excitation


excitation
1. The act of increasing the rapidity or intensity of the physical or mental processes. 2. In neurophysiology, the complete all-or-none response of a nerve or muscle to an adequate stimulus, ordinarily including propagation of e. along the membranes of the cell or cells involved. SEE ALSO: stimulation.
- anomalous atrioventricular e. ectopic atrial beat conducted to the ventricle.

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ex·ci·ta·tion .ek-.sī-'tā-shən, .ek-sə- n EXCITEMENT: as
a) the disturbed or altered condition resulting from arousal of activity (as by neural or electrical stimulation) in an individual organ or tissue
b) the arousing of such activity

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n.
(in neurophysiology) the triggering of a conducted impulse in the membrane of a muscle cell or nerve fibre. During excitation a polarized membrane becomes momentarily depolarized and an action potential is set up.

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ex·ci·ta·tion (ek″si-taґshən) [L. excitatio, from ex out + citare to call] an act of irritation or stimulation or of responding to a stimulus; the addition of energy, as the excitation of a molecule by absorption of photons.

Medical dictionary. 2011.