Electrophysiological investigation of hypothalamo-neocortical connections in Macaca mulatta

Functional relations between phylogenetically different parts of the hypothalamus and the neocortex were studied by the method of recording evoked potentials (EP) and evoked single unit responses in acute experiments on monkeys (Macaca mulatta). The focus of maximal activity of EP and of single unit responses was found to be in the frontal association cortex, where evoked responses with the shortest latencies were recorded. During stimulation of the posterior hypothalamus, mainly unit responses of excitatory character were recorded in the neocortex, whereas during stimulation of the lateral hypothalamus mainly unit responses of inhibitory character were recorded.