Motor Cortex: From 1 Different Sources
the region of the *cerebral cortex that is responsible for initiating nerve impulses that bring about voluntary activity in the muscles of the body. It is possible to map out the cortex to show which of its areas is responsible for which particular part of the body. The motor cortex of the left cerebral hemisphere is responsible for muscular activity in the right side of the body.
The tissues that form the outer part of an organ and which are positioned just below the capsule or outer membrane. Examples are the cerebal cortex of the BRAIN and the renal cortex of the KIDNEYS.... cortex
See BRAIN.... sensory cortex
A term usually applied to nerves, used to describe anything that results in movement. Motor nerves stimulate muscles to contract, producing movement. (See also SENSORY.)... motor
A group of disorders of unknown origin. Certain cells in the neurological system’s MOTOR nerves degenerate and die. Upper and lower motor neurones may be affected but sensory cells retain their normal functions. Three types of MND are identi?ed: amyotrophic lateral sclerosis (AML – 50 per cent of patients); progressive muscular atrophy (25 per cent), in which the prognosis is better than for AML; and bulbar palsy (25 per cent). Men are affected more than women, and the disorder affects about seven people in every 100,000. Those affected develop progressive weakness and wasting of their muscles. The diagnosis is con?rmed with various tests including the measurement of electrical activity in muscles, electromyography, muscle BIOPSY, blood tests and X-ray examination of the spine. There is no medical treatment: patients need physical and psychological support with aids to help them overcome disabilities. The Motor Neurone Disease Association provides excellent advice and help for sufferers and their relatives. (See APPENDIX 2: ADDRESSES: SOURCES OF INFORMATION, ADVICE, SUPPORT AND SELF-HELP.)... motor neurone disease (mnd)
The outer covering of the two adrenal glands that lie atop each kidney. Embryonically derived from gonad tissue, they make steroid hormones that control electrolytes, the management of fuels, the rate of anabolism, the general response to stress, and maintenance of nonspecific resistance.... adrenal cortex
the intricately folded outer layer of the *cerebrum, making up some 40% of the brain by weight and composed of an estimated 15 thousand million neurons (see grey matter). This is the part of the brain most directly responsible for consciousness, with essential roles in perception, memory, thought, mental ability, and intellect, and it is responsible for initiating voluntary activity. It has connections, direct or indirect, with all parts of the body. The folding of the cortex provides a large surface area, the greater part lying in the clefts (sulci), which divide the upraised convolutions (gyri). On the basis of its microscopic appearance in section, the cortex is mapped into *Brodmann areas; it is also divided into functional regions; including *motor cortex, *sensory cortex, and *association areas. Within, and continuous with it, lies the *white matter, through which connection is made with the rest of the nervous system.... cerebral cortex
one of the nerves that carry impulses outwards from the central nervous system to bring about activity in a muscle or gland. Compare sensory nerve.... motor nerve
one of the units (*neurons) that goes to make up the nerve pathway between the brain and an effector organ, such as a skeletal muscle. An upper motor neuron has a cell body in the brain and an axon that extends into the spinal cord, where it ends in synapses. It is thus entirely within the central nervous system. A lower motor neuron, on the other hand, has a cell body in the spinal cord or brainstem and an axon that extends outwards in a cranial or spinal motor nerve to reach an effector.... motor neuron
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