Visual Cortex: Area of the OCCIPITAL LOBE concerned with the processing of visual information relayed via VISUAL PATHWAYS.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.Evoked Potentials, Visual: The electric response evoked in the cerebral cortex by visual stimulation or stimulation of the visual pathways.Visual Perception: The selecting and organizing of visual stimuli based on the individual's past experience.Photic Stimulation: Investigative technique commonly used during ELECTROENCEPHALOGRAPHY in which a series of bright light flashes or visual patterns are used to elicit brain activity.Visual Fields: The total area or space visible in a person's peripheral vision with the eye looking straightforward.Cerebral Cortex: 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.Brain Mapping: Imaging techniques used to colocalize sites of brain functions or physiological activity with brain structures.Visual Acuity: 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.Cats: 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)Sensory Deprivation: The absence or restriction of the usual external sensory stimuli to which the individual responds.Dominance, Ocular: 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.Pattern Recognition, Visual: Mental process to visually perceive a critical number of facts (the pattern), such as characters, shapes, displays, or designs.Prefrontal Cortex: 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.Neurons: 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.Geniculate Bodies: 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.Vision, Monocular: Images seen by one eye.Magnetic Resonance Imaging: 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.Orientation: Awareness of oneself in relation to time, place and person.Models, Neurological: 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.Auditory Cortex: The region of the cerebral cortex that receives the auditory radiation from the MEDIAL GENICULATE BODY.Vision, Ocular: The process in which light signals are transformed by the PHOTORECEPTOR CELLS into electrical signals which can then be transmitted to the brain.Motor Cortex: 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.Somatosensory 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.Reaction Time: The time from the onset of a stimulus until a response is observed.Neuronal Plasticity: The capacity of the NERVOUS SYSTEM to change its reactivity as the result of successive activations.Protein Sorting Signals: Amino acid sequences found in transported proteins that selectively guide the distribution of the proteins to specific cellular compartments.Contrast Sensitivity: 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.Macaca: 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.Functional Laterality: 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.Space Perception: The awareness of the spatial properties of objects; includes physical space.Attention: Focusing on certain aspects of current experience to the exclusion of others. It is the act of heeding or taking notice or concentrating.Motion Perception: The real or apparent movement of objects through the visual field.Phosphenes: 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.Vision, Binocular: The blending of separate images seen by each eye into one composite image.Action Potentials: Abrupt changes in the membrane potential that sweep along the CELL MEMBRANE of excitable cells in response to excitation stimuli.Image Processing, Computer-Assisted: 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.Psychomotor Performance: The coordination of a sensory or ideational (cognitive) process and a motor activity.Macaca mulatta: 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.Nerve Net: 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 Pathways: Neural tracts connecting one part of the nervous system with another.Psychophysics: 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.Ferrets: 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.Macaca fascicularis: 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.Fixation, Ocular: The positioning and accommodation of eyes that allows the image to be brought into place on the FOVEA CENTRALIS of each eye.Signal Transduction: The intracellular transfer of information (biological activation/inhibition) through a signal pathway. In each signal transduction system, an activation/inhibition signal from a biologically active molecule (hormone, neurotransmitter) is mediated via the coupling of a receptor/enzyme to a second messenger system or to an ion channel. Signal transduction plays an important role in activating cellular functions, cell differentiation, and cell proliferation. Examples of signal transduction systems are the GAMMA-AMINOBUTYRIC ACID-postsynaptic receptor-calcium ion channel system, the receptor-mediated T-cell activation pathway, and the receptor-mediated activation of phospholipases. Those coupled to membrane depolarization or intracellular release of calcium include the receptor-mediated activation of cytotoxic functions in granulocytes and the synaptic potentiation of protein kinase activation. Some signal transduction pathways may be part of larger signal transduction pathways; for example, protein kinase activation is part of the platelet activation signal pathway.Ocular Physiological Phenomena: Processes and properties of the EYE as a whole or of any of its parts.Occipital Lobe: 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.Neural Inhibition: The function of opposing or restraining the excitation of neurons or their target excitable cells.Form Perception: The sensory discrimination of a pattern shape or outline.Retina: 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.Blindness: 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.Time Factors: Elements of limited time intervals, contributing to particular results or situations.Brain: 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.Eye Movements: Voluntary or reflex-controlled movements of the eye.Darkness: The absence of light.Parietal Lobe: 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.Cues: Signals for an action; that specific portion of a perceptual field or pattern of stimuli to which a subject has learned to respond.Discrimination (Psychology): Differential response to different stimuli.Dominance, Cerebral: Dominance of one cerebral hemisphere over the other in cerebral functions.Rats, Long-Evans: 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.Temporal Lobe: 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.Electroencephalography: 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.Visual Field Tests: Method of measuring and mapping the scope of vision, from central to peripheral of each eye.Synapses: 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.Vision Disorders: 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).Electrophysiology: 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.Entorhinal Cortex: 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.Pulvinar: 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.Electric Stimulation: Use of electric potential or currents to elicit biological responses.Signal Processing, Computer-Assisted: Computer-assisted processing of electric, ultrasonic, or electronic signals to interpret function and activity.Acoustic Stimulation: Use of sound to elicit a response in the nervous system.Depth Perception: Perception of three-dimensionality.Analysis of Variance: A statistical technique that isolates and assesses the contributions of categorical independent variables to variation in the mean of a continuous dependent variable.Sensory Thresholds: The minimum amount of stimulus energy necessary to elicit a sensory response.Superior Colliculi: The anterior pair of the quadrigeminal bodies which coordinate the general behavioral orienting responses to visual stimuli, such as whole-body turning, and reaching.Microelectrodes: 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)Galago: 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.Frontal Lobe: The part of the cerebral hemisphere anterior to the central sulcus, and anterior and superior to the lateral sulcus.Illusions: The misinterpretation of a real external, sensory experience.Oxygen: 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.Kidney Cortex: The outer zone of the KIDNEY, beneath the capsule, consisting of KIDNEY GLOMERULUS; KIDNEY TUBULES, DISTAL; and KIDNEY TUBULES, PROXIMAL.Transcranial Magnetic Stimulation: 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.Eye Enucleation: The surgical removal of the eyeball leaving the eye muscles and remaining orbital contents intact.Amblyopia: 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.Parvalbumins: Low molecular weight, calcium binding muscle proteins. Their physiological function is possibly related to the contractile process.Evoked Potentials: 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.Magnetoencephalography: 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.Vision Disparity: 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.Pyramidal Cells: 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.Auditory Perception: The process whereby auditory stimuli are selected, organized, and interpreted by the organism.Scotoma: 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.Optical Illusions: An illusion of vision usually affecting spatial relations.Nonlinear Dynamics: 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.Hemianopsia: 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.Saccades: An abrupt voluntary shift in ocular fixation from one point to another, as occurs in reading.Adaptation, Physiological: The non-genetic biological changes of an organism in response to challenges in its ENVIRONMENT.Animals, Newborn: Refers to animals in the period of time just after birth.Electrodes, Implanted: Surgically placed electric conductors through which ELECTRIC STIMULATION is delivered to or electrical activity is recorded from a specific point inside the body.Color Perception: 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.Cerebellar Cortex: The superficial GRAY MATTER of the CEREBELLUM. It consists of two main layers, the stratum moleculare and the stratum granulosum.Synaptic Transmission: 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.Thalamus: Paired bodies containing mostly GRAY MATTER and forming part of the lateral wall of the THIRD VENTRICLE of the brain.Face: The anterior portion of the head that includes the skin, muscles, and structures of the