Drugs & the Brain Psychology
Psychoactive Drugs • Chemical substances that alter perceptions and moods • Three categories: • Depressants • Stimulants • Hallucinogens
Depressants • Drugs that reduce neural activity and slow body functions • Examples • Alcohol • Barbiturates or tranquilizers (prescription drugs used to induce sleep or relieve anxiety) • Opiates (heroin, morphine)
Depressants • Effects • Disinhibition (less likely to hold back) • Slowed neural processing • Memory disruption • Reduced self-awareness & self-control
Stimulants • Excite neural activity and speed up bodily functions • Examples • Caffeine • Nicotine (cigarettes) • Amphetamines (cocaine, ecstasy) • Methamphetamine (speed)
Stimulants • Effects • Increased heart rate & breathing • Causes pupils to dilate • Diminished appetite • Increased energy & self-confidence
Hallucinogens • Distort perceptions and evoke sensory images in the absence of sensory input. • Examples • LSD • Marijuana
Marijuana • Impairs motor coordination, perceptual skills, and reaction time necessary to operate a car or other machine. • Disrupts memory formation and interferes with immediate recall of information learned a few minutes before. • Prenatal exposure impairs brain development.