PSY290H5 Chapter Notes - Chapter 15: Fetal Alcohol Spectrum Disorder, Drug Tolerance, Drug Withdrawal
Document Summary
Chapter #15: drug addiction and the brain"s reward circuit. Drug tolerance: decreased sensitivity to a drug as a result of exposure to it: dose of drug has less of a effect, so it takes more of the drug to produce the same effect. Three main points to drug tolerance: cross tolerance, drug tolerance develops to some effects of a drug but not to others. Drug sensitization: increasing sensitivity to a drug: not a single mechanism to drug tolerance, many different adaptive changes occur to reduce effects. Two categories of changes underlie drug tolerance: metabolic tolerance: reduced amount of the drug getting to its site of action, functional tolerance: changes that reduce the reactivity of the sites of action. Tolerance to psychoactive drugs is mainly functional. Exposure to drugs can reduce the number of receptors for it, decrease efficiency of binding, diminish impact of receptor binding to activity of the cell.
