In support of a functional dichotomy between the dorsolateral/circumcommissural core (mediating cocaine reward and seeking at the cost of prosocial interaction) versus the medial shell (mediating prosocial interaction at the cost of drug seeking), lesions of the medial shell (with the lesions reaching well into the medial aspects of the accumbens corridor) but not the circumcommissural/dorsal core were shown to disrupt maternal behavior, that is, pup retrieval ( Li and Fleming, 2003 ).
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