SFN 2000 autoshaping – 1 of 9 Effects of limbic corticostriatal lesions on autoshaping performance in rats BJ Everitt, JA Parkinson † , G Lachenal, KM Halkerston, N Rudarakanchana, RN Cardinal, J Hall, CH Morrison, JW Dalley, SR Howes, TW Robbins Departments of Experimental Psychology and † Anatomy, University of Cambridge, UK Abstract. It has previously been shown that acquisition of Pavlovian conditioned approach behaviour (autoshaping) in rats depends on a cir- cuit involving the anterior cingulate cortex (Ant Cing), the nucleus accumbens core (AcbC), accumbens dopamine (DA) innervation, and the central nucleus of the amygdala (CeN). This study sought to determine which elements of this circuit are required for performance of the task in well-trained animals. Rats were first trained that one visual stimulus, the CS+, was always followed by food, while another, the CS–, never predicted food. As a consequence, they came to approach the CS+ selectively. Subjects that reached a performance criterion subsequently re- ceived excitotoxic lesions of the Ant Cing (lesion n = 11 / sham 6), AcbC (ns = 9 / 7), or CeN (8 / 7), or 6-OHDA-induced dopamine de- pletion of the entire nucleus accumbens (7 / 7). Subjects were then re-tested. Ant Cing lesions and AcbC lesions both impaired autoshaping performance. Acb DA depletion also impaired performance and the impairment was correlated with the degree of dopamine depletion, though the deficit was mild compared to that observed for the acquisition of autoshap- ing (Everitt et al., 1999). In contrast, rats with CeN lesions were unimpaired. These results support the view that the limbic corticostriatal cir- cuit involving Ant Cing and AcbC is involved in the storage and/or expression of appetitive stimulus–reward associations, but suggest a criti- cal role for CeN in early learning, which may reflect its role as a controller of attentional resources (Holland & Gallagher, 1999).