... explained the most variance in delay-period activity in lateral occipital cortex. These results are consistent with a model of ... of general frontoparietal mechanisms in response to diffusive noise and of stimulus-specific biases in occipital cortex. ...

https://www.timbuschman.com/Publications/Delay-period-activity-in-frontal%2C-parietal%2C-and-occipital-cortex-tracks-noise-and-biases-in-visual-working-memory

We reproduced neural representations found in biological visual systems by simulating their neural resource constraints in a ... A Unified Theory of Early Visual Representations from Retina to Cortex through Anatomically Constrained Deep CNNs. ... The vertebrate visual system is hierarchically organized to process visual information in successive stages. Neural ... whereas in the primary visual cortex (V1), typical RFs are sharply tuned to a precise orientation. There is currently no ...

https://openreview.net/forum?id=S1xq3oR5tQ

The connectivity principles underlying the emergence of orientation selectivity in the primary visual cortex (V1) of mammals ...

https://elsc.huji.ac.il/events-and-outreach/elsc-seminars/elsc-seminars-series/theory-of-feature-selectivity-in-rodent-primary-visual-cortex/

The formation of hierarchical decisions in the visual cortex.. *Roelfsema, P. R. (Keynote speaker) ...

https://pure.knaw.nl/portal/en/activities/the-formation-of-hierarchical-decisions-in-the-visual-cortex

While the temporal variability of the BOLD signal at human visual cortex has been found in the range of a few hundreds of ... While the temporal variability of the BOLD signal at human visual cortex has been found in the range of a few hundreds of ... While the temporal variability of the BOLD signal at human visual cortex has been found in the range of a few hundreds of ... While the temporal variability of the BOLD signal at human visual cortex has been found in the range of a few hundreds of ...

https://hub.tmu.edu.tw/en/publications/relative-latency-and-temporal-variability-of-hemodynamic-response

Visual training with musical notes changes late but not early electrophysiological responses in the visual cortex. In: Journal ... Visual training with musical notes changes late but not early electrophysiological responses in the visual cortex. Journal of ... Visual training with musical notes changes late but not early electrophysiological responses in the visual cortex. / WONG, Alan ... title = "Visual training with musical notes changes late but not early electrophysiological responses in the visual cortex", ...

https://scholars.ln.edu.hk/en/publications/visual-training-with-musical-notes-changes-late-but-not-early-ele

Structure and function relationships during ocular dominance plasticity in the visual cortex.. ... Structure and function relationships during ocular dominance plasticity in the visual cortex.. ...

https://nin.nl/publications/structure-and-function-relationships-during-ocular-dominance-plasticity-in-the-visual-cortex/

... primary somatosensory cortex STC, superior temporal cortex; VFC, ventral frontal cortex; V1, primary visual cortex. Details of ... superior temporal cortex; ITC, inferior temporal cortex; VFC, ventral frontal cortex; V1, primary visual cortex. ... A1, Primary auditory cortex; DFC, dorsolateral frontal cortex; IPC, inferior parietal cortex; ITC, inferior temporal cortex; ... dorsolateral frontal cortex; IPC, inferior parietal cortex; ITC, inferior temporal cortex; MFC, medial frontal cortex; M1C, ...

https://www.jneurosci.org/content/42/18/3749

We characterized the functional excitatory local input to these 3 cell subtypes in rat primary visual cortex using laser-scanning photostimulation. (nih.gov)
V2 and later visual areas are sensitive to these features, while primary visual cortex is not (Freeman et al. (essex.ac.uk)
The second part presents a model for the hypercolumns, which originates from the symplectic model of the primary visual cortex by A. Sarti, G. Citti and J. Petitot, the spherical model of hypercolumns by P. Bressloff and J. Cowan and basic results of the conformal geometry of sphere. (cornell.edu)
The majority of neurons in primary visual cortex are tuned for stimulus orientation, but the factors that account for the range of orientation selectivities exhibited by cortical neurons remain unclear. (maxplanckneuroscience.org)

striate cortex. (nih.gov)

Effect of immersive virtual mirror visual feedback on Mu suppression and coherence in motor and parietal cortex in stroke. (bvsalud.org)
We investigated the activation pattern of the motor cortex (M1) and parietal cortex during immersive virtual reality (VR)-based mirror visual feedback (MVF) of the upper limb in 14 patients with chronic stroke and severe upper limb hemiparesis and in 21 healthy controls. (bvsalud.org)
Mu suppression in bilateral M1 and parietal cortex and mu coherence were analyzed. (bvsalud.org)
The ipsilesional mu coherence between the M1 and parietal cortex in patients with stroke was stronger than controls, regardless of MVF condition (p patients with stroke (p = 0.032). (bvsalud.org)
Here, we investigated how delay-period activity in frontal and parietal cortex, which is known to correlate with the decline in behavioral memory precision observed with increasing memory load, might relate to diffusion and drift. (timbuschman.com)

