The central nervous system (CNS) is the part of the nervous system consisting primarily of the brain and spinal cord. The CNS is so named because the brain integrates the received information and coordinates and influences the activity of all parts of the bodies of bilaterally symmetric animals—that is, all multicellular animals except sponges and jellyfish. It is a structure composed of nervous tissue positioned along the rostral to caudal axis of the body and may have an enlarged section at the rostral end which is a brain. Not all animals with a central nervous system have a brain, although the large majority do.
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.
The cerebral cortex, also known as the cerebral mantle, is the outer layer of neural tissue of the cerebrum of the brain in humans and other mammals. The cerebral cortex mostly consists of the six-layered neocortex, with just 10% consisting of allocortex. It is separated into two cortices, by the longitudinal fissure that divides the cerebrum into the left and right cerebral hemispheres. The two hemispheres are joined beneath the cortex by the corpus callosum. The cerebral cortex is the largest site of neural integration in the central nervous system. It plays a key role in attention, perception, awareness, thought, memory, language, and consciousness.
Roger Wolcott Sperry was an American neuropsychologist, neurobiologist and Nobel laureate who, together with David Hunter Hubel and Torsten Nils Wiesel, won the 1981 Nobel Prize in Physiology and Medicine for his work with split-brain research. A Review of General Psychology survey, published in 2002, ranked Sperry as the 44th most cited psychologist of the 20th century.
Visual thinking, also called visual or spatial learning or picture thinking, is the phenomenon of thinking through visual processing. Visual thinking has been described as seeing words as a series of pictures. It is common in approximately 60–65% of the general population. "Real picture thinkers", those who use visual thinking almost to the exclusion of other kinds of thinking, make up a smaller percentage of the population. Research by child development theorist Linda Kreger Silverman suggests that less than 30% of the population strongly uses visual/spatial thinking, another 45% uses both visual/spatial thinking and thinking in the form of words, and 25% thinks exclusively in words. According to Kreger Silverman, of the 30% of the general population who use visual/spatial thinking, only a small percentage would use this style over and above all other forms of thinking, and can be said to be true "picture thinkers".
The vertebrate cerebrum (brain) is formed by two cerebral hemispheres that are separated by a groove, the longitudinal fissure. The brain can thus be described as being divided into left and right cerebral hemispheres. Each of these hemispheres has an outer layer of grey matter, the cerebral cortex, that is supported by an inner layer of white matter. In eutherian (placental) mammals, the hemispheres are linked by the corpus callosum, a very large bundle of nerve fibers. Smaller commissures, including the anterior commissure, the posterior commissure and the fornix, also join the hemispheres and these are also present in other vertebrates. These commissures transfer information between the two hemispheres to coordinate localized functions.
Split-brain or callosal syndrome is a type of disconnection syndrome when the corpus callosum connecting the two hemispheres of the brain is severed to some degree. It is an association of symptoms produced by disruption of, or interference with, the connection between the hemispheres of the brain. The surgical operation to produce this condition involves transection of the corpus callosum, and is usually a last resort to treat refractory epilepsy. Initially, partial callosotomies are performed; if this operation does not succeed, a complete callosotomy is performed to mitigate the risk of accidental physical injury by reducing the severity and violence of epileptic seizures. Before using callosotomies, epilepsy is instead treated through pharmaceutical means. After surgery, neuropsychological assessments are often performed.
The human brain is the central organ of the human nervous system, and with the spinal cord makes up the central nervous system. The brain consists of the cerebrum, the brainstem and the cerebellum. It controls most of the activities of the body, processing, integrating, and coordinating the information it receives from the sense organs, and making decisions as to the instructions sent to the rest of the body. The brain is contained in, and protected by, the skull bones of the head.
Torsten Nils Wiesel is a Swedish neurophysiologist. Together with David H. Hubel, he received the 1981 Nobel Prize in Physiology or Medicine, for their discoveries concerning information processing in the visual system; the prize was shared with Roger W. Sperry for his independent research on the cerebral hemispheres.
The Wada test, also known as the intracarotid sodium amobarbital procedure (ISAP) establishes cerebral language and memory representation of each hemisphere.
Betty Edwards is an American art teacher and author best known for her 1979 book Drawing on the Right Side of the Brain. She taught and did research at the California State University, Long Beach, until she retired in the late 1990s. While there, she founded the Center for the Educational Applications of Brain Hemisphere Research.
The longitudinal fissure is the deep groove that separates the two cerebral hemispheres of the vertebrate brain. Lying within it is a continuation of the dura mater called the falx cerebri. The inner surfaces of the two hemispheres are convoluted by gyri and sulci just as is the outer surface of the brain.
Corpus callosotomy is a palliative surgical procedure for the treatment of medically refractory epilepsy. In this procedure the corpus callosum is cut through in an effort to limit the spread of epileptic activity between the two halves of the brain.
Michael S. Gazzaniga is a professor of psychology at the University of California, Santa Barbara in the USA, where he heads the new SAGE Center for the Study of the Mind. He is one of the leading researchers in cognitive neuroscience, the study of the neural basis of mind. He is a member of the American Academy of Arts & Sciences, the Institute of Medicine, and the National Academy of Sciences.
The brain of Albert Einstein has been a subject of much research and speculation. Albert Einstein's brain was removed within seven and a half hours of his death. His apparent regularities or irregularities in the brain have been used to support various ideas about correlations in neuroanatomy with general or mathematical intelligence. Studies have suggested an increased number of glial cells in Einstein's brain.
The lateralization of brain function is the tendency for some neural functions or cognitive processes to be specialized to one side of the brain or the other. The medial longitudinal fissure separates the human brain into two distinct cerebral hemispheres, connected by the corpus callosum. Although the macrostructure of the two hemispheres appears to be almost identical, different composition of neuronal networks allows for specialized function that is different in each hemisphere.
The Herrmann Brain Dominance Instrument (HBDI) is a system to measure and describe thinking preferences in people, developed by William "Ned" Herrmann while leading management education at General Electric's Crotonville facility. It is a type of cognitive style measurement and model, and is often compared to psychological assessments such as the Myers-Briggs Type Indicator, Learning Orientation Questionnaire, DISC assessment, and others.
In human neuroanatomy, brain asymmetry can refer to at least two quite distinct findings:
In neuroscience, functional specialization is a theory which suggests that different areas in the brain are specialized for different functions.
Dual consciousness is a theoretical concept in neuroscience. It is proposed that it is possible that a person may develop two separate conscious entities within their one brain after undergoing a corpus callosotomy. The idea first began circulating in the neuroscience community after some split-brain patients exhibited the alien hand syndrome, which led some scientists to believe that there must be two separate consciousnesses within the brain's left and right hemispheres in competition with one another once the corpus callosum is severed.
