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cybernetics

(Encyclopedia)cybernetics [Gr.,=steersman], term coined by American mathematician Norbert Wiener to refer to the general analysis of control systems and communication systems in living organisms and machines. In cy...

chorea

(Encyclopedia)chorea kərēˈə, kō– [key] or St. Vitus's dance, acute disturbance of the central nervous system characterized by involuntary muscular movements of the face and extremities. The disease, known al...

tranquilizer

(Encyclopedia)tranquilizer, drug whose action calms the central nervous system, decreasing emotional agitation without impairing alertness. Tranquilizing drugs differ from hypnotic drugs such as barbiturates in tha...

heartburn

(Encyclopedia)heartburn, burning sensation beneath the breastbone, also called pyrosis. Heartburn does not indicate heart malfunction but results from nervous tension or overindulgence in food or drink. The sensati...

coccidioidomycosis

(Encyclopedia)coccidioidomycosis kŏksĭdˌēoiˌdōmīkōˈsĭs [key], systemic fungus disease (see fungal infection) endemic to arid regions of the Americas, contracted by inhaling dust containing spores of the f...

physiology

(Encyclopedia)physiology fĭzēŏlˈəjē [key], study of the normal functioning of animals and plants during life and of the activities by which life is maintained and transmitted. It is based fundamentally on the...

trichinosis

(Encyclopedia)trichinosis trĭkˌĭnīˈəsĭs [key], parasitic disease caused by the roundworm Trichinella spiralis. It follows the eating of raw or inadequately cooked meat, especially pork. The larvae are releas...

synapse

(Encyclopedia)synapse sĭnˈăps [key], junction between various signal-transmitter cells, either between two neurons or between a neuron and a muscle or gland. A nerve impulse reaches the synapse through the axon,...

meninges

(Encyclopedia)CE5 Meninges: Section of spine showing meningeal layers meninges mĭnĭnˈjēz [key], three membranous layers of connective tissue that envelop the brain and spinal cord (see nervous system). The ...

depressant

(Encyclopedia)depressant, any one of various substances that diminish functional activity, usually by depressing the nervous system. Barbiturates, sedatives, alcohol, and meprobamate are all depressants. Depressant...