Visual Cortex: Area of the OCCIPITAL LOBE concerned with the processing of visual information relayed via VISUAL PATHWAYS.Motor Neurons: Neurons which activate MUSCLE CELLS.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.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.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.Visual Perception: The selecting and organizing of visual stimuli based on the individual's past experience.Evoked Potentials, Visual: The electric response evoked in the cerebral cortex by visual stimulation or stimulation of the visual pathways.Visual Fields: The total area or space visible in a person's peripheral vision with the eye looking straightforward.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.Orientation: Awareness of oneself in relation to time, place and person.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)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.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.Brain Mapping: Imaging techniques used to colocalize sites of brain functions or physiological activity with brain structures.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.Vision, Monocular: Images seen by one eye.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.Motor Neuron Disease: Diseases characterized by a selective degeneration of the motor neurons of the spinal cord, brainstem, or motor cortex. Clinical subtypes are distinguished by the major site of degeneration. In AMYOTROPHIC LATERAL SCLEROSIS there is involvement of upper, lower, and brainstem motor neurons. In progressive muscular atrophy and related syndromes (see MUSCULAR ATROPHY, SPINAL) the motor neurons in the spinal cord are primarily affected. With progressive bulbar palsy (BULBAR PALSY, PROGRESSIVE), the initial degeneration occurs in the brainstem. In primary lateral sclerosis, the cortical neurons are affected in isolation. (Adams et al., Principles of Neurology, 6th ed, p1089)Action Potentials: Abrupt changes in the membrane potential that sweep along the CELL MEMBRANE of excitable cells in response to excitation stimuli.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.Sensory Deprivation: The absence or restriction of the usual external sensory stimuli to which the individual responds.Pattern Recognition, Visual: Mental process to visually perceive a critical number of facts (the pattern), such as characters, shapes, displays, or designs.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.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.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.Vision, Binocular: The blending of separate images seen by each eye into one composite image.Neuronal Plasticity: The capacity of the NERVOUS SYSTEM to change its reactivity as the result of successive activations.Reaction Time: The time from the onset of a stimulus until a response is observed.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.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.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.Space Perception: The awareness of the spatial properties of objects; includes physical space.Neural Inhibition: The function of opposing or restraining the excitation of neurons or their target excitable cells.Neurons, Afferent: Neurons which conduct NERVE IMPULSES to the CENTRAL NERVOUS SYSTEM.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.Motion Perception: The real or apparent movement of objects through the visual field.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.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.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.Attention: Focusing on certain aspects of current experience to the exclusion of others. It is the act of heeding or taking notice or concentrating.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.Fixation, Ocular: The positioning and accommodation of eyes that allows the image to be brought into place on the FOVEA CENTRALIS of each eye.Survival of Motor Neuron 1 Protein: A SMN complex protein that is essential for the function of the SMN protein complex. In humans the protein is encoded by a single gene found near the inversion telomere of a large inverted region of CHROMOSOME 5. Mutations in the gene coding for survival of motor neuron 1 protein may result in SPINAL MUSCULAR ATROPHIES OF CHILDHOOD.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.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.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.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.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.Form Perception: The sensory discrimination of a pattern shape or outline.Neural Pathways: Neural tracts connecting one part of the nervous system with another.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)Time Factors: Elements of limited time intervals, contributing to particular results or situations.Auditory Cortex: The region of the cerebral cortex that receives the auditory radiation from the MEDIAL GENICULATE BODY.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.Macaca radiata: A species of macaque monkey that mainly inhabits the forest of southern India. They are also called bonnet macaques or bonnet monkeys.Psychomotor Performance: The coordination of a sensory or ideational (cognitive) process and a motor activity.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.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.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.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.Axons: Nerve fibers that are capable of rapidly conducting impulses away from the neuron cell body.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.Evoked Potentials, Motor: The electrical response evoked in a muscle or motor nerve by electrical or magnetic stimulation. Common methods of stimulation are by transcranial electrical and TRANSCRANIAL MAGNETIC STIMULATION. It is often used for monitoring during neurosurgery.