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Visual Cortex
The visual cortex of the brain is the area of the cerebral cortex that processes visual information. It is located in the occipital lobe. Sensory input originating from the eyes travels through the lateral geniculate nucleus in the thalamus and then reaches the visual cortex. The area of the visual cortex that receives the sensory input from the lateral geniculate nucleus is the primary visual cortex, also known as visual area 1 ( V1), Brodmann area 17, or the striate cortex. The extrastriate areas consist of visual areas 2, 3, 4, and 5 (also known as V2, V3, V4, and V5, or Brodmann area 18 and all Brodmann area 19). Both hemispheres of the brain include a visual cortex; the visual cortex in the left hemisphere receives signals from the right visual field, and the visual cortex in the right hemisphere receives signals from the left visual field. Introduction The primary visual cortex (V1) is located in and around the calcarine fissure in the occipital lobe. Each hemisphere's V1 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Brain
A brain is an organ that serves as the center of the nervous system in all vertebrate and most invertebrate animals. It is located in the head, usually close to the sensory organs for senses such as vision. It is the most complex organ in a vertebrate's body. In a human, the cerebral cortex contains approximately 14–16 billion neurons, and the estimated number of neurons in the cerebellum is 55–70 billion. Each neuron is connected by synapses to several thousand other neurons. These neurons typically communicate with one another by means of long fibers called axons, which carry trains of signal pulses called action potentials to distant parts of the brain or body targeting specific recipient cells. Physiologically, brains exert centralized control over a body's other organs. They act on the rest of the body both by generating patterns of muscle activity and by driving the secretion of chemicals called hormones. This centralized control allows rapid and coordinated respon ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Calcarine Artery
The posterior cerebral artery (PCA) is one of a pair of cerebral arteries that supply oxygenated blood to the occipital lobe, part of the back of the human brain. The two arteries originate from the distal end of the basilar artery, where it bifurcates into the left and right posterior cerebral arteries. These anastomose with the middle cerebral artery, middle cerebral arteries and internal carotid artery, internal carotid arteries via the posterior communicating arteries. Structure The posterior cerebral artery is subdivided into 4 sections P1: pre-communicating segment * Originated at the termination of the basilar artery * May give rise to the artery of Percheron if present P2: post-communicating segment * From the PCOM around the midbrain * Terminates as it enters the quadrigeminal ganglion * Gives rise to the choroidal branches (medial and lateral posterior choroidal arteries) P3: quadrigeminal segment * Courses posteromedially through the quadrigeminal cistern * ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ebbinghaus Illusion
The Ebbinghaus illusion or Titchener circles is an optical illusion of relative size perception. Named for its discoverer, the German psychologist Hermann Ebbinghaus (1850–1909), the illusion was popularized in the English-speaking world by Edward B. Titchener in a 1901 textbook of experimental psychology, hence its alternative name. In the best-known version of the illusion, two circles of identical size are placed near to each other, and one is surrounded by large circles while the other is surrounded by small circles. As a result of the juxtaposition of circles, the central circle surrounded by large circles appears smaller than the central circle surrounded by small circles. Recent work suggests that two other critical factors involved in the perception of the Ebbinghaus illusion are the distance of the surrounding circles from the central circle and the completeness of the annulus, which makes the illusion comparable in nature to the Delboeuf illusion. Regardless of relati ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Melvyn A
Melvyn is a masculine given name which may refer to: * Melvyn Betts (born 1975), English cricketer * Melvyn Bragg (born 1939), British broadcaster and author * Melvyn Caplan, British Conservative politician * Melvyn Douglas (1901-1981), American actor * Melvyn Dubofsky (born 1934), American professor of history and sociology * Melvyn Gale (born 1952), English cellist, former member of the Electric Light Orchestra * Melvyn Goldstein (born 1938), American social anthropologist * Melvyn Grant (born 1944), English artist and illustrator * Melvyn Greaves (born 1941), British cancer biologist and professor * Mel Gussow (1933-2005), American theater critic, movie critic, and author * Melvyn Hayes (born 1935), English actor * Melvyn Jaminet, (born 1999), French rugby footballer * Melvyn Jones (born 1964), British retired slalom canoer * Melvyn P. Leffler (born 1945), American historian and professor * Melvyn Levitsky (born 1938), American diplomat and former ambassador * Melvyn Lorenzen (bo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mortimer Mishkin
Mortimer Mishkin (December 13, 1926 – October 2, 2021) was an American neuropsychologist, and winner of the 2009 National Medal of Science awarded in Behavior and Social Science. Life and career Born in Fitchburg, Massachusetts in December 1926, Mishkin graduated from Dartmouth College in 1946, and took a 1949 M.A. and 1951 Ph.D. from McGill University under Donald O. Hebb. His Ph.D. thesis was partly directed by surgeon and theorist Karl H. Pribram. In 2010 Mishkin won the National Medal of Science for his five decades of work on the mechanisms of cognition and memory, and the discovery that the brain processes memories in two separate processes: cognitive memory dealing with events and fresh information, and behavioral memory related to skills and habits. As of 2016 Mishkin was Chief of the Section on Cognitive Neuroscience, Laboratory of Neuropsychology, National Institute of Mental Health, chartered to explore neurobiological mechanisms of perception and memory. He is als ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Leslie Ungerleider