forehead, eyes, nose, mouth, cheeks, and jaw.Haplorhini: 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).Tupaiidae: 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.Strabismus: 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)Cortical Synchronization: EEG phase synchronization of the cortical brain region (CEREBRAL CORTEX).Signal Detection, Psychological: 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.)Aging: The gradual irreversible changes in structure and function of an organism that occur as a result of the passage of time.Touch: Sensation of making physical contact with objects, animate or inanimate. Tactile stimuli are detected by MECHANORECEPTORS in the skin and mucous membranes.gamma-Aminobutyric Acid: The most common inhibitory neurotransmitter in the central nervous system.Dendrites: Extensions of the nerve cell body. They are short and branched and receive stimuli from other NEURONS.Learning: Relatively permanent change in behavior that is the result of past experience or practice. The concept includes the acquisition of knowledge.Discrimination Learning: Learning that is manifested in the ability to respond differentially to various stimuli.Memory: 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.Feedback: 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.Voltage-Sensitive Dye Imaging: Optical imaging techniques used for recording patterns of electrical activity in tissues by monitoring transmembrane potentials via FLUORESCENCE imaging with voltage-sensitive fluorescent dyes.Mice, Inbred C57BLExcitatory Postsynaptic Potentials: 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.Light: That portion of the electromagnetic spectrum in the visible, ultraviolet, and infrared range.Perceptual Masking: The interference of one perceptual stimulus with another causing a decrease or lessening in perceptual effectiveness.Adaptation, Ocular: 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)Fovea Centralis: 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)Axons: Nerve fibers that are capable of rapidly conducting impulses away from the neuron cell body.Brain Waves: Wave-like oscillations of electric potential between parts of the brain recorded by EEG.Adrenal Cortex: 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.Recognition (Psychology): The knowledge or perception that someone or something present has been previously encountered.Blindness, Cortical: 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)Gyrus Cinguli: 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.Algorithms: A procedure consisting of a sequence of algebraic formulas and/or logical steps to calculate or determine a given task.Calbindin 2: 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.Memory, Short-Term: Remembrance of information for a few seconds to hours.Callithrix: A genus of the subfamily CALLITRICHINAE occurring in forests of Brazil and Bolivia and containing seventeen species.Color: The visually perceived property of objects created by absorption or reflection of specific wavelengths of light.Interneurons: 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.Lighting: 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.Size Perception: The sensory interpretation of the dimensions of objects.Neuropsychological Tests: 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.Wakefulness: A state in which there is an enhanced potential for sensitivity and an efficient responsiveness to external stimuli.Molecular Sequence Data: Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.Perceptual Disorders: 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.Color Vision: 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).Movement: 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.Rats, Sprague-Dawley: 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.Cerebrovascular Circulation: The circulation of blood through the BLOOD VESSELS of the BRAIN.Physical Stimulation: Act of eliciting a response from a person or organism through physical contact.Vibrissae: Stiff hairs projecting from the face around the nose of most mammals, acting as touch receptors.Receptors, N-Methyl-D-Aspartate: 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.Computer Simulation: Computer-based representation of physical systems and phenomena such as chemical processes.Task Performance and Analysis: The detailed examination of observable activity or behavior associated with the execution or completion of a required function or unit of work.Long-Term Synaptic Depression: 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.Electrophysiological Phenomena: 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.Awareness: 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.Optic Chiasm: 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.Vision Tests: A series of tests used to assess various functions of the eyes.Patch-Clamp Techniques: 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.Wheat Germ Agglutinin-Horseradish Peroxidase Conjugate: The lectin wheatgerm agglutinin conjugated to the enzyme HORSERADISH PEROXIDASE. It is widely used for tracing neural pathways.Afferent Pathways: Nerve structures through which impulses are conducted from a peripheral part toward a nerve center.Neurophysiology: The scientific discipline concerned with the physiology of the nervous system.Saimiri: 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.Sensory Aids: Devices that help people with impaired sensory responses.Thalamic Nuclei: Several groups of nuclei in the thalamus that serve as the major relay centers for sensory impulses in the brain.Dark Adaptation: Adjustment of the eyes under conditions of low light. The sensitivity of the eye to light is increased during dark adaptation.Cognition: Intellectual or mental process whereby an organism obtains knowledge.Models, Biological: Theoretical representations that simulate the behavior or activity of biological processes or diseases. For disease models in living animals, DISEASE MODELS, ANIMAL is available. Biological models include the use of mathematical equations, computers, and other electronic equipment.Glutamate Decarboxylase: 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 22.214.171.124.Parahippocampal Gyrus: A convolution on the inferior surface of each cerebral hemisphere, lying between the hippocampal and collateral sulci.Retinal Ganglion Cells: 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.Axonal Transport: 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)Autoradiography: 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)Cerebral Decortication: 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.Macaca radiata: A species of macaque monkey that mainly inhabits the forest of southern India. They are also called bonnet macaques or bonnet monkeys.Consciousness: Sense of awareness of self and of the environment.PrimatesS100 Calcium Binding Protein G: 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.Amino Acid Sequence: The order of amino acids as they occur in a polypeptide chain. This is referred to as the primary structure of proteins. It is of fundamental importance in determining PROTEIN CONFORMATION.Corpus Callosum: 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.Immunohistochemistry: Histochemical localization of immunoreactive substances using labeled antibodies as reagents.Long-Term Potentiation: 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.Neurons, Afferent: Neurons which conduct NERVE IMPULSES to the CENTRAL NERVOUS SYSTEM.Feedback, Sensory: A mechanism of communicating one's own sensory system information about a task, movement or skill.Neocortex: 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.ReadingImagination: A new pattern of perceptual or ideational material derived from past experience.Motion: 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.Reference Values: 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.Data Interpretation, Statistical: Application of statistical procedures to analyze specific observed or assumed facts from a particular study.Nerve Tissue ProteinsElectron Transport Complex IV: 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.Normal Distribution: 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.Image Interpretation, Computer-Assisted: Methods developed to aid in the interpretation of ultrasound, radiographic images, etc., for diagnosis of disease.Electrodes: Electric conductors through which electric currents enter or leave a medium, whether it be an electrolytic solution, solid, molten mass, gas, or vacuum.Optic Nerve: 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.Flicker Fusion: The point or frequency at which all flicker of an intermittent light stimulus disappears.Eye: 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.Reproducibility of Results: The statistical reproducibility of measurements (often in a clinical context), including the testing of instrumentation or techniques to obtain reproducible results. The concept includes reproducibility of physiological measurements, which may be used to develop rules to assess probability or prognosis, or response to a stimulus; reproducibility of occurrence of a condition; and reproducibility of experimental results.Calbindins: 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.Fourier Analysis: Analysis based on the mathematical function first formulated by Jean-Baptiste-Joseph Fourier in 1807. The function, known as the Fourier transform, describes the sinusoidal pattern of any fluctuating pattern in the physical world in terms of its amplitude and its phase. It has broad applications in biomedicine, e.g., analysis of the x-ray crystallography data pivotal in identifying the double helical nature of DNA and in analysis of other molecules, including viruses, and the modified back-projection algorithm universally used in computerized tomography imaging, etc. (From Segen, The Dictionary of Modern Medicine, 1992)Muscimol: 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.Electrooculography: 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.
Increasing the expression of the RGS14 protein in the V2 secondary visual cortex of mice promotes the conversion of short-term ... "RGS14 is multifunctional scaffold that integrates G protein and Ras/Raf MAPkinase signaling pathways". Cellular Signalling.: in ... "Role of layer 6 of V2 visual cortex in object-recognition memory". Science. 325 (5936): 87-9. doi:10.1126/science.1170869. PMID ... Regulator of G-protein signaling 14 (RGS14) is a protein that in humans is encoded by the RGS14 gene. RGS14 is a member of the ...
