DISTURBANCES OF NEOPHOBIA AND TASTE-AVERSION LEARNING AFTER BILATERALKAINATE MICROLESIONS IN THE RAT PALLIDUM

These experiments aimed to elucidate feeding-associated behavioral rol es of globus pallidus (GP) neurons in gustatory functions: The effects of bilateral microiontophoretic kainate (KA) lesions of the ventromed ial pallidal (vmGP) region on neophobia and conditioned taste aversion (CTA) were studied. Lesioned rats displayed strong and persistent neo phobia to a mild citric acid solution. Neuron-specific damage to the v mGP also prevented rats from proper acquisition of CTA. Rats that prev iously showed normal neophobia and successfully learned CTA demonstrat ed difficulties in CTA retention after GP lesions. KA-lesioned rats, i n addition, exhibited deficits in orientation reactions but did not ha ve aphagia, adipsia, or motor disturbances seen after larger pallidal lesions. These findings suggest that neurons of the GP are significant in acquisition, memory storage, and retrieval mechanisms of feeding-a ssociated taste information.