BOTH ELECTROLYTIC AND EXCITOTOXIC LESIONS OF NUCLEUS-ACCUMBENS DISRUPT LATENT INHIBITION OF LEARNING IN RATS

Evidence indicating a role for the nucleus accumbens in the developmen t of latent inhibition of learning has accumulated. Two experiments we re conducted using Wistar rats to investigate this role directly. Expe riment 1 used a conditioned emotional response paradigm to assess the effects of discrete electrolytic lesions in the shell region of the nu cleus accumbens. Latent inhibition was attenuated by this lesion. In o rder to determine the contribution made by damage to fibers en. passag e associated with electrolytic lesions, Experiment 2 assessed the effe cts of NMDA-induced lesions in the shell of the nucleus accumbens in t he same task. Latent inhibition was again significantly attenuated. Th ese findings support the proposition that an intact nucleus accumbens is necessary for the normal development of latent inhibition. (C) 1995 Academic Press, Inc.