Tuned responses of astrocytes and their influence on hemodynamic signals in the visual cortex. Science 320: 1638-1643, 2008. ... Subthreshold facilitation and suppression in primary visual cortex revealed by intrinsic signal imaging. Proceedings of the ... The coordinated mapping of visual space and stimulus features in visual cortex. Neuron 47: 267-280, 2005. Tropea, D., G. ... which normally projects to the visual cortex, was induced to project to structures that normally process hearing. Visual input ...
"Spatial and Temporal Properties of Cone Signals in Alert Macaque Primary Visual Cortex" (PDF). The Journal of Neuroscience. ... Conway, Bevil R. (15 April 2001). "Spatial Structure of Cone Inputs to Color Cells in Alert Macaque Primary Visual Cortex (V-1 ... Conway specialises in visual perception in his scientific work, and he often explores the limitations of the visual system in ... Much of Conway's research is guided by the underlying thought that visual art can be used to reveal insights about how visual ...
Schummers J, Yu H, Sur M (2008). "Tuned Responses of Astrocytes and Their Influence on Hemodynamic Signals in the Visual Cortex ... calcium signalling and paravascular lipid transport in the brain, the findings point to the adoption of a function in the CNS ... intracellular lipid accumulation and pathological signalling among astrocytes. Although further experiments are needed to parse ... "Paravascular microcirculation facilitates rapid lipid transport and astrocyte signaling in the brain". Scientific Reports. 3 ( ...
... which relays visual inputs from the retina to the visual cortex, have been shown to generate the BOLD signal correctly when ... These signals get to the primary visual cortex via the thalamus in tens of milliseconds. Neuronal activity related to the act ... In both the primary motor cortex and the visual cortex, the HDR amplitude scales linearly with duration of a stimulus or ... Researchers have checked the BOLD signal against both signals from implanted electrodes (mostly in monkeys) and signals of ...
Historically, they were thought to represent the activity of the visual cortex in an idle state. More recent papers have argued ... to cause signals to appear on an EEG readout, causing false signals to be interpreted as healthy alpha waves. This finding ... An alpha-like variant called mu (μ) can be found over the motor cortex (central scalp) that is reduced with movement, or the ... Kolev V, Başar-Eroglu C, Aksu F, Başar E (April 1994). "EEG rhythmicities evoked by visual stimuli in three-year-old children ...
Superimposing and processing these monocular visual signals allow the visual cortex to generate binocular and stereoscopic ... For example, the right visual cortex receives the temporal visual field from the left eye, and the nasal visual field from the ... Transformations of the visual field toward the visual map on the primary visual cortex. Human brainstem anterior view Optic ... The crossing over of optic nerve fibres at the optic chiasm allows the visual cortex to receive the same hemispheric visual ...
Signals from the retina ascend through the lateral geniculate nucleus and activate neurons in primary visual cortex. Primary ... visual cortex sends the information about the target to the middle temporal visual cortex, which responds very selectively to ... The "go"-signal from the cortex and the superior colliculus is relayed to several pontine nuclei, including the dorsolateral ... Temporal properties of visual motion signals for the initiation of smooth pursuit eye movements in monkeys. J Neurophysiol. ...
This process is closely related to processes in the primary visual cortex. Jones and Palmer showed that the real part of the ... 12th IEEE Workshop on Neural Networks for Signal Processing, pp. 365 - 374, 2002. Peeta Basa Pati and A. G. Ramakrishnan, "Word ... Some authors claim that simple cells in the visual cortex of mammalian brains can be modeled by Gabor functions. Thus, image ... First International Conference on Advances in Visual Computing (ISVC05), Nevada, USA, LNCS 3804, Springer Verlag, Dec. 5-7, ...
Thalamus - The thalamus is involved in relaying sensory and motor signals to the cerebral cortex, especially visual stimuli. ... The fifth "Occipital/ Visual Association" group included areas V8 and V4 of the primary visual cortex, the medial temporal lobe ... The third "Medial Prefrontal Cortex" group included the dorsal medial prefrontal cortex, pregenual anterior cingulate cortex, ... group included posterior cingulate cortex and area V1 of the primary visual cortex. The authors suggest that these regions play ...
He also worked with the visual system of macaque monkeys, and found: its parallel processing of visual signals; the nature of ... More recently, he has been studying how color is represented in the visual cortex, as a follow-up to his earlier work on ... Johnson EA Hawken MJ and Shapley RM (2001) The Spatial Transformation of Color in the Primary Visual Cortex of the Macaque ... Johnson EN, Hawken MJ, Shapley R. (2004) Cone Inputs in Macaque Primary Visual Cortex. J Neurophysiol. 91:2501-14. Johnson EN, ...
"Fast synaptic signaling by nicotinic acetylcholine and serotonin 5-HT3 receptors in developing visual cortex". J Neurosci. 17 ( ... and in ferret visual cortex. 5-HT3 receptors are also present on presynaptic nerve terminals. There is some evidence for a role ...
This signal communicates to the brain that the saccade has concluded. Prompted by this signal, the visual cortex once again ... This sensory input is sent directly to the visual cortex to be processed. After visual processing, we consciously perceive this ... In order to prevent the visual cortex from processing blurred sensory information, visual information collected by the eyes ... For the student, his eyes have now reached the clock and his brain's visual cortex begins to process information from his eyes ...
The visual effect is described as the loss of vision as the brain cuts off the unchanging signal from the eyes. The result is " ... The noise is interpreted in the higher visual cortex, and gives rise to hallucinations. It has been most studied with vision by ... The effect is the result of the brain amplifying neural noise in order to look for the missing visual signals.[better source ... Cortex 44 (2008) 1364 - 1378. Elsevier. [permanent dead link] Williams, William F. (2013 edition). Encyclopedia of ...
His laboratory has worked to develop methods for identifying and measuring visual field maps in visual cortex. Recently, he and ... He and his group are hoping to understand how visual signals and structures must develop to permit rapid, skilled reading. This ... Specifically, they are measuring the responses in visual cortex of children, aged 8-12, as the children become skilled readers ... His work in visual neuroscience uses both functional MRI and computational modeling to understand the action of the visual ...
The signals from retinal waves drive the activity in the dorsal lateral geniculate nucleus (dLGN) and the primary visual cortex ... This signaling happens before bipolar cells form connections in the inner plexiform layer. SACs are thought to be the source of ... She also believed being able to figure out the signals encoded by retinal waves, may allow scientists to better understand how ... Wong also speculated that specific parts of the visual system, such as the ocular dominance columns, require some form of ...
... reduces adult visual cortex plasticity by binding to nicotinic acetylcholine receptors (NAchR) and diminishing ... Similarly, an infusion of physostigmine to increase acetylcholine signaling prompted recovery from amblyopia in wild type mice ... Morishita H, Miwa JM, Heintz N, Hensch TK (Nov 2010). "Lynx1, a cholinergic brake, limits plasticity in adult visual cortex". ... Transgenic mice without Lynx1 expression do not have a normal critical period of neuroplasticity in the visual cortex for ...
... which send signals to the visual cortex, which in turn processes those sensations into a subjective perception of color. Color ... Zeki, S. (1983). Colour coding in the cerebral cortex: The reaction of cells in monkey visual cortex to wavelengths and colours ... Spatial and Temporal Properties of Cone Signals in Alert Macaque Primary Visual Cortex (V1). Journal of Neuroscience 26(42): ... The physiological basis for color constancy is thought to involve specialized neurons in the primary visual cortex that compute ...
