motor area

area /ar·ea/ (ār´e-ah) pl. a´reae, areas   [L.] a limited space; in anatomy, a specific surface or functional region.

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association areas  areas of the cerebral cortex (excluding primary areas) connected with each other and with the neothalamus; they are responsible for higher mental and emotional processes, including memory, learning, etc.

auditory areas  two contiguous areas of the temporal lobe in the region of the anterior transverse temporal gyrus.

Broca's motor speech area  an area comprising parts of the opercular and triangular portions of the inferior frontal gyrus; injury to this area may result in motor aphasia.

Brodmann's areas  areas of the cerebral cortex distinguished by differences in arrangement of their six cellular layers; identified by numbering each area.

embryonic area  see under disc.

germinal area  embryonic disc.

hypophysiotropic area  the hypothalamic component containing neurons that secrete hormones that regulate adenohypophysial cells.

Kiesselbach's area  one on the anterior part of the nasal septum above the intermaxillary bone, richly supplied with capillaries, and a common site of nosebleed.

motor area  any area of the cerebral cortex primarily involved in stimulating muscle contractions, often specifically the primary somatomotor area.

prefrontal area  the cortex of the frontal lobe immediately in front of the premotor cortex, concerned chiefly with associative functions.

premotor area  the motor cortex of the frontal lobe immediately in front of the precentral gyrus.

primary areas  areas of the cerebral cortex comprising the motor and sensory regions; cf. association a's.

primary somatomotor area  an area in the posterior part of the frontal lobe just anterior to the central sulcus; different regions control motor activity of specific parts of the body.

area subcallo´sa , subcallosal area a small area of cortex on the medial surface of each cerebral hemisphere.

area of superficial cardiac dullness  a triangular area of dullness observed on percussion of the chest, corresponding to the area of the heart not covered by lung tissue.

thymus-dependent area  any of the areas of the peripheral lymphoid organs populated by T lymphocytes, e.g., the paracortex in lymph nodes, the centers of the malpighian corpuscle of the spleen, and the internodal zone of Peyer's patches.

thymus-independent area  any of the areas of the peripheral lymphoid organs populated by B lymphocytes, e.g., the spleen lymph nodules and the lymph nodes.

vocal area  rima glottidis.

watershed area  any of several areas over the convexities of the cerebral or cerebellar hemispheres; at times of prolonged systemic hypotension they are particularly susceptible to infarction.

Wernicke's area , Wernicke's second motor speech area originally a term denoting a speech center on the posterior part of the superior temporal gyrus, now used to include also the supramarginal and angular gyri.

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motor area

n.

See motor cortex.

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motor area,

a portion of the cerebral cortex that includes the precentral gyrus and the posterior part of the frontal gyri and that causes the contraction of the voluntary muscles on stimulation with electrodes. Normal voluntary activity requires associations between the motor area and other parts of the cortex; removal of the motor area from one cerebral hemisphere causes paralysis of voluntary muscles, especially of the opposite side of the body. Various parts of the motor area are associated with different body structures, such as the lower limb, the face, the mouth, and the hand. The parts associated with more delicate, complicated movements, such as those of the hand, are larger than those associated with more general movements.

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area

pl. areae, areas [L.] a limited space or plane surface.

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association a's

areas of the cerebral cortex (excluding primary areas) connected with each other and with the neothalamus; they are responsible for higher mental and emotional processes, including memory, learning, etc.

Brodmann's a's

specific occipital and preoccipital areas of the cerebral cortex, distinguished by differences in the arrangement of their six cellular layers, and identified by numbering each area.

cardiogenic area

in the embryo includes heart and pericardial rudiments.

central retinal area

the area of the retina, dorsal to the optic papilla, along the optical axis. Here the retinal vessels are missing.

In cattle the area is poorly defined as two areas; a rounded area concerned with binocular vision and a horizontal strip concerned wuth monocular vision.

area cerebrovasculosa

in anencephaly the cerebral hemispheres are replaced by a sheet of tissue composed largely of blood vessels called the area cerebrovasculosa.

area cribrosa

that part of the renal crest or renal papilla at which the papillary ducts open into the pelvis.

germinal area, area germinativa

embryonic disk.

area medullovasculosa

the central part of a spinal meningomyelocele. It is a raised, reddish protuberance devoid of skin and consists of spinal cord with a surrounding vascular network.

motor area

that area of the cerebral cortex which, on brief electrical stimulation, shows the lowest threshold and shortest latency for the production of muscle movement.

area nuda

an area on the surface of a viscus that has no serosal covering.

olfactory area

1. the part of the piriform lobe of the brain associated with olfaction.

2. a more general area including the olfactory bulb, tract and trigone.

area opaca

the opaque area of the embryonic disk of the fertilized avian egg surrounding the area pellucida; it forms some extraembryonic structures.

area pellucida

the clear central part of the developing embryonic disk in a fertilized avian egg. Produces the embryo's tissues.

area piriformis temporalis

the cortical area of the piriform lobe of the brain.

primary area

areas of the cerebral cortex comprising the motor and sensory regions.

psychomotor area

motor area.

area sampling

see area sampling.

silent area

an area of the brain in which pathological conditions may occur without producing clinical signs.

vocal area

the part of the glottis between the vocal cords.