1. Drugs and Consciousness  Psychoactive Drug  chemical substance alters perceptions and mood  Physical Dependence  physiological need for drug  marked by unpleasant withdrawal symptoms  Psychological Dependence  psychological need to use drug  ie: to relieve negative emotions

2. Dependence and Addiction  Tolerance  diminishing effect with regular use  Withdrawal  discomfort and distress that follow discontinued use Small Large Drug dose Little effect Big effect Drug effect Response to first exposure After repeated exposure, more drug is needed to produce same effect

3. Psychoactive Drugs  Depressants  drugs that reduce neural activity  slow body functions  alcohol, barbiturates, opiates  Stimulants drugs that excite neural activity speed up body functions  caffeine, nicotine, amphetamines, cocaine

4. Psychoactive Drugs  Hallucinogens  psychedelic drugs that distort perceptions  evoke sensory images in absence