These signals travel along the optic nerve fibers to the brain, where they are interpreted as vision in the visual cortex. ... Eye movement is thus very important for visual perception, and any failure can lead to serious visual disabilities. To see a ... Occipital lobe Visual cortex Cerebellum Midbrain Pretectal area - Pretectal nuclei Superior colliculus Brain stem Superior ... The visual system in the brain is too slow to process that information if the images are slipping across the retina at more ...
The behaviour of primary visual cortex neurons seems to be in agreement with the one hypothesized by an isomorphic filling-in ... These signals are strong because receptive fields are exposed to contrast, and reliable because the border produces continuous ... 1999) performed an experiment aimed at determining if surface activity of cells in monkey primary visual cortex changed in ... 2006). "No functional magnetic resonance imaging evidence for brightness and color filling-in in early human visual cortex". J ...
The final visual signals will be sent to the thalamus and cerebral cortex, where additional lateral inhibition occurs. Sensory ... The central rod will send the light signals directly to bipolar cells which in turn will relay the signal to the ganglion cells ... Compare unsharp masking in digital processing). This mechanism also creates the Mach band visual effect. Visual Lateral ... signal to the brain, whereas different rods on the outside of the stimulus will send a "dark" signal to the brain due to ...
... are first found in the visual cortex in layer 4. Binocular neurons appear in the striate cortex (V1), the prestriate cortex (V2 ... Binocular neurons receive inputs from both the right and left eyes and integrate the signals together to create a perception of ... Poggio, G; B. Motter; S. Squatrito; Y. Trotter (1985). "Responses of neurons in visual cortex (V1 and V2) of the alert mecaque ... Two main classes of cells in visual cortex were identified by David H. Hubel and Torsten Wiesel in 1962 through their ...
... sensory signals from the eyes are transmitted to the thalamus and then to the primary visual cortex; inside the cerebral cortex ... Francis Crick and Christof Koch (1995). "Are we aware of neural activity in primary visual cortex?". Nature. 375 (6527): 121- ... Battaglia PW, Jacobs RA, Aslin RN (2003). "Bayesian integration of visual and auditory signals for spatial localization". ... it is possible for subjects to report a lack of awareness even when areas such as the primary visual cortex show clear ...
In the CNS, diphenhydramine readily crosses the blood-brain barrier, exerting effects within the visual and auditory cortex. ... causing confusion and temporary amnesia due to decreased acetylcholine signaling. Toxicology also manifests in the autonomic ...
Transient attention enhances perceptual performance and fMRI response in human visual cortex. Neuron, 45, 469-477. Herrmann K, ... Support for signal enhancement. Vision Research, 40, 1203-1215. Liu T, Pestilli F & Carrasco M (2005) ... Carrasco, M. (2011). Visual Attention: The past 25 years. Vision Research, 51, 1484-1525. Anton-Erxleben, K. & Carrasco, M. ( ... Carrasco was the president of the Vision Sciences Society (2011-12), the largest society dedicated to the study of visual ...
A bilateral temporal visual field defect (due to compression of the optic chiasm) or dilation of the pupil, and the occurrence ... Necrotic cells send the wrong chemical signals which prevent phagocytes from disposing of the dead cells, leading to a buildup ... although glial cells outnumber neurons roughly 4 to 1 in the cerebral cortex. Glia come in several types, which perform a ... visual field impairment, impaired sense of smell, impaired hearing, facial paralysis, double vision, or more severe symptoms ...
Value-driven attentional priority signals in human basal ganglia and visual cortex.. Anderson BA1, Laurent PA2, Yantis S2. ... Value-Driven Attentional Priority Signals in Human Basal Ganglia and Visual Cortex ... Value-Driven Attentional Priority Signals in Human Basal Ganglia and Visual Cortex ... Value-Driven Attentional Priority Signals in Human Basal Ganglia and Visual Cortex ...
Circuits for Local and Global Signal Integration in Primary Visual Cortex. Alessandra Angelucci, Jonathan B. Levitt, Emma J. S. ... Circuits for Local and Global Signal Integration in Primary Visual Cortex. Alessandra Angelucci, Jonathan B. Levitt, Emma J. S. ... Circuits for Local and Global Signal Integration in Primary Visual Cortex Message Subject (Your Name) has forwarded a page to ... Circuits for Local and Global Signal Integration in Primary Visual Cortex. Alessandra Angelucci, Jonathan B. Levitt, Emma J. S ...
Directional Signals in the Prefrontal Cortex and in Area MT during a Working Memory for Visual Motion Task. Daniel Zaksas and ... Directional Signals in the Prefrontal Cortex and in Area MT during a Working Memory for Visual Motion Task ... Directional Signals in the Prefrontal Cortex and in Area MT during a Working Memory for Visual Motion Task ... Directional Signals in the Prefrontal Cortex and in Area MT during a Working Memory for Visual Motion Task ...
... such as the primary visual cortex (V1). Ocular dominance columns, one type of module in V1, are found in many primate species ... such as the primary visual cortex (V1). Ocular dominance columns, one type of module in V1, are found in many primate species ... Intrinsic-signal optical imaging reveals crypticocular dominance columns in primary visual cortex of New World owl monkeys. ... Functional organization of visual cortex in the prosimian bush baby revealed by optical imaging of intrinsic signals. J. ...
... Sci. Rep. 6 ... Attention enhances stimulus representations in macaque visual cortex without affecting their signal-to-noise level. Mohammad ... of macaque visual cortex to moving random dots pattern of various motion coherences, i.e. signal-to-noise ratios. Our data show ... common to neurons in visual cortex. Such hypotheses are based on the observation that the CRF of neurons in extrastriate visual ...
Using optical mapping of the internal signal to test the function of the visual cerebral cortex in mammals I. V. Bondar, E. E. ... "Using optical mapping of the internal signal to test the function of the visual cerebral cortex in mammals," J. Opt. Technol. ... It is shown to be possible in principle to use optical mapping of the internal signal to objectively test the visual function: ... Optical mapping of the internal signal is a unique method of studying the brain and makes it possible to investigate the ...
Correlations of BOLD Signal Change.. Four regions of interest (ROIs) were defined in the left and right IPS and PM cortex. ... 2012) Spatiotemporal profiles of visual processing with and without primary visual cortex. Neuroimage 63:1464-1477. ... 1995) Parameters affecting conscious versus unconscious visual discrimination with damage to the visual cortex (V1). Proc Natl ... Unilateral damage to the primary visual cortex (V1) leads to clinical blindness in the opposite visual hemifield, yet ...
Blood oxygenation level-dependent (BOLD) total and extravascular signal changes and ΔR2* in human visual cortex at 1.5, 3.0 and ... Blood oxygenation level-dependent (BOLD) total and extravascular signal changes and ΔR2* in human visual cortex at 1.5, 3.0 and ... Blood oxygenation level-dependent (BOLD) total and extravascular signal changes and ΔR2* in human visual cortex at 1.5, 3.0 and ... T1 - Blood oxygenation level-dependent (BOLD) total and extravascular signal changes and ΔR2* in human visual cortex at 1.5, ...
... measurement of brain surface potentials in five human subjects during a visual search task. Comparison of visual search epochs ... measurement of brain surface potentials in five human subjects during a visual search task. Comparison of visual search epochs ... In the θ and β ranges, the coupling of phase to broadband change is dynamic during visual processing, decreasing in some ... In the θ and β ranges, the coupling of phase to broadband change is dynamic during visual processing, decreasing in some ...
... neuroimaging and neurophysiological studies has accumulated suggesting that basic visual perceptual and cognitive... ... contribute to the attentional selection of visual stimuli and to the attention-related filtering of visual signals in cortex. ... Interaction of Visual and Oculomotor Signals in Cortex Moore, Tirin Stanford University, Stanford, CA, United States ... In the present proposal, we plan to further examine the influence of saccade-related signals on visual representations in a set ...
