Active electrogenesis of command neurons of defense behavior of the snail during conditioning.

A change in the active electrogenesis of command neurons of the defensive closing of the spiracle of the edible snail during the development, extinction, and repeat development of a classical conditioned defense reflex in response to tactile stimulation is described in this study; the tactile stimulation of another point of the body served as the differential stimulus. As the biological significance of the conditional stimulus increased as the result of training, the excitability of the command neurons in response to this stimulus increased. At the same time, the neurons manifested reduced excitability in response to the differential stimulus. The possible mechanisms of the rapid reorganization of the excitability of the neurons and the functional significance of the change in the generation threshold of the AP are discussed.