Differential control over cocaine-seeking behavior by nucleus accumbens core and shell.
Nucleus accumbens (NAc) dopamine is widely implicated in mediating the reinforcing effects of drugs of abuse. However, the precise function of the NAc itself in drug self-administration has been difficult to establish. Here we show a neural double-dissociation of the behavioral processes that underlie cocaine self-administration in rats. Whereas selective excitotoxic lesions of the NAc core had only a minor effect on the acquisition of responding for cocaine under a standard schedule of continuous reinforcement, these lesions profoundly impaired the acquisition of drug-seeking behavior that was maintained by drug-associated conditioned reinforcers and assessed using a second-order schedule of cocaine reinforcement. In contrast, selective excitotoxic lesions of the NAc shell did not impair drug self-administration or the acquisition of cocaine-seeking, but they did attenuate the psychostimulant effects of cocaine. These results further our understanding of how the NAc controls drug-seeking and drug-taking behavior.
Ito
Rutsuko
R
Department of Experimental Psychology, University of Cambridge, Downing Street, Cambridge CB1 1BB, UK.
Robbins
Trevor W
TW
Everitt
Barry J
BJ
D000818:Animals; D001070:Appetitive Behavior / Q000187:drug effects / Q000502:physiology*; D001245:Association Learning / Q000502:physiology; D003042:Cocaine / Q000008:administration & dosage*; D019970:Cocaine-Related Disorders / Q000503:physiopathology*; D004195:Disease Models, Animal; D004305:Dose-Response Relationship, Drug; D008297:Male; D009714:Nucleus Accumbens / Q000187:drug effects / Q000502:physiology*; D051381:Rats; D011919:Rats, Inbred Strains; D012054:Reinforcement, Psychology; D012646:Self Administration
D003042:Cocaine