PSYC 311 Chapter Notes - Chapter 18.3: Striatum, Heredity, Reinforcement
9 Jun 2016
School
Department
Course
Professor
Document Summary
The release of dopamine in the nac leads to acquisition of a drug addiction, but changes sin the dorsal striatum are responsible for the establishment of the drug-taking habit. Drug users are noted to be withdrawn and apathetic in drug-free environments, but aroused and motivated when seeking a drug. Most people who are exposed to addictive drugs do not actually become addicted. Two peptides, orexin and mch play a crucial role in the reinforcing effects of drugs. We already know that orexin plays an important role in the control of sleep stages and food-seeking behaviour. It is synthesized by neurons in the lateral hypothalamus, and released in many parts of the brain, including regions that play a role in addiction such as the vta, nac and dorsal striatum. The administration of drugs or the presence of drug-related stimuli activates orexinergic neurons, and infusing orexin into the vta reinstates extinguished drug-seeking behaviours.