Parallel visual system discovered in mouse cerebral cortex. This study shows the discovery of a second... ... Then green cells induced second signalling to neighboring blue sender cells to activate different cadherin and red signal, ... One group of cells acted as signal sender cells and expressed a ligand (CD19 protein) on their surfaces. These cells also ... The second group of cells acted as signal receiver cells and expressed a SynNotch receptor capable of binding to the sender ...
Cortical activity in the primary visual cortex (V1) was then stimulated by direct manipulation of the visual sensory inputs. ... The SARE reporter virus-infected neurons in layers 2/3 of the visual cortex. Activity-reporter GFP signals were detected in the ... we quantified the extent of visual activation in layers 2/3 of the primary visual cortex. The virus-injected mice were first ... Viral Reporter Assay in Mouse Visual Cortex.. Production of lentivirus-infected mice is described in SI Materials and Methods. ...
A day by day log of cortical electric activity in the mouse visual cortex was published in the Journal of Neuroscience by ... Scientists chart how brain signals connect to neurons. December 14, 2017 Scientists at Johns Hopkins have used supercomputers ... Researcher develops mouse model for studying development of visual cortex. November 30, 2016 A day by day log of cortical ... Development of Activity in the Mouse Visual Cortex, Journal of Neuroscience (2016). DOI: 10.1523/JNEUROSCI.1903-16.2016 ...
... the visual cortex in the left hemisphere receives signals from the right visual field, and the visual cortex in the right ... Visual area V2, or secondary visual cortex, also called prestriate cortex, is the second major area in the visual cortex, ... Middle temporal visual area (V5). The middle temporal visual area (MT or V5) is a region of extrastriate visual cortex. ... Third visual cortex, including area V3. The term third visual complex refers to the region of cortex located immediately ...
We demonstrate that the mouse visual cortex has all the necessary elements to implement local estrogenic signaling during ... These findings suggest that the visual system, in particular the visual cortex, may be a site that is influenced by E2. It is ... presence of ARO and ERs in visual cortical neurons makes it highly likely that estrogenic signaling in the adult visual cortex ... Visual experience and deprivation bidirectionally modify the composition and function of NMDA receptors in visual cortex. ...
... signaling pathways through discrete neuromodulator receptor subtypes dictates the direction of plasticity induced in visual ... Advances in understanding visual cortex plasticity.. McCoy PA1, Huang HS, Philpot BD. ... Activation of plasticity gene expression contributes to the ocular dominance plasticity in the visual cortex. LGN: lateral ... Visual cortical plasticity can be either rapid, occurring in response to abrupt changes in neural activity, or slow, occurring ...
Bottom-Up Dependent Gating of Frontal Signals in Early Visual Cortex. By Leeland B. Ekstrom, Pieter R. Roelfsema, John T. ... Higher brain centers can modulate activity in the cortical regions that directly receive visual input, but only when a visual ... Signal-Mediated Dynamic Retention of Glycosyltransferases in the Golgi. By Linna Tu, William C. S. Tai, Lu Chen, David K. ... Recent studies offer insights into how a molecular signal controls the growth and patterning of the digits on vertebrate limbs ...
Visual predictions in different layers of visual cortex. Abstract:. Our brain imaging research has contributed to what is now ... I will argue that the frequency band (30-150 Hz) used in natural and artificial alarm signals maximises neural responses in the ... As previously observed in visual cortex, LFP power in gamma frequencies (40-100 Hz) was strongest in superficial layers (L1-3 ... to uncover contextual feedback information to superficial layers of primary visual cortex. These paradigms allow us to measure ...
... and signal changes (ΔS/S) in response to visual stimulation (flashing checkerboard; f = 8 Hz) were investigated sequentially ( ... of BOLD contrast and for modelling approaches that aim to extract quantitative metabolic parameters from the BOLD signal. Using ... Blood oxygenation level-dependent (BOLD) total and extravascular signal changes and ΔR2* in human visual cortex at 1.5, 3.0 and ... Blood oxygenation level-dependent (BOLD) total and extravascular signal changes and ΔR2* in human visual cortex at 1.5, 3.0 and ...
Signal analyzer with SLM compensation Proceedings of SPIE (March 10 2000) Robust visual tracking with dual spatio-temporal ... The visual stimulus was a circular, black and white, alternating checkerboard. In four of five subjects the visual cortex was ... Activation of visual cortex imaged by 24 channel near-infrared spectroscopy. Kazumi Takahashi; S. Ogata; R. Yamamoto; S. ... This is the first reported use of a NIRSimaging system for assessing hemodynamic changes in the human visual cortex. The ...
A new study finds that, in mice, location-related signals affect activity in the primary visual cortex. ... Striate cortex. Definition. The striate cortex is the part of the visual cortex that is involved in processing visual ... The visual callosal pathway reciprocally connects mammalian visual cortices and is proposed to facilitate activation of ... Spatial contextual effects in primary visual cortex limit feature representation under crowding Visual crowding can strongly ...
Researchers have identified how signals from the visual and prefrontal cortices may interact to help us recognize shapes that ... Home Health Researchers have identified how signals from the visual and prefrontal cortices may... ... Researchers have identified how signals from the visual and prefrontal cortices may interact to help us recognize shapes that ... the brain generates signals in certain areas of the visual cortex - the part for sight. ...
And then? ,, [INAUDIBLE] ,, To LGN, yes, and visual cortex. Good, thanks. So thats actually the light signal. First they ... Right? So, in the visual system how does the visual information flow from the photoreceptor to the visual cortex? [FOREIGN] So ... Then this is the key difference between these two signaling. In the G protein signaling you have a huge amplification. But then ... The response, theyre in the, this tract treatment under their hair cell cannot transfuse the light signal, to electric signal ...
recognition, so we imagine that signals were processed in early visual cortex. ... The majority of the human cerebral cortex is multi-modal cortex that associates signals derived from one or more modal systems ... Unit 2 Neural signaling (weeks 3-4). This unit addresses the fundamental mechanisms of neuronal excitability, signal generation ... cortices that are localized to each cerebral lobe. So lets begin and I want to first relate what we will be talking about ...
Synaptic integration in the visual cortex.. Joan Press, Seniors Honors Coordinator (Rosenstiel Center) Developmental immunology ... BIOL 428d Signal Transduction Mr. Ren. BIOL 429d Developmental Neurobiology Ms. Sengupta. BIOL 430d Cell Biology of Yeast Ms. ... BIOL 409d Biophysics of Visual Transduction Mr. Lisman. BIOL 410d Plant Development Mr. Klein. BIOL 411d Gene Control Mr. Wangh ... Signal transduction.. Michael Rosbash (Center for Complex Systems) RNA processing and molecular neurobiology.. Joan Rutila ...
