Loss of cholinergic neurons in the rat neocortex produces deficits in passive avoidance learning.

Bilateral kainic acid lesions of the ventral globus pallidus produced a significant and selective cortical decrease in choline acetyltransferase activity in the rat brain. When lesioned and control subjects were compared on performance of a step-through passive avoidance task, lesioned rats showed a marked retention deficit 24 hr after the initial training trial. This experimentally-induced memory deficit associated with a cortical cholinergic neuronal loss resembles the deficits in senile dementia of the Alzheimer type and may provide a useful animal model for studying the disease.