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.Eye Movements: Voluntary or reflex-controlled movements of the eye.Electric Stimulation: Use of electric potential or currents to elicit biological responses.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.Dominance, Cerebral: Dominance of one cerebral hemisphere over the other in cerebral functions.Ocular Physiological Phenomena: Processes and properties of the EYE as a whole or of any of its parts.Depth Perception: Perception of three-dimensionality.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.Critical Period (Psychology): A specific stage in animal and human development during which certain types of behavior normally are shaped and molded for life.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.Sensory Thresholds: The minimum amount of stimulus energy necessary to elicit a sensory response.Survival of Motor Neuron 2 Protein: A SMN complex protein that is closely-related to SURVIVAL OF MOTOR NEURON 1 PROTEIN. In humans, the protein is encoded by an often duplicated gene found near the inversion centromere of a large inverted region of CHROMOSOME 5.Discrimination (Psychology): Differential response to different stimuli.Optical Illusions: An illusion of vision usually affecting spatial relations.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.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.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.Thalamus: Paired bodies containing mostly GRAY MATTER and forming part of the lateral wall of the THIRD VENTRICLE of the brain.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.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.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.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)Spinal Cord: A cylindrical column of tissue that lies within the vertebral canal. It is composed of WHITE MATTER and GRAY MATTER.Amyotrophic Lateral Sclerosis: A degenerative disorder affecting upper MOTOR NEURONS in the brain and lower motor neurons in the brain stem and SPINAL CORD. Disease onset is usually after the age of 50 and the process is usually fatal within 3 to 6 years. Clinical manifestations include progressive weakness, atrophy, FASCICULATION, hyperreflexia, DYSARTHRIA, dysphagia, and eventual paralysis of respiratory function. Pathologic features include the replacement of motor neurons with fibrous ASTROCYTES and atrophy of anterior SPINAL NERVE ROOTS and corticospinal tracts. (From Adams et al., Principles of Neurology, 6th ed, pp1089-94)Illusions: The misinterpretation of a real external, sensory experience.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.Wakefulness: A state in which there is an enhanced potential for sensitivity and an efficient responsiveness to external stimuli.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.Callithrix: A genus of the subfamily CALLITRICHINAE occurring in forests of Brazil and Bolivia and containing seventeen species.Dendrites: Extensions of the nerve cell body. They are short and branched and receive stimuli from other NEURONS.Cues: Signals for an action; that specific portion of a perceptual field or pattern of stimuli to which a subject has learned to respond.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.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.Eye Enucleation: The surgical removal of the eyeball leaving the eye muscles and remaining orbital contents intact.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).Animals, Newborn: Refers to animals in the period of time just after birth.Adaptation, Physiological: The non-genetic biological changes of an organism in response to challenges in its ENVIRONMENT.Signal Processing, Computer-Assisted: Computer-assisted processing of electric, ultrasonic, or electronic signals to interpret function and activity.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.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.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.Learning: Relatively permanent change in behavior that is the result of past experience or practice. The concept includes the acquisition of knowledge.Motor Activity: The physical activity of a human or an animal as a behavioral phenomenon.Nerve Tissue ProteinsMuscular Atrophy, Spinal: A group of disorders marked by progressive degeneration of motor neurons in the spinal cord resulting in weakness and muscular atrophy, usually without evidence of injury to the corticospinal tracts. Diseases in this category include Werdnig-Hoffmann disease and later onset SPINAL MUSCULAR ATROPHIES OF CHILDHOOD, most of which are hereditary. (Adams et al., Principles of Neurology, 6th ed, p1089)PrimatesSize Perception: The sensory interpretation of the dimensions of objects.Parvalbumins: Low molecular weight, calcium binding muscle proteins. Their physiological function is possibly related to the contractile process.Acoustic Stimulation: Use of sound to elicit a response in 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.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.Saccades: An abrupt voluntary shift in ocular fixation from one point to another, as occurs in reading.Excitatory 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.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.gamma-Aminobutyric Acid: The most common inhibitory neurotransmitter in the central nervous system.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.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.Sensory Receptor Cells: Specialized afferent neurons capable of transducing sensory stimuli into NERVE IMPULSES to be transmitted to the CENTRAL NERVOUS SYSTEM. Sometimes sensory receptors for external stimuli are called exteroceptors; for internal stimuli are called interoceptors and proprioceptors.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.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.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)Computer Simulation: Computer-based representation of physical systems and phenomena such as chemical processes.Cortical Synchronization: EEG phase synchronization of the cortical brain region (CEREBRAL CORTEX).