VEHSS identifies the annual prevalence of diagnosed Disorders of the Optic Nerve and Visual Pathways based on the presence of International Classification of Diseases (ICD)-9 and ICD-10 codes in patient claims or electronic health record (EHR) systems. (cdc.gov)
Diagnosed disorders of the optic nerve and visual pathways include a patient having one or more diagnosis codes indicating one or more of the subgroups listed below. (cdc.gov)
Disorders of the visual pathway and visual cortex include diagnosis codes indicating disorders of visual pathways and visual cortex. (cdc.gov)
Area of the OCCIPITAL LOBE concerned with the processing of visual information relayed via VISUAL PATHWAYS. (bvsalud.org)

In many locations, the SNR of this posterior-only coil is more than 2X greater than a typical vendor-provided whole-head 32 channel coil, and allows for fast, high-resolution imaging of the visual cortex, down to 0.75mm isotropic voxel resolution for fMRI, and 0.35mm isotropic resolution for anatomical imaging. (crsltd.com)
They find that a new method to analyse brain function - based on measuring the phase relationships between the responses in the visual cortex - reveals similar functional clusters during both resting-state and visual field mapping fMRI experiments. (visualneuroscience.nl)

Previously, these changes have only been conceptualized as excitatory gain increases in sensory cortices for acquired fear-relevant stimuli during associative learning. (unboundmedicine.com)
The results of opposing CS+ and CS- modulations in sensory cortex reflect predictions of the Rescorla-Wagner model and current neurobiological findings. (unboundmedicine.com)
The contributions of sensory dominance and attentional bias to cross-modal enhancement of visual cortex excitability. (unil.ch)

Almost all models of orientation and direction selectivity in visual cortex are based on feedforward connection schemes, where genicu(cid:173) late input provides all excitation to both pyramidal and inhibitory neurons. (neurips.cc)
Properties of visual cortical neurons are compared in detail to this model and to a classical model of direction selectivity that does not include excitatory corti co-cortical connections. (neurips.cc)
To address this issue, we used in vivo two-photon calcium imaging to characterize the orientation tuning and spatial arrangement of synaptic inputs to the dendritic spines of individual pyramidal neurons in layer 2/3 of ferret visual cortex. (maxplanckneuroscience.org)

1998. Inhibition of long-term potentiation in developing rat visual cortex but not hippocampus by in utero exposure to polychlorinated biphenyls. (cdc.gov)

insights gained are the possibility that hysteresis underlies visual cortical function, paralleling proposals for short-term memory, and strong limitations on linearity tests that use gratings. (neurips.cc)

TY - JOUR T1 - Conditioned inhibitory and excitatory gain modulations of visual cortex in fear conditioning: Effects of analysis strategies of magnetocortical responses. (unboundmedicine.com)
Swallowing occurs when descending excitatory and inhibitory signals from the cortex and subcortex and ascending signals from the oropharyngeal area trigger the central pattern generator in the bulbar reticular formation ( 5 ). (cdc.gov)

In this study, the contribution of early visual cortex activity to conscious and unconscious chromatic processing was studied using single-pulse TMS in three time windows 40-100 msec after stimulus onset in three conditions: conscious color recognition, forced-choice discrimination of consciously invisible color, and unconscious color priming. (mit.edu)
We found that conscious perception and both measures of unconscious processing of chromatic information depended on activity in early visual cortex 70-100 msec after stimulus presentation. (mit.edu)
Our results highlight structural regularity as an important stimulus dimension for distinguishing the early stages of visual processing, and suggest a previously unrecognized role for V3 in the visual form-processing hierarchy. (essex.ac.uk)
These results are consistent with a model of the differential recruitment of general frontoparietal mechanisms in response to diffusive noise and of stimulus-specific biases in occipital cortex. (timbuschman.com)

Critically, as a child develops, increases in face and word selectivity are directly linked to decreases in limb selectivity, revealing that during childhood, limb selectivity in ventral temporal cortex is repurposed into word and face selectivity. (princeton.edu)

Human ventral temporal cortex contains category-selective regions that respond preferentially to ecologically relevant categories such as faces, bodies, places and words and that are causally involved in the perception of these categories. (princeton.edu)
We discovered that, from young childhood to the teens, face- and word-selective regions in ventral temporal cortex expand and become more category selective, but limb-selective regions shrink and lose their preference for limbs. (princeton.edu)

In comparison, a subsequent whole-brain regression analysis showed that drift, rather than diffusion, explained the most variance in delay-period activity in lateral occipital cortex. (timbuschman.com)
Área del LÓBULO OCCIPITAL relacionada con el procesado de la información visual que le llega a través de las VÍAS DE LA VISIÓN. (bvsalud.org)

The clinical signs and symptoms of seizures depend on the location of the epileptic discharges in the cerebral cortex and the extent and pattern of the propagation of the epileptic discharge in the brain. (medscape.com)

The first is a survey of important facts and leading problems concerning the applications of differential geometry in studies on the functional architecture of the visual system. (cornell.edu)