Primary visualJournal of NeuroscieParietalBrain'sOccipitalEarly visual cortexFMRIReceptive fieldSensory cortexNeurosciencePhysiologyArranged to approximately tonotopically matchMacaqueSubject's visual cortexAreas of the visual cortexResponsesSomatosensory cortexMonkeysOptic nerveRight visual cortexInputsNeuronPlurality of electrical contactsRetinaFrontalCircuitsSynapticOrientationElectrical signalsMotor cortexFunctionallyModulationInhibitionRepresentationAcuitySpatial summation
- Contrast-dependent changes in spatial summation and contextual modulation of primary visual cortex (V1) neuron responses to stimulation of their receptive field reveal long-distance integration of visual signals within V1, well beyond the classical receptive field (cRF) of single neurons. (jneurosci.org)
- Modularity, the term often used to describe the inhomogeneous nature of the neocortex, is without a doubt an important organizational principle of early sensory areas, such as the primary visual cortex (V1). (frontiersin.org)
- Other types of modular segregation have been reported, but possibly most studied is the segregation of neurons activated or dominated by stimulation from either the ipisilateral eye or the contralateral eye in the primary visual cortex (the striate cortex, V1 or area 17). (frontiersin.org)
- Our findings in one patient with early primary visual cortex damage suggest that this nonconscious visuomotor ability depends partly on the compensatory activity of the intact hemisphere, which can be dynamically recruited through the corpus callosum. (pnas.org)
- Unilateral damage to the primary visual cortex (V1) leads to clinical blindness in the opposite visual hemifield, yet nonconscious ability to transform unseen visual input into motor output can be retained, a condition known as "blindsight. (pnas.org)
- The part of the visual cortex that receives the sensory inputs from the thalamus is the primary visual cortex, also known as visual area 1 (V1, Brodmann area 17), and the striate cortex. (wikipedia.org)
- The primary visual cortex (V1) is located in and around the calcarine fissure in the occipital lobe . (wikipedia.org)
- They originate from primary visual cortex. (wikipedia.org)
- Here we show that estrogen-associated circuits are highly prevalent in the mouse primary visual cortex (V1). (pubmedcentralcanada.ca)
- Visual nerves run straight from the eye to the primary visual cortex to the Visual Association cortex. (wikipedia.org)
- The part of the visual cortex that receives the sensory inputs from the thalamus is the primary visual cortex, also known as visual area 1 (V1), and the striate cortex. (wikipedia.org)
- Here, the authors show that perceptual crowding is similar in monkeys and humans, and that feature encoding in neuronal populations in primary visual cortex is limited for displays inducing crowding. (nature.com)
- A new study finds that, in mice, location-related signals affect activity in the primary visual cortex. (nature.com)
- In the mammalian visual system, early stages of visual form processing begin with orientation-selective neurons in primary visual cortex (V1). (sciencemag.org)
- In classical models of the visual system, information flows from 'primary' visual cortex (V1) to more specialized, downstream areas that focus for example on image movement or image form. (ucl.ac.uk)
- Each panel in the background shows the traced axon of a single neuron from the upper layers of primary visual cortex. (ucl.ac.uk)
- Up until now, it had remained unclear as to whether information transfer from primary visual cortex was largely "one neuron - one target area", or if individual neurons distributed their signals across multiple downstream areas. (ucl.ac.uk)
- the scientists found that these were the exception and that the majority of primary visual cortex neurons broadcast information to multiple targets. (ucl.ac.uk)
- The mouse primary visual cortex (V1) neurons were found to have a high degree of projectional diversity and most of the individual layer 2/3 neurons were found to distribute information to multiple areas rather than projecting to a single target. (ucl.ac.uk)
- Single and multiple spikes as well as local field potentials were recorded simultaneously from several locations in the primary visual cortex (A17 and A18) using 7 or 19 individually advanceable fibermicroelectrodes (250 or 330 μm apart). (springer.com)
- Then the signals enter the primary visual cortex. (i4u.com)
- Brief (2-3d) monocular deprivation (MD) during the critical period induces a profound loss of responsiveness within binocular (V1b) and monocular (V1m) regions of rodent primary visual cortex. (elifesciences.org)
- 3. We find that the variability of firing is much higher in cells of primary visual cortex in the anesthetized cat than in slice. (caltech.edu)
- Using the primary visual cortex (V1) as a model, we asked whether cortical function or plasticity are affected when the β-catenin gene is disrupted. (deepdyve.com)
- We focus on studies of ongoing local field potential (LFP) data obtained simultaneously from multiple sites in the primary visual cortex in two types of experiments in which electrode contacts were spaced either along the cortical surface or at different laminar positions. (dovepress.com)
- The primary visual cortex is the most studied visual area in the brain. (wikipedia.org)
- clarification needed] The functionally defined primary visual cortex is approximately equivalent to the anatomically defined striate cortex. (wikipedia.org)
- The primary visual cortex is divided into six functionally distinct layers, labeled 1 to 6. (wikipedia.org)
- The average number of neurons in the adult human primary visual cortex in each hemisphere has been estimated at around 140 million. (wikipedia.org)
- From the LGN, the signals continue to the primary visual cortex, where further visual processing takes place. (medscape.com)
- The brain first perceives changes in visual input (local motion) in the primary visual cortex. (scienceblog.com)
- The third dimension in the primary visual cortex. (berkeley.edu)
- Cholinergic modulation of response gain in the primary visual cortex of the macaque. (semanticscholar.org)
- ACh modulates neuronal activity throughout the cerebral cortex, including the primary visual cortex (V1). (semanticscholar.org)
- Acetylcholine dynamically controls spatial integration in marmoset primary visual cortex. (semanticscholar.org)
- Cholinergic modulation of response properties and orientation tuning of neurons in primary visual cortex of anaesthetized Marmoset monkeys. (semanticscholar.org)
- Mechanisms underlying orientation selectivity of neurons in the primary visual cortex of the macaque. (semanticscholar.org)
- In this study, we used these technical improvements to determine the critical period for orientation plasticity in cat primary visual cortex. (plos.org)
- The majority of these nerves go to the back of brain to the primary visual cortex. (lukew.com)
- The primary visual cortex is the starting point for visual processing. (lukew.com)
- Then, the optic tract projects to the primary visual cortex in the occipital lobe at the back of the brain. (medicalnewstoday.com)
- Negative BOLD signals and CBF decreases were shown for ring stimuli in primary visual cortex (V1). (ismrm.org)
- Here we show that contrast adaptation in mouse primary visual cortex depends on the behavioral relevance of the stimulus. (nih.gov)
- The physiological basis for color constancy is thought to involve specialized neurons in the primary visual cortex that compute local ratios of cone activity, which is the same calculation that Land's retinex algorithm uses to achieve color constancy. (wikipedia.org)
- A day by day log of cortical electric activity in the mouse visual cortex was published in the Journal of Neuroscience by George Washington University (GW) researcher Matthew Colonnese, Ph.D. This research is the first to establish a mouse model for human fetal electrographic development. (medicalxpress.com)
- Development of Activity in the Mouse Visual Cortex, Journal of Neuroscience (2016). (medicalxpress.com)
- Compensation of cognitive and motor deficits after unilateral lesions to the frontal or parietal cortex has been extensively investigated in neurological patients ( 2 , 3 ) as well as animal models ( 4 ), revealing transcallosal recruitment of homologous areas in the intact hemisphere. (pnas.org)
- The dorsal stream begins with V1, goes through Visual area V2, then to the dorsomedial area (DM/V6) and medial temporal area (MT/V5) and to the posterior parietal cortex . (wikipedia.org)
- Coding of intention in the posterior parietal cortex. (psu.edu)
- Space and attention in parietal cortex. (psu.edu)
- Multimodal representation of space in the posterior parietal cortex and its use in planning movements Annu Rev Neurosci 20:303-330. (psu.edu)
- Memory related motor planning activity in posterior parietal cortex of macaque. (psu.edu)
- Monkey posterior parietal cortex neurons antidromically activated from superior colliculus. (psu.edu)
