[Neurons of the rabbit midbrain reticular formation during a defensive conditioned reflex].

Analysis of unit activity of the midbrain reticular formation was carried out on alert rabbits during defensive conditioning. Most of the examined neurones exhibited phasic responses corresponding in time to the components of the evoked potential (EP) recorded in the cortical visual area in response to the "indifferent" stimulus, and to the conditioned stimulus and electric cutaneous reinforcement. The data obtained are considered from the standpoint of the Anokhin functional systems theory. A conclusion has been made regarding the participation of reticular units in providing all the basic mechanisms of the functional system of the behavioral act. Discharges of one and the same neurone may correspond to different components of the EPs to conditioned and unconditioned stimuli. In different behavioral acts a neurone may apparently participate in different systemic mechanisms.