Focal hippocampal epilepsy: effect of caudate stimulation

The basal ganglia seem to be involved in the control of abnormal hippocampal activity. The caudate nucleus has been reported to elicit hippocampal theta rhythm and to inhibit epileptiform spikes. Experiments were conducted to test the action of caudate stimulation on focal penicillin epilepsy of the hippocampus in the cat prior to and after septal coagulation and parenteral atropine administration. Results showed that the caudate is able to reduce both hippocampal spike frequency and amplitude. The effects are abolished by septal lesions and either decreased or totally suppressed by atropine administration. The findings are discussed in terms of caudate influence on septum; the importance of cholinergic pathways is also emphasized.