Stimulants

Stimulants speed up signals passing through the nervous system; they activate organs and functions of the body, heighten arousal, increase overal behavioral activity, and suppress fatigue. In low doses, stimulants can heighten the body's sensitivity and improve mental and physical performance. At high doses, however, many of these functions seem to go haywire. Behavior becomes unfocused, supersensitivity translates easily into paranoia, and mental and intellectual performance become uncontrollable. ineffective, often compulsively repetitive.

The immediate subjective effect of the stimulants is euphoria and a sense of confidence and well-being. As I pointed out in Chapter 2, of all drugs or drug types, cocaine and the amphetamines are the two with the greatest immediate sensual appeal —that is, experimental subjects, without knowing what drug they have taken, enjoy their effects most and would rather take them again than any other drug. In experiments, rats, mice, and monkeys will selfadminister cocaine in preference to food, and will even starve to death self-administering cocaine. If experimental animals receive cocaine as a result of engaging in a certain activity, and the researchers then discontinue administering the drug, these animals will go on engaging in that activity— thousands of times in an hour—at a higher rate than for any other drug type . In psychological terms, then, cocaine and the amphetamines are powerfully reinforcing. People (and animals) enjoy their effects. It should come as no surprise that they are widely used for recreational purposes—to get high.