To determine the prevalence and predictors of colour vision defects among Assiut university students and to identify their relationship with self-reported visual function and perceived difficulties in performing daily activities. (who.int)
Prevalence of visual snow syndrome in the UK. (cdc.gov)

CVDs) are the most common X-linked genetic disorder visual activities, and they might also be excluded from in humans. (who.int)

Chromatic information is processed by the visual system both at an unconscious level and at a level that results in conscious perception of color. (mit.edu)

It remains unclear whether both conscious and unconscious processing of chromatic information depend on activity in the early visual cortex or whether unconscious chromatic processing can also rely on other neural mechanisms. (mit.edu)

Results: The neurological signs and symptoms of MD included paresthesias, constriction of visual fields, impairment of hearing and speech, mental disturbances, excessive sweating, and hypersalivation. (cdc.gov)
Treatment of adults with persistent symptoms cortex. (who.int)

Neuropathological lesions involved visual, auditory, and post- and pre-central cortex areas. (cdc.gov)

Acquired CVDs reflect a problem that occurs anywhere along the visual pathway from the photoreceptors to the visual cortex (5). (who.int)
A study conducted occurs anywhere along the visual pathway from the pho- among 267 student volunteers in Menofia University toreceptors to the visual cortex ( 5 ). (who.int)

Magnetocortical steady-state visual evoked fields (ssVEFs) have been shown to vary in amplitude as a function of associative strength. (unboundmedicine.com)

Evidence of dysfunction in the visual association cortex in visual snow syndrome. (cdc.gov)

Here we analyze the emergence of such complex response patterns in a simple model of primary vi(cid:173) sual cortex. (nips.cc)

Data were collected by self-administered questionnaire consisting of: personal characteristics, prior awareness of colour vision defects, difficulties in daily colour vision activities, and visual function. (who.int)

CVDs and self-reported visual function and perceived between individuals who share a common ancestor due difficulties in performing daily activities of study and to geographical isolation or religious belief ( 4 ). (who.int)
the cortex in maintaining this function. (who.int)

This talk will be of interest to people interested in ageing, disease or the primate visual system. (manchester.ac.uk)
It can indicate the underlying disease of the visual afferent system or visual efferent system. (bvsalud.org)

Anatomy47

Organisms18

Diseases12

Chemicals and Drugs13

Analytical, Diagnostic and Therapeutic Techniques and Equipment44

Psychiatry and Psychology58

Phenomena and Processes57

Disciplines and Occupations4

Information Science12

Health Care5

Vision: modular analysis--or not? (1/5702)

On the neural correlates of visual perception. (2/5702)

Transient and permanent deficits in motion perception after lesions of cortical areas MT and MST in the macaque monkey. (3/5702)

Modulation of long-term synaptic depression in visual cortex by acetylcholine and norepinephrine. (4/5702)

Competitive mechanisms subserve attention in macaque areas V2 and V4. (5/5702)

CRE-mediated gene transcription in neocortical neuronal plasticity during the developmental critical period. (6/5702)

MST neuronal responses to heading direction during pursuit eye movements. (7/5702)

Retinotopic mapping of lateral geniculate nucleus in humans using functional magnetic resonance imaging. (8/5702)

Visual Cortex

Visual Pathways

Evoked Potentials, Visual

Visual Perception

Photic Stimulation

Visual Fields

Cerebral Cortex

Brain Mapping

Visual Acuity

Cats

Sensory Deprivation

Dominance, Ocular

Prefrontal Cortex

Pattern Recognition, Visual

Geniculate Bodies

Vision, Monocular

Neurons

Magnetic Resonance Imaging

Orientation

Models, Neurological

Auditory Cortex

Vision, Ocular

Motor Cortex

Somatosensory Cortex

Neuronal Plasticity

Reaction Time

Contrast Sensitivity

Macaca

Functional Laterality

Space Perception

Attention

Motion Perception

Phosphenes

Vision, Binocular

Action Potentials

Image Processing, Computer-Assisted

Ferrets

Psychomotor Performance

Nerve Net

Neural Pathways

Psychophysics

Macaca mulatta

Macaca fascicularis

Fixation, Ocular

Ocular Physiological Phenomena

Occipital Lobe

Neural Inhibition

Form Perception

Blindness

Retina

Parietal Lobe

Darkness

Eye Movements

Discrimination (Psychology)

Dominance, Cerebral

Visual Field Tests

Rats, Long-Evans

Temporal Lobe

Vision Disorders

Cues

Brain

Time Factors

Electroencephalography

Synapses

Entorhinal Cortex

Pulvinar

Electrophysiology

Sensory Thresholds

Depth Perception

Electric Stimulation

Galago

Analysis of Variance

Superior Colliculi

Acoustic Stimulation

Frontal Lobe

Illusions

Microelectrodes

Kidney Cortex

Transcranial Magnetic Stimulation

Eye Enucleation