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)Darkness: The absence of light.Mice, Inbred C57BLAwareness: 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.Aotidae: A family of the New World monkeys inhabiting the forests of South and Central America. There is a single genus and several species occurring in this family, including AOTUS TRIVIRGATUS (Northern night monkeys).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.Afferent Pathways: Nerve structures through which impulses are conducted from a peripheral part toward a nerve center.Cell Count: The number of CELLS of a specific kind, usually measured per unit volume or area of sample.Electron 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.Brain Waves: Wave-like oscillations of electric potential between parts of the brain recorded by EEG.Neural Networks (Computer): A computer architecture, implementable in either hardware or software, modeled after biological neural networks. Like the biological system in which the processing capability is a result of the interconnection strengths between arrays of nonlinear processing nodes, computerized neural networks, often called perceptrons or multilayer connectionist models, consist of neuron-like units. A homogeneous group of units makes up a layer. These networks are good at pattern recognition. They are adaptive, performing tasks by example, and thus are better for decision-making than are linear learning machines or cluster analysis. They do not require explicit programming.Neuropil: A dense intricate feltwork of interwoven fine glial processes, fibrils, synaptic terminals, axons, and dendrites interspersed among the nerve cells in the gray matter of the central nervous system.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.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).Iontophoresis: Therapeutic introduction of ions of soluble salts into tissues by means of electric current. In medical literature it is commonly used to indicate the process of increasing the penetration of drugs into surface tissues by the application of electric current. It has nothing to do with ION EXCHANGE; AIR IONIZATION nor PHONOPHORESIS, none of which requires current.Immunohistochemistry: Histochemical localization of immunoreactive substances using labeled antibodies as reagents.SMN Complex Proteins: A complex of proteins that assemble the SNRNP CORE PROTEINS into a core structure that surrounds a highly conserved RNA sequence found in SMALL NUCLEAR RNA. They are found localized in the GEMINI OF COILED BODIES and in the CYTOPLASM. The SMN complex is named after the Survival of Motor Neuron Complex Protein 1, which is a critical component of the complex.Behavior, Animal: The observable response an animal makes to any situation.Color: The visually perceived property of objects created by absorption or reflection of specific wavelengths of light.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)Algorithms: A procedure consisting of a sequence of algebraic formulas and/or logical steps to calculate or determine a given task.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.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.Consciousness: Sense of awareness of self and of the environment.Aging: The gradual irreversible changes in structure and function of an organism that occur as a result of the passage of time.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)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.Information Theory: An interdisciplinary study dealing with the transmission of messages or signals, or the communication of information. Information theory does not directly deal with meaning or content, but with physical representations that have meaning or content. It overlaps considerably with communication theory and CYBERNETICS.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.Discrimination Learning: Learning that is manifested in the ability to respond differentially to various stimuli.Membrane Potentials: The voltage differences across a membrane. For cellular membranes they are computed by subtracting the voltage measured outside the membrane from the voltage measured inside the membrane. They result from differences of inside versus outside concentration of potassium, sodium, chloride, and other ions across cells' or ORGANELLES membranes. For excitable cells, the resting membrane potentials range between -30 and -100 millivolts. Physical, chemical, or electrical stimuli can make a membrane potential more negative (hyperpolarization), or less negative (depolarization).Auditory Perception: The process whereby auditory stimuli are selected, organized, and interpreted by the organism.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.Presynaptic Terminals: The distal terminations of axons which are specialized for the release of neurotransmitters. Also included are varicosities along the course of axons which have similar specializations and also release transmitters. Presynaptic terminals in both the central and peripheral nervous systems are included.Cathode Ray Tube: A vacuum tube equipped with an electron emitting CATHODE and a fluorescent screen which emits visible light when excited by the cathode ray. Cathode ray tubes are used as imaging devises for TELEVISIONS; COMPUTER TERMINALS; TEXT TELECOMMUNICATION DEVICES; oscilloscopes; and other DATA DISPLAY devices.Nerve Degeneration: Loss of functional activity and trophic degeneration of nerve axons and their terminal arborizations following the destruction of their cells of origin or interruption of their continuity with these cells. The pathology is characteristic of neurodegenerative diseases. Often the process of nerve degeneration is studied in research on neuroanatomical localization and correlation of the neurophysiology of neural pathways.Frontal Lobe: The part of the cerebral hemisphere anterior to the central sulcus, and anterior and superior to the lateral sulcus.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).