Abstract
The evoked potential in the lateral hypothalamus (LH) recorded by stimulation of basal medial amygdaloid nucleus (Abm) showed a triphasic pattern and diazepam (2 mg/kg, i. p.) decreased the late component. The evoked potential in the midbrain reticular formation (MRF) recorded by stimulation of Abm showed a fast component with a relatively short latency followed by a biphasic late component and diazepam decreased the late component. Though the evoked potential in the Abm recorded by stimulation of LH showed a triphasic pattern, diazepam had no influence on the amplitude. Diazepam increased markedly the amplitude of evoked potential in the MRF recorded by stimulation of LH. Diazepam was ineffective on the evoked potential in the Abm recorded by stimulation of MRF. Diazepam decreased markedly the late component of evoked potential in the LH recorded by stimulation of MRF. These results suggest that the depression of emotional behavior by diazepam may be particularly related to the fact that the evoked potential in the LH recorded by stimulation of Abm was decreased by diazepam.