[Nature of evoked responses of the dorsomedial nucleus of the thalamus to stimulation of the periamygdaloid cortex and anterior amygdaloid region of the rat brain].

Focal evoked potentials (FEP) and unit activity characteristics of the thalamic dorsomedial nucleus were compared with the periamygdaloid cortex (PC) and area amygdaloidea anterior (AAA) stimulation in acute experiment with rats. Some pattern differences of the FEP as well as differences of the recovery period of both activities to the PC and AAA stimulations are established. AAA and PC stimulation was followed by electrical activity changes in 19.2% and 26.9% of the units in question, respectively. Four types of neurons are found: active ones (64.3% of all responding units); two-phase active units (14.3%); inhibitory or inhibitory-active units (14.3%) and complex units (7.1%). PC stimulation evokes both short (12-18 ms) and long latency (23-66 ms) phasic-active unit responses, while AAA stimulation led to appearance of responses with latencies not less than 20 ms (21-136 ms). Responses of the first two types were peculiar to 92.9% and 64.3% of units responding to PC and AAA stimulation, respectively.