- 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.
* * *a) the disturbed or altered condition resulting from arousal of activity (as by neural or electrical stimulation) in an individual organ or tissueb) the arousing of such activity
* * *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.
* * *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.