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.Retinal Cone Photoreceptor Cells: Photosensitive afferent neurons located primarily within the FOVEA CENTRALIS of the MACULA LUTEA. There are three major types of cone cells (red, blue, and green) whose photopigments have different spectral sensitivity curves. Retinal cone cells operate in daylight vision (at photopic intensities) providing color recognition and central visual acuity.Molecular Motor Proteins: Proteins that are involved in or cause CELL MOVEMENT such as the rotary structures (flagellar motor) or the structures whose movement is directed along cytoskeletal filaments (MYOSIN; KINESIN; and DYNEIN motor families).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.Green Fluorescent Proteins: Protein analogs and derivatives of the Aequorea victoria green fluorescent protein that emit light (FLUORESCENCE) when excited with ULTRAVIOLET RAYS. They are used in REPORTER GENES in doing GENETIC TECHNIQUES. Numerous mutants have been made to emit other colors or be sensitive to pH.Macaca nemestrina: A species of the genus MACACA which inhabits Malaya, Sumatra, and Borneo. It is one of the most arboreal species of Macaca. The tail is short and untwisted.Light: That portion of the electromagnetic spectrum in the visible, ultraviolet, and infrared range.Mice, Transgenic: Laboratory mice that have been produced from a genetically manipulated EGG or EMBRYO, MAMMALIAN.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.)Data Interpretation, Statistical: Application of statistical procedures to analyze specific observed or assumed facts from a particular study.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.Electrodes: Electric conductors through which electric currents enter or leave a medium, whether it be an electrolytic solution, solid, molten mass, gas, or vacuum.Perceptual Masking: The interference of one perceptual stimulus with another causing a decrease or lessening in perceptual effectiveness.Ganglia, Invertebrate: Clusters of neuronal cell bodies in invertebrates. Invertebrate ganglia may also contain neuronal processes and non-neuronal supporting cells. Many invertebrate ganglia are favorable subjects for research because they have small numbers of functional neuronal types which can be identified from one animal to another.Neuromuscular Diseases: A general term encompassing lower MOTOR NEURON DISEASE; PERIPHERAL NERVOUS SYSTEM DISEASES; and certain MUSCULAR DISEASES. Manifestations include MUSCLE WEAKNESS; FASCICULATION; muscle ATROPHY; SPASM; MYOKYMIA; MUSCLE HYPERTONIA, myalgias, and MUSCLE HYPOTONIA.Histocytochemistry: Study of intracellular distribution of chemicals, reaction sites, enzymes, etc., by means of staining reactions, radioactive isotope uptake, selective metal distribution in electron microscopy, or other methods.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)Cerebrovascular Circulation: The circulation of blood through the BLOOD VESSELS of the BRAIN.GABAergic Neurons: Neurons whose primary neurotransmitter is GAMMA-AMINOBUTYRIC ACID.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.Visual Field Tests: Method of measuring and mapping the scope of vision, from central to peripheral of each eye.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.Hippocampus: A curved elevation of GRAY MATTER extending the entire length of the floor of the TEMPORAL HORN of the LATERAL VENTRICLE (see also TEMPORAL LOBE). The hippocampus proper, subiculum, and DENTATE GYRUS constitute the hippocampal formation. Sometimes authors include the ENTORHINAL CORTEX in the hippocampal formation.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.Neurofilament Proteins: Type III intermediate filament proteins that assemble into neurofilaments, the major cytoskeletal element in nerve axons and dendrites. They consist of three distinct polypeptides, the neurofilament triplet. Types I, II, and IV intermediate filament proteins form other cytoskeletal elements such as keratins and lamins. It appears that the metabolism of neurofilaments is disturbed in Alzheimer's disease, as indicated by the presence of neurofilament epitopes in the neurofibrillary tangles, as well as by the severe reduction of the expression of the gene for the light neurofilament subunit of the neurofilament triplet in brains of Alzheimer's patients. (Can J Neurol Sci 1990 Aug;17(3):302)Cells, Cultured: Cells propagated in vitro in special media conducive to their growth. Cultured cells are used to study developmental, morphologic, metabolic, physiologic, and genetic processes, among others.Cognition: Intellectual or mental process whereby an organism obtains knowledge.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.Physical Stimulation: Act of eliciting a response from a person or organism through physical contact.Periodicity: The tendency of a phenomenon to recur at regular intervals; in biological systems, the recurrence of certain activities (including hormonal, cellular, neural) may be annual, seasonal, monthly, daily, or more frequently (ultradian).Cholinergic Neurons: Neurons whose primary neurotransmitter is ACETYLCHOLINE.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 4.1.1.15.Thalamic Nuclei: Several groups of nuclei in the thalamus that serve as the major relay centers for sensory impulses in the brain.Anesthesia: A state characterized by loss of feeling or sensation. This depression of nerve function is usually the result of pharmacologic action and is induced to allow performance of surgery or other painful procedures.Reward: An object or a situation that can serve to reinforce a response, to satisfy a motive, or to afford pleasure.Disease Models, Animal: Naturally occurring or experimentally induced animal diseases with pathological processes sufficiently similar to those of human diseases. They are used as study models for human diseases.Wheat Germ Agglutinin-Horseradish Peroxidase Conjugate: The lectin wheatgerm agglutinin conjugated to the enzyme HORSERADISH PEROXIDASE. It is widely used for tracing neural pathways.
