A drug is a chemical substance produced exogenously (outside of the body) that, when taken into the body, changes normal body functions. Psychologists are very interested in psychoactive drugs that change central nervous system (CNS; brain and spinal cord) activity, and thereby affect perception, thought, emotion, and behavior. Although people use many psychoactive drugs for acceptable medicinal reasons (see Chapter 18), this chapter focuses on those psychoactive drugs that people use primarily for recreational, nonmedicinal reasons (e.g., to feel good, be more alert, alter or avoid reality). An adult drinking alcohol to relax or smoking cigarettes to stop the jitters are examples of recreational use of licit (legal) drugs in this country, and smoking crack to feel euphoric or injecting ...
Drugs and Behavior
Drugs and behavior