PSYC 211 Lecture Notes - Lecture 44: Drug Paraphernalia, Incentive Salience, Mesolimbic Pathway

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

Document Summary

Self-administration studies: animals quickly learn to press a level to get an injection of drug (self-adminstration), and develop a physical dependence to it, they will show withdrawal symptoms when the drug is removed. The lever press response is extinguished by replacing the drug with saline. The rat starts to level press again craving that motivates drug-seeking behaviour in former addicts. Mesolimbic system: addictive drugs (e. g. pcp, cannabis, amphetamine, cocaine, etc. ) trigger the release of dopamine in the nucleus accumbens. If dopamine transmission is blocked in the nucleus accumbens, a free shot of drug will not reinstate level press responses: the sight of smoking related images produces greater activation in the nucleus accumbens in smokers. Prefrontal cortex activation is inversely related to the amount of cocaine consumed each week: prefrontal cortex is less activated when addicts are performing tests of frontal function, and they perform poorly.