  • Ashe J, Georgopoulos AP (1994) Movement parameters and neural activity in motor cortex and area 5. (springer.com)
  • The neural response range of these neurons is increased and the response latency is reduced. (physiology.org)
  • For example, in most people, the dominant hemisphere for language is the left hemisphere, where most of the neural processing takes place for speech comprehension, the formation of thoughts into speech, and the generation of motor output for language communication. (newworldencyclopedia.org)
  • These systems translate neural activity from the brain into control signals for prosthetic devices, which can assist people with paralysis by restoring lost motor functions. (stanford.edu)
  • The spatial pattern of results could be captured by a model that involves interactions, on a logarithmic map of visual space, between two loci of neural activity that encode the gaze shift vector and visual stimulus position relative to the fovea. (arvojournals.org)
  • The movement-related findings were unexpected since vision tends to be thought of as a feed-forward computation system in which visual information enters through the retina and travels on neural circuits that operate on a one-way path, processing the information piece by piece. (genengnews.com)
  • The team also noticed that the neural patterns in the visual cortex that were firing during movement differed in the dark and light, meaning they weren't directly connected. (genengnews.com)
  • These findings reveal that threat tunes neural processing in fast, selective, yet attention-independent fashion in sensory and motor systems, for different adaptive purposes. (elifesciences.org)
  • Here, we investigate the dimensionality of neural ensembles from the insular cortex of alert rats during periods of `ongoing' (spontaneous) and stimulus-evoked activity. (aps.org)
  • To our knowledge, this is the first mechanistic model of neural dimensionality in cortex during both spontaneous and evoked activity. (aps.org)
  • At this juncture in our exploration of motor control, let's focus on one of the best studied paradigms for understanding the neural control of movement: the eye movement system. (coursera.org)
  • This paper focuses on the neurodynamical research of a small neural network that consists of 25 neurons. (hindawi.com)
  • In fact, we know little about expressions of neuron membrane potentials and interactions between neural networks, especially the relationship between neural coding modes and cognitive behaviors. (hindawi.com)
  • So our purpose is to try to understand the inner connection between the up and down transitions of a single neuron and that of neural network. (hindawi.com)
  • Then, they used a visual paradigm designed to elicit neural responses with differing spatial frequencies in the brain and examined how the new super-Nyquist density EEG performed, revealing that the new configuration captured more neural information than standard Nyquist density EEG. (healthcanal.com)
  • The subtle patterns of neural activity uncovered by the new super-Nyquist EEG were closely related to a model of primary visual cortex. (healthcanal.com)
  • Motor imagery and action observation facilitate motor recovery of patients because both the motor imagery and the action observation share the activation of cortical neural networks implicated in movement execution. (intechopen.com)
  • This chapter reviews the neural mechanisms and clinical studies of motor imagery and action observation and discusses the applications in physical therapy. (intechopen.com)
  • reported the neural network of motor imagery using ALE meta‐analysis [ 5 ]. (intechopen.com)
  • Our main aim is to understand the cellular bases of motor behaviour with a focus on the mechanisms underlying selection of behaviour and the neural bases of in particular locomotion. (ki.se)
  • To gain a reward, the rats learned to produce arbitrary patterns of neural activity unrelated to visual input in order to control a BMI, highlighting the power of neuroplasticity and the flexibility of the brain. (myscience.org)
  • The cerebral cortex (plural cortices ), also known as the cerebral mantle , is the outer layer of neural tissue of the cerebrum of the brain in humans and other mammals . (wikipedia.org)
  • The cerebral cortex is the largest site of neural integration in the central nervous system . (wikipedia.org)
  • The cerebral cortex is folded in a way that allows a large surface area of neural tissue to fit within the confines of the neurocranium . (wikipedia.org)
  • Anisha constructed naive Bayes classifiers to quantify the impact of postural vs visual changes in workspace and found that neural tuning change is driven by postural, not visual changes. (cmu.edu)
