[The participation of brain mediator and peptidergic systems in the mechanisms of the conditioned reflex].

In dogs with implanted chemotrodes and microelectrodes, the role of acetylcholine-, dopamine-, GABA- and P-ergic systems of the caudate nucleus and amygdala in positive and inhibitory conditioning, was studied. Activation of the same transmitter system in different structures could exert different behavioral effects, whereas activation of different transmitter subcortical systems could induce the same behavioral responses. The effects of activating or blocking agents upon the mediator subcortical system depended on the functional state of the nervous-system at the moment of administration as well as on the site of administration. It seems difficult to predict a contribution of one or another subcortical structure in organization of behavioral acts.