Leslie G. Ungerleider (1946–2020) was an Experimental psychology, experimental psychologist and neuroscientist, previously Chief of the Laboratory of Brain and Cognition at the National Institute of Mental Health. Ungerleider was known for introducing the concepts of the dorsal stream, dorsal (where) and ventral stream, ventral (what) streams, two pathways of information processing in the brain that specialize in visuospatial processing and object recognition, respectively. Ungerleider received a B.A. from Binghamton University and a Ph.D. in experimental psychology from New York University, and she completed a postdoctoral researcher, postdoctoral fellowship with Karl H. Pribram, Karl Pribram at Stanford University, where she began her work on higher-order perceptual mechanisms in the Cerebral cortex, cortex of primates. In 1975 she moved to the National Institute of Mental Health, where she remained for the remainder of her career, initially joining Mortimer Mishkin in the La ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Saccade
A saccade ( , French for ''jerk'') is a quick, simultaneous movement of both eyes between two or more phases of fixation in the same direction.Cassin, B. and Solomon, S. ''Dictionary of Eye Terminology''. Gainesville, Florida: Triad Publishing Company, 1990. In contrast, in smooth pursuit movements, the eyes move smoothly instead of in jumps. The phenomenon can be associated with a shift in frequency of an emitted signal or a movement of a body part or device. Controlled cortically by the frontal eye fields (FEF), or subcortically by the superior colliculus, saccades serve as a mechanism for fixation, rapid eye movement, and the fast phase of optokinetic nystagmus. The word appears to have been coined in the 1880s by French ophthalmologist Émile Javal, who used a mirror on one side of a page to observe eye movement in silent reading, and found that it involves a succession of discontinuous individual movements. Function Humans and many animals do not look at a scene in f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Posterior Parietal Cortex
The posterior parietal cortex (the portion of parietal neocortex posterior to the primary somatosensory cortex) plays an important role in planned movements, spatial reasoning, and attention. Damage to the posterior parietal cortex can produce a variety of sensorimotor deficits, including deficits in the perception and memory of spatial relationships, inaccurate reaching and grasping, in the control of eye movement, and inattention. The two most striking consequences of PPC damage are apraxia and hemispatial neglect. Anatomy The posterior parietal cortex receives input from the three sensory systems that play roles in the localization of the body and external objects in space: the visual system, the auditory system, and the somatosensory system. In turn, much of the output of the posterior parietal cortex goes to areas of frontal motor cortex: the dorsolateral prefrontal cortex, various areas of the secondary motor cortex, and the frontal eye field. The posterior parietal cortex ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dorsomedial Area
The visual cortex of the brain is the area of the cerebral cortex that processes visual perception, visual information. It is located in the occipital lobe. Sensory input originating from the eyes travels through the lateral geniculate nucleus in the thalamus and then reaches the visual cortex. The area of the visual cortex that receives the sensory input from the lateral geniculate nucleus is the primary visual cortex, also known as visual area 1 (Brodmann area#BA17,V1, V1), Brodmann area 17, or the striate cortex. The extrastriate cortex, extrastriate areas consist of visual areas 2, 3, 4, and 5 (also known as V2, V3, V4, and V5, or Brodmann area 18 and all Brodmann area 19). Both cerebral hemisphere, hemispheres of the brain include a visual cortex; the visual cortex in the left hemisphere receives signals from the right visual field, and the visual cortex in the right hemisphere receives signals from the left visual field. Introduction The primary visual cortex (V1) is located ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Long-term Memory
Long-term memory (LTM) is the stage of the Atkinson–Shiffrin memory model in which informative knowledge is held indefinitely. It is defined in contrast to short-term and working memory, which persist for only about 18 to 30 seconds. Long-term memory is commonly labelled as explicit memory ( declarative), as well as episodic memory, semantic memory, autobiographical memory, and implicit memory (procedural memory). Dual-store memory model According to Miller, whose paper in 1956 popularized the theory of the "magic number seven", short-term memory is limited to a certain number of chunks of information, while long-term memory has a limitless store. Atkinson–Shiffrin memory model According to the dual store memory model proposed by Richard C. Atkinson and Richard Shiffrin in 1968, memories can reside in the short-term "buffer" for a limited time while they are simultaneously strengthening their associations in long-term memory. When items are first presented, they enter sh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Inferior Temporal Cortex
The inferior temporal gyrus is one of three gyri of the temporal lobe and is located below the middle temporal gyrus, connected behind with the inferior occipital gyrus; it also extends around the infero-lateral border on to the inferior surface of the temporal lobe, where it is limited by the inferior Sulcus (neuroanatomy), sulcus. This region is one of the higher levels of the ventral stream of visual processing, associated with the representation of objects, places, faces, and colors. It may also be involved in face perception, and in the recognition of numbers and words. The inferior temporal gyrus is the anterior region of the temporal lobe located underneath the central temporal sulcus. The primary function of the occipital temporal gyrus – otherwise referenced as IT cortex – is associated with visual stimuli processing, namely visual object recognition, and has been suggested by recent experimental results as the final location of the ventral cortical visual system. The ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Two-streams Hypothesis
The two-streams hypothesis is a model of the neural processing of vision as well as hearing. The hypothesis, given its initial characterisation in a paper by David Milner and Melvyn A. Goodale in 1992, argues that humans possess two distinct visual systems. Recently there seems to be evidence of two distinct auditory systems as well. As visual information exits the occipital lobe, and as sound leaves the phonological network, it follows two main pathways, or "streams". The ventral stream (also known as the "what pathway") leads to the temporal lobe, which is involved with object and visual identification and recognition. The dorsal stream (or, "where pathway") leads to the parietal lobe, which is involved with processing the object's spatial location relative to the viewer and with speech repetition. History Several researchers had proposed similar ideas previously. The authors themselves credit the inspiration of work on blindsight by Weiskrantz, and previous neuroscientific ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