  • A group of researchers led by Professor KITAZAWA Shigeru (Dynamic Brain Network Laboratory, Graduate School of Frontier Biosciences, Osaka University) and Researcher INOUE Masato (Center for Information and Neural Networks (CiNet), National Institute of Information and Communications Technology) clarified that information about direction and size of errors in reaching movements appeared in the motor cortex. (osaka-u.ac.jp)
  • The visual system has been a long-standing model for studying the precise wiring of neural circuits. (deepdyve.com)
  • Carmena JM, Lebedev MA, Henriquez CS, Nicolelis MAL (2005) Stable ensemble performance with single-neuron variability during reaching movements in primates. (springer.com)
  • Journal Article] Different cortical projections from three subdivisions of the rat lateral posterior thalamic nucleus : a single-neuron tracing study with viral vectors. (nii.ac.jp)
  • The advent of single neuron electrophysiological recordings in alert monkeys in the last 50 years, accompanied by more precise lesion and stimulation experiments, have helped to clarify the function of the FEF in motor, perceptual, and cognitive processes. (scholarpedia.org)
  • Therefore, the up and down states of single neuron reflect distinct global cortical states, which resemble slow-wave and rapid-eye-movement sleep, respectively [ 20 - 22 ]. (hindawi.com)
  • Here, one single neuron affects the whole network status by impacting other coupling neurons. (hindawi.com)
  • We have started our research on a single neuron, studied the electrophysiological phenomenon of status transitions, and obtained the bistability and spontaneity that is similar to experiment observation. (hindawi.com)
  • Thus, the LGN employs at least three modes of visual input integration, each exhibiting different degrees of specialization (Rompani et al, Neuron, 2017). (europa.eu)
  • He and Neely, who completed his Ph.D. with Carmena in 2017, tested these limits by trying to train visual neurons, which normally interpret input from the eyes but don't control any physical action, to act like motor neurons that control muscles. (myscience.org)
  • This unit covers the surface anatomy of the human brain, its internal structure, and the overall organization of sensory and motor systems in the brainstem and spinal cord. (coursera.org)
  • The cerebral cortex informs the spinal cord about the desired voluntary movements both directly via the corticospinal tract (CST) and/or indirectly via the corticorubral, corticotectal and the corticobulbar (corticoreticular) projections which connect the cerebral cortex with different levels of the brainstem that in turn projects to the spinal cord ( Lemon, 2008 ). (frontiersin.org)
  • In the CNS, neurons are topographically organized either as aggregates (nuclei, ganglia) or as elongated columns or layers (such as the intermediolateral gray column of the spinal cord or the six-layered cerebral cortex). (humpath.com)
  • This allows a given DPM to participate in the computations taking place in other areas of cerebral cortex or in the brainstem or spinal cord. (royalsocietypublishing.org)
  • A summary of brain structure and function reveals the importance of the prefrontal cortex (PFC) to creative thinking. (dana.org)
  • The pontine micturition center controls the bladder state between storage and voiding by communicating with other brain regions including the medial prefrontal cortex, hypothalamus, and periaqueductal gray ( Fig. 1 ). (einj.org)
  • They used two paradigms that differed widely in musical complexity and found that improvisation was consistently characterized by a dissociated pattern of activity in the prefrontal cortex 17 . (nature.com)
  • The Frontal Eye Field (FEF) is a region of primate prefrontal cortex defined as the area in which low-current electrical stimulation evokes saccadic eye movements . (scholarpedia.org)
  • 1952). In the modern era of brain research this small sliver of the prefrontal cortex (PFC) known as the Frontal Eye Field (FEF) is localized to the area of PFC from which short-latency saccadic eye movements ( saccades ) can be evoked reliably by electrical stimulation using relatively low electrical currents (Robinson and Fuchs, 1969). (scholarpedia.org)
  • Cell type-specific three-dimensional structure of thalamocortical circuits in a column of rat vibrissal cortex. (nature.com)
  • We chose the blowfly as a model system because the cells and circuits that process visual motion information and contribute to motor control are exceptionally well studied (reviewed in Krapp and Wicklein 2008 ). (physiology.org)
  • A guiding hypothesis is that the plasticity of neurotransmission plays a major part in controlling the input-output relation of sensory circuits, regulating the tuning and sensitivity of neurons to allow adaptation or sensitization to particular features of the input. (sussex.ac.uk)