- Organization of visual inputs to the inferior temporal and posterior parietal cortex in macaques - JS, LG, et al. (psu.edu)
- The thalamic relations of the caudal inferior parietal lobule and the lateral prefrontal cortex in monkeys: divergent cortical projections from cell clusters in the medial pulvinar nucleus. (psu.edu)
- Visuomotor predictionerrors modulate EEG activity over parietal cortex. (usherbrooke.ca)
- Selective attenuation ofvisual reafferent signals in parietal cortex during movement. (usherbrooke.ca)
- Seeds in the vestibular [parietal operculum (OP2)], the parietal [posterior parietal cortex (PPC);7A, hIP and the visual cortex (VC) were used for the analysis. (uni-muenchen.de)
- Activity in human visual and parietal cortex reveals object-based attention in working memory. (uni-frankfurt.de)
- Rockville, MD - Researchers have long known of the brain's ability to learn based on visual motion input, and a recent study has uncovered more insight into where the learning occurs. (scienceblog.com)
- The sense organ for vision is an exquisitely evolved biological instrument for turning light into the brain's language of electrical signals. (dana.org)
- The optic nerve carries signals of light, dark, and colors to the brain's visual cortex. (uhhospitals.org)
- The optic nerve's 1 million fibers carry the signal to the brain's visual cortex, the place where we experience vision. (technologyreview.com)
- In the θ and β ranges, the coupling of phase to broadband change is dynamic during visual processing, decreasing in some occipital areas and increasing in others, in a gyrally specific pattern. (frontiersin.org)
- In mammals, it is located in the posterior pole of the occipital lobe and is the simplest, earliest cortical visual area. (wikipedia.org)
- Essentially all visual prosthesis efforts share a common principle of providing focal electrical stimulation to intact visual structures (including the retina, optic nerve, lateral geniculate nucleus (LGN) and occipital visual cortex) evoking the sensation of discrete points of light called phosphenes. (utah.edu)
- The eye has many features of a camera, beginning with the cornea and ending with the occipital (visual) cortex. (medscape.com)
- Our results point to slow spontaneous modulations in firing rate and gamma LFP as the likely correlates of spontaneous fMRI fluctuations in the human sensory cortex. (nature.com)
- fMRI characterization of visual working memory recognition. (uni-frankfurt.de)
- Sequence utility is demonstrated for high-resolution rFOV functional MRI (fMRI) in the visual cortex. (stanford.edu)
- Each portion of a subject's visual cortex was scanned during each session in the fMRI. (innovations-report.com)
- For unknown reasons, the fMRI signals from the monkeys were weaker than those from the humans," Orban said. (innovations-report.com)
- In principle, inhibition may increase or decrease fMRI signals depending on local circuitry. (ismrm.org)
- By definition, the receptive field is the region within the entire visual field that elicits an action potential . (wikipedia.org)
- For example, in the inferior temporal cortex (IT), a neuron may fire only when a certain face appears in its receptive field. (wikipedia.org)
- Primary visual coding can be characterized by the receptive field (RF) properties of single neurons. (springer.com)
- Implicit in the neuroscience community was that the monkey cortex is a good model for the human cortex," said James Todd, a study co-author and a professor of psychology at Ohio State University. (innovations-report.com)
- According to modern neuroscience, object perception involves bottom-up signals from sensory organs and top-down signals from internal mind's representations (memories) of objects. (mdpi.com)
- It is a major benefit to have a developmental mouse model, since there are so many other mouse models of disease and there is such a large gap in our understanding of the normal progression of the developing cortex," said Colonnese, assistant professor of pharmacology and physiology at the GW School of Medicine and Health Sciences. (medicalxpress.com)
- Here we report the effect of spatial attention on responses in the medial-temporal area (MT) of macaque visual cortex to moving random dots pattern of various motion coherences, i.e. signal-to-noise ratios. (pubmedcentralcanada.ca)
- To address this, we recorded spike and LFP data from the frontal cortex (area PMd and SEF) of a macaque monkey with multiple 16 and 24 channel linearly-spaced multicontact probes as the animal performed a visual working memory (WM) task. (dartmouth.edu)
- Topography of visual cortex connections with frontal eye field in macaque: convergence and segregation of processing streams. (psu.edu)
- Perceptual and motor processing stages identified in the activity of macaque frontal eye field neurons during visual search. (psu.edu)
- We investigated this question using intrinsic-signal optical imaging of macaque V1, V2 and V4, along with computer simulations of the neural population responses. (royalsocietypublishing.org)
- Differential expression of muscarinic acetylcholine receptors across excitatory and inhibitory cells in visual cortical areas V1 and V2 of the macaque monkey. (semanticscholar.org)
- These neurophysiological responses require integration of visual signals beyond the RF of single V1 neurons and thus cannot be easily explained by classical RF concepts. (jneurosci.org)
- Contrast might have this special role not only because it is encoded by a monotonic function (in contrast to circular stimulus properties such as orientation and motion direction) but also because it is the only stimulus property that influences responses in all neurons of visual cortex. (pubmedcentralcanada.ca)
- Using intrinsic signal imaging and chronic visually evoked potential recordings, we found that Arc(-/-) mice did not exhibit depression of deprived-eye responses or a shift in ocular dominance after brief monocular deprivation. (nih.gov)
- Here we examined perceptual and neural responses to words with and without this visual head start. (elifesciences.org)
- Neural responses were measured from electrodes implanted over auditory association cortex in the posterior superior temporal gyrus (pSTG) of epileptic patients. (elifesciences.org)
- The presence of visual speech suppressed responses to auditory speech, more so for words with a visual head start. (elifesciences.org)
- Donaldson IML, Nash JRG (1975) The effect of a chronic lesion in cortical area 17 on the visual responses of units in area 18 of the cat. (springer.com)
- Typically, monocular deprivation in early postnatal days leads to a shift in the dominant responses of primary visual cortical neurons to the non-deprived, experienced eye - . (plos.org)
- However, whether PNECs can function in vivo to translate exogenous airway signals such as allergens into the cascade of downstream responses is unknown. (sciencemag.org)
- However, unlike this basic Bauplan of the neocortex, primary somatosensory cortex (S1) possesses a very well-developed layer IV and thus qualifies itself as a typical koniocortical area, as all primary sensory cortical areas. (scholarpedia.org)
- S1 represents a certain nomenclature of cortical areas and stands for primary somatosensory cortex. (scholarpedia.org)
- By the time it hits the ganglion layer, the analog light signal has been completely digitized-it is now a series of nerve impulses which the ganglion cells proceed to pump into the optic nerve. (technologyreview.com)
- What they needed to know was whether people blinded by a disease like RP retained enough intact retinal circuitry to permit them to get a signal into the optic nerve. (technologyreview.com)
- These photoreceptors carry signal impulses along nerve cells to form the optic nerve. (medicalnewstoday.com)
- Traditionally, visual information has been seen as ascending through a hierarchy of cortical areas, with cells at each successive stage processing inputs from increasingly larger regions of space. (jneurosci.org)
- Sensory information is relayed to cortex via thalamocortical inputs, which excite both excitatory pyramidal neurons and inhibitory interneurons within layer 4, forming a 'feedforward' circuit. (elifesciences.org)
- We perceive the world as stable and composed of discrete objects even though auditory and visual inputs are often ambiguous owing to spatial and temporal occluders and changes in the conditions of observation. (royalsocietypublishing.org)
- Specifically, it allowed us to examine the effects of an interrupted processing of half of the retinal output (i.e., visual information coming from the left visual field) and the deprivation of interhemispheric inputs on the visual field map (VFM) properties. (hindawi.com)
- Each labelled neuron then transports the barcode into its own axonal processes where they can be read out by high throughout sequencing of a dissected target area to determine the projection targets of that specific neuron to higher visual areas. (ucl.ac.uk)
