Abstract
Brain stem lesions and stimulation effects upon prefrontal electrical activity in relation to limbic evoked potentials and after-discharges were studied in 20 squirrel monkeys. The studies were performed under phencyclidine hydrochloride (Sernylan) anesthesia.
After-discharges elicited from the amygdala and hippocampus propagated to the prefrontal cortex following the lesion in the field H of Forel, whereas the septal stimulation elicited a self-sustained prefrontal after-discharge and a limbic after-discharge. Evoked potentials in the prefrontal cortex with the stimulation of the septum, amygdala, and hippocampus were attenuated by the conditioning stimuli in the field H of Forel.
It was concluded that the lesion in the field H of Forel increased the excitability of prefrontal cortex to limbic stimulation and after-discharges.
