Systems of reinforcement and drug dependence

Experimental data are presented in support of the hypothesis on the role of positive and negative reinforcing systems in the mechanism of drug dependence. Drugs with abuse potential (DAP) may change the manner of response to negative emotional stimuli, activate positive emotional reactions in animals, and possess primary reinforcing properties. Reward and punishment systems respond sensitively to withdrawal from DAP or antagonist administration. Catecholaminergic and peptidergic processes are of importance in the mechanisms of the emotionally positive action of DAP.