  • The findings suggest that image-processing circuits in the primary visual cortex not only are more active when animals move, but that they receive signals from a movement-controlling region of the brain that is independent from the region that processes what the animal is looking at. (genengnews.com)
  • The optic tectum contains motor circuits for the control of eye and orienting/evasive movements and receives visual input arranged in a retinotopic map. (ki.se)
  • Define how the visual cortex, the spinal limbed locomotor circuits, and the cortical hemispheric dominance on handedness and chest wall respiratory function influence lower extremity sense, support and stability during forward locomotor movement. (posturalrestoration.com)
  • Motor cortical circuits have been hypothesized to provide execution errors that drive adaptation, but human imaging studies to date have reported that execution errors are encoded in parietal association areas. (osaka-u.ac.jp)
  • The results indicate for the first time that motor cortical circuits provide error signals that drive trial-by-trial adaptation in reaching movements. (osaka-u.ac.jp)
  • 26. A Cerebellar circuits decussate twice before reaching the lower motor neurons. (brainaacn.org)
  • Individual neurons encoded task-specific responses, but every brain area contained neurons with different types of response. (sciencemag.org)
  • He arbitrarily routed the electrical activity recorded by the electrodes - representing the spiking of several individual neurons - to a device that raised or lowered the pitch of an audible tone depending on which neurons were active. (myscience.org)
  • Georgopoulos AP, Kalaska JF, Caminiti R, Massey JT (1982) On the relations between the direction of two-dimensional arm movements and cell discharge in primate motor cortex. (springer.com)
  • Correct binocular eye alignment and conjugate gaze are critical components for normal development of the primate visual system. (arvojournals.org)
  • In areas MSTD and VIP of primate multi-sensory cortex, it has been found that some neurons exhibit invariant head direction tuning regardless of sensory modalities, i.e., each of these congruent cells is tuned to a specific heading direction of the animal irrespective whether the head direction cue is coming from the visual system or the vestibular system. (cmu.edu)
  • These drives are established through the activity of populations of hypothalamic neurons that sense physiological variables and relay this information to other parts of the brain. (sciencemag.org)
  • Furthermore, the fetal graft may produce trophic factors or signaling cues, which are present in the brain only at early developmental stages, and should reactivate neurotropic processes in a 'dormant' host neuron populations. (utah.edu)
  • How is it that groups of neurons dispersed through the brain interact to generate complex behaviors? (sciencemag.org)
  • Synfire chains-networks in which groups of neurons are connected via excitatory synapses into a unidirectional chain-are thought to underlie the generation of such sequences. (yale.edu)
  • We arbitrarily hijacked small groups of neurons in the visual cortex and virtually re-routed their output to make them control a brain-machine interface, or BMI," said Jose Carmena, senior author of a paper about the development that will appear March 1 in the journal Neuron . (myscience.org)
  • In larger mammals, including humans, the surface of the cerebral cortex folds to create gyri (ridges) and sulci (furrows) which increase the surface area. (wikipedia.org)
  • The surface of the cerebral cortex is highly convoluted in large mammals, with the folds and grooves allowing a much greater surface area in a confined space as in the skull. (newworldencyclopedia.org)
  • An inflammatory disorder of the facial nerve in man resulting in lower motor neuron facial muscle weakness, hyperacusis, impaired taste and impaired lacrimation. (neuropetvet.com)
  • In other cases, namely the urban pattern in which the lower motor neuron (UMN) facial weakness caused by a cold, mottled appearance and mild extrapyramidal or parkinsonian side effects. (cide.edu)
  • New methods to reactivate the thalamic neurons by channeling visual information directly to these neurons may help to restore some visual capability after the loss of optic nerve fibers. (europa.eu)
  • Similarities in neocortical circuit organization across areas and species suggest a common strategy to process diverse types of information, including sensation from diverse modalities, motor control and higher cognitive processes. (nature.com)
  • 12 A primary difference between our brains and those of other animals is our capacity to engage in cognitive abilities such as reasoning, representation, association, working memory, and self-reflection. (dana.org)
  • It has been suggested that right handedness evolved in the context of escalating motor and cognitive demands related to tool use. (diva-portal.org)
  • 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)
