Hippocampal slow wave activity during appetitive and aversive conditioning in the cat

The electrical activity of the dorsal and ventral divisions of the hippocampus was investigated quantitatively during the development of discriminative operant training and defensive conditioning. Signal-related (respondent, sign-tracking) and goal-directed (operant, 'voluntary') activities and their hippocampal electrical correlates were compared. Signal-related behaviour was accompanied by significantly higher frequency spectral peaks than lever press behaviour. Spectral peaks were higher during lever pressing in early stages of training as compared to criterion performance. In defensive conditioning overt sign-tracking behaviour disappeared but spectral peak shifts toward higher values upon signal presentation persisted. Comparison of dorsal and ventral hippocampal activity revealed high coherence values and similar frequency shifts during behaviour transitions. These findings argue against suggestions that a close relationship exists between elementary motor acts and hippocampal EEG.