Changes in hippocampal rhythmic slow activity during instrumental cardiovascular conditioning in the monkey (Macaca...

Analyses of 4-8 Hz electrical activity (RSA) of the mid-ventral hippocampus, motor activity (M), and blood pressure were carried out during experiments in which three monkeys were operantly conditioned to slow heart rate (HR), to speed HR or during control, no feedback (FB) periods. The results showed that RSA activity was greater during contingent HR (FB) slowing than during HR slowing noncontingent (FB) for all three animals. Motor activity tended to show small changes across conditions; however, it was higher during HR speeding and lower during HR slowing in two animals. There was no differential effect of FB on motor activity for any animal. Blood pressure changes were small and variable throughout conditioning, RSA changes tended to be highly consistent both early and late in conditioning. Results are discussed in terms of attentional and somatic factors that may be operative during instrumental cardiovascular conditioning.