  • Motor imagery is a cognitive process in which a subject only imagines completing a movement, without tensing any muscles ( Figure 1(a) ) [ 2 ]. (intechopen.com)
  • Although action observation was associated with increases in corticospinal excitability (reflecting putative human mirror neuron activity), there was no effect of visual perspective. (frontiersin.org)
  • These findings are discussed in the context of contemporary theories of mirror neuron ontogeny, including models concerning associative learning and evolutionary adaptation. (frontiersin.org)
  • an analogous "mirror neuron system" (MNS) has since been established in humans ( Rizzolatti and Fabbri-Destro, 2010 ). (frontiersin.org)
  • Given a proposed link to interpersonal understanding, there has been some interest in the degree to which a mirror neuron response is modulated by the perspective from which an action is presented (e.g., self/egocentric vs. other/allocentric perspective). (frontiersin.org)
  • The cortical mirror system reflects the cortical motor system: comment on "Grasping synergies: a motor-control approach to the mirror neuron mechanism" by A. D'Ausilio et al. (nottingham.ac.uk)
  • We are particularly interested in how activity in two particular subtype of interneuron,the VIPs and SSTs, alters responsivity of principal neurons according to the recent history of stimulation. (sussex.ac.uk)
  • In primates, inspection of a visual scene is typically interrupted by frequent gaze shifts, occurring at an average rate of three to five times per second. (arvojournals.org)
  • Humans are largely visual animals and require that images of objects of interest must be held steadily on the fovea, a region on the retina that allows for high visual acuity. (queensu.ca)
  • 19. C Both achromatopsia and prospognosia are caused by lesions on the fusiform gyrus of the occipitotemporal cortex. (brainaacn.org)
  • Furthermore, we found that the strength of reciprocal intracortical connections between primary and secondary sensory areas are unequal, with connections from primary to secondary sensory areas being stronger than the reciprocal. (nih.gov)
  • A rapid, transient, all-or-none electrical impulse generated by a neuron at the axon hillock propagated toward the synapse. (neuropetvet.com)
  • That neuron sends a signal along its axon to excite the biceps brachii, causing contraction of the muscle and flexion of the forearm at the elbow to withdraw the hand from the hot stove. (lumenlearning.com)
  • Fourth, to restore some visual function in blind animals by targeting optogenetic sensors to LGN cells and stimulating their axon terminals with light patterns. (europa.eu)
  • 2014). Recent studies have indicated that specific retinal ganglion cells (RGCs) and neurons in their non-image-forming target nuclei can express the same guidance molecules, the deletion of which causes defects in retinal axon targeting (Osterhout et al. (deepdyve.com)
  • Like the Ten-m family, Ten-m3 plays a critical role in regulating connectivity of the nervous system, particularly in axon pathfinding and synaptic organisation in the motor and visual system. (wikipedia.org)
  • Expanding the explanation of the withdrawal reflex can include inhibition of the opposing muscle, or cross extension, either of which increase the complexity of the example by involving more central neurons. (lumenlearning.com)
  • 1997 ). This compression of visual space is due in part to an extraretinal signal related to the eye movement command, since little or no such effect is observed in the absence of an eye movement (Morrone, Ross, & Burr, 1997 ). (arvojournals.org)
  • To better understand the relationship between movement and vision, a team of researchers looked at what happens in one of the brain's primary regions for analyzing imagery when animals are free to roam naturally. (genengnews.com)
  • In fact, the researchers describe two sets of movement-related patterns in the visual cortex that are based on head motion and whether an animal is in the light or the dark. (genengnews.com)
  • It was really surprising to see this type of [movement-related] information in the visual cortex because traditionally people have thought of the visual cortex as something that only processes images," said Grigori Guitchounts, PhD, a postdoctoral researcher in the neurobiology department at Harvard Medical School and the study's lead author. (genengnews.com)
  • Many experiments since then have followed their model, but it did not illuminate how movement affects the neurons that analyze. (genengnews.com)
  • Furthermore, repetitive high frequency burst spiking of a single rat cortical neuron could trigger a switch between the cortical states resembling slow-wave and rapid-eye-movement sleep [ 15 ]. (hindawi.com)
  • It is well known that neurons in primary motor cortex change their tuning to movement when arm workspace changes. (cmu.edu)