PSYC 211 Lecture Notes - Lecture 62: Nucleus Accumbens, Drug Paraphernalia, Incentive Salience

• School: McGill University
• Department: Psychology
• Course: PSYC 211
• Professor: Yogita Chaudasama

Document Summary

Negative reinforcement increases the frequency of behavior because of the removal of an aversive stimulus: e. g. a rat will press a lever (the behavior) to prevent the occurrence of a foot shock (the aversive stimulus) People who are physically dependent on drugs show: tolerance a decreased sensitivity to the drug due to continued use, withdrawal symptoms opposite effects of the drug itself when the person stops taking the drug. Positive reinforcement provokes drug taking in the first place but negative reinforcement ensures that withdrawal effects go away. When an addictive drug activates the mesolimbic dopaminergic system, it gives incentive salience to the stimuli that are present at the time of drug taking. ( e. g. drug paraphernalia (bong, pipe, syringe, spoon, mirror, razor blade). Stimuli with incentive salience elicit craving or wanting (robinson and berridge, 2003). Animals quickly learn to press a lever to get an injection of drug (self-administration), and develop a physical dependence to it.