- Our data indicate that astrocytes expressing mutant HRAS dysregulate cortical maturation during development as shown by abnormal extracellular matrix remodeling and implicate excessive astrocyte-to-neuron signaling as a possible drug target for treating mental impairment and enhancing neuroplasticity. (sciencemag.org)
- A wireless neural prosthetic device for a primary auditory cortex of a patient includes either a speech processor or a stimulating device for receiving and processing information and a wireless electrode arranged in the primary auditory cortex having a plurality of electrical contacts. (google.com)
- The electrode can be arranged in the patient's primary auditory cortex and each of the plurality of electrical contacts independently outputs electrical discharges in accordance with the processed electrical signals. (google.com)
- circuitry electrically coupled to said plurality of electrical contacts for receiving said processed electrical signals and for selectively outputting electrical discharges to said plurality of electrical contacts in accordance with said processed electrical signals. (google.com)
- 10. The apparatus as claimed in claim 1, further comprising a transmitting antenna coupled to said circuitry, wherein said circuitry receives neural activity signals from said plurality of electrical contacts and transforms said neural activity signals into electromagnetic waves with said neural activity signals modulated thereon and said transmitting antenna transmits said electromagnetic waves. (google.com)
- A neural prosthetic device for an auditory cortex of a patient has a support arranged in the auditory cortex with a plurality of electrical contacts and is connected to a speech processor for receiving and processing audio information and outputting processed electrical signals. (google.co.uk)
- Each of the plurality of electrical contacts independently outputs electrical discharges in accordance with the processed electrical signals. (google.co.uk)
- As we interact with our environment, the features of objects in the visual scene are not consistently present on the retina. (jneurosci.org)
- Once the light has been processed by the photoreceptors an electrochemical signal is then passed via a network of neurons to the ganglion cells further back in the retina. (interaction-design.org)
- Visual processing and, ultimately, visual fields begin in the retina. (medscape.com)
- Although it is tissue-paper thin, the natural retina contains a complex layering of neurons that work together to convert light into electrical nerve signals. (technologyreview.com)
- In a bio-inspired context retinal flow is the change of structured patterns of light on the retina that lead to an impression of movement of the visual imagery projected onto the retina. (scholarpedia.org)
- Visual information enters through your eyes where the retina converts light into electrical signals. (thenakedscientists.com)
- Stimulate the remaining healthy nerve cells in the retina, and sensations of light can be created in the visual field. (wired.co.uk)
- Composition and topographic organization of signals sent from the frontal eye ffield to the superior colliculus. (psu.edu)
- In order to obtain in vivo proton MR spectra two distinct voxels of interests (VOIs) corresponding to visual cortex (5x2x1.2 mm 3 ) and frontal cortex (4x2x1.5mm 3 ) were precisely positioned basing on T2-weighted images. (arvojournals.org)
- 0.001) but not in the frontal cortex (1.084±0.021 vs. 1.169±0.033, ns. (arvojournals.org)
- The spatial scale of feedback circuits from extrastriate cortex to V1 is, instead, commensurate with the full spatial range of center-surround interactions. (jneurosci.org)
- Using artificial cell-cell signalling circuits, we generated robust multi-layered self-organizing structures displaying cell type divergence, symmetry breaking, and regeneration upon injury. (hfsp.org)
- Interestingly, acute episodes of visual experience do not affect the density or distribution of estrogen-associated circuits. (pubmedcentralcanada.ca)
- circuits connected to visual cortex's neurons]. (bio.net)
- Whether cortical circuits contribute to surround suppression or whether the phenomenon is entirely relayed from earlier stages of visual processing is debated. (biomedsearch.com)
- These data suggest that Arc is required for the experience-dependent processes that normally establish and modify synaptic connections in visual cortex. (nih.gov)
- Here, we show that ablating β-catenin in excitatory neurons of the adult visual cortex does not cause the same synaptic deficits previously observed during development. (deepdyve.com)
- We therefore studied the synaptic function of β-catenin in the adult cortex. (deepdyve.com)
- Orientation selectivity in visual cortex is not simply the result of linear input summation. (nature.com)
- However, to date, the relationship of orientation architecture to the encoding of multiple elemental aspects of visual contours is still unknown. (sciencemag.org)
- We suggest that these zones subserve computation of distinct aspects of visual contours and propose a novel tripartite pinwheel-centered view of an orientation hypercolumn. (sciencemag.org)
- Bauer R, Fischer WH (1987) Continuity or incontinuity of orientation columns in visual cortex: a critical evaluation of published and unpublished data. (springer.com)
- Relationship between contrast adaptation and orientation tuning in V1 and V2 of cat visual cortex. (semanticscholar.org)
- However, behavioral research demonstrates that not all visual tasks suffer such capacity limits: The costs of divided attention are minimal when the task and stimulus are simple, such as when searching for a target defined by orientation or contrast. (arvojournals.org)
- Objective: Vestibular signals are involved in higher cortical functions like spatial orientation and its disorders. (uni-muenchen.de)
- We found that camouflaged motion at low speed was processed as a direction signal by both direction- and orientation-selective neurons, whereas at high-speed camouflaged motion was encoded as a motion-streak signal primarily by orientation-selective neurons. (royalsocietypublishing.org)
- Path dissociation of visual signals entering the cortex: disparity, contour orientation and position. (berkeley.edu)
- In the present study, we showed a postnatal sensitive period profile for the modifiability of orientation selectivity in the visual cortex of kittens reared with head-mounted goggles for stable single-orientation exposure. (plos.org)
- In addition, head-mounted cylindrical-lens-fitted goggles provide an efficient tool for restricting visual experience to a single orientation. (plos.org)
- It has been shown that infusion of an NMDA receptor antagonist to the visual cortex suppresses the expression of orientation selectivity , . (plos.org)
- It is further expected that NMDA-receptor-mediated long-term potentiation (LTP) at synapses to visual cortical neurons optimally activated by the exposed orientation is involved in the over-representation of that orientation. (plos.org)
- In both experiments reliable changes in motor cortex excitability were evident under low-load conditions, but this effect was eliminated under high-attentional load. (ant-neuro.com)
- In a third experiment we investigated whether the attentional task was associated with ongoing changes in the excitability of motor cortex, but found no difference in evoked potentials across the levels of attentional load. (ant-neuro.com)
- Hence, modularity may be functionally defined, or defined solely on the differing responsiveness of adjacent regions of cortex. (frontiersin.org)
- Eckhorn R, Bauer R, Brosch M, Jordan W, Kruse W, Munk M (1988b) Functionally related modules of cat visual cortex show stimulus-evoked coherent oscillations: A multiple electrode study. (springer.com)
- Damage to the visual system can result in (a partial) loss of vision, in response to which the visual system may functionally reorganize. (hindawi.com)
- Thus, feedforward and feedback E-I ratios can be independently tuned by visual experience, and enhanced feedback inhibition is the primary driving force behind loss of visual responsiveness. (elifesciences.org)
- Acetylcholine-induced inhibition in the cat visual cortex is mediated by a GABAergic mechanism. (semanticscholar.org)
- He postulated that the purpose of the visual system is to provide a representation of what is present in the outside world. (royalsocietypublishing.org)
- In this paper, a visual attention model uniting hyperparameter sparse representation with energy distribution optimization is proposed for analyzing saliency and detecting ROIs in remote sensing images. (mdpi.com)
- cone cells handle the high acuity visual tasks such as reading and color vision. (interaction-design.org)
- Visual Acuity: Information theory, retinal image structure and resolution thresholds. (berkeley.edu)
- Heightened attention-vigilance-increases visual acuity. (dana.org)
- After 12 years in the lab, Robert Greenberg has brought a viable retinal prosthesis to market -- and returned at least some visual acuity to sightless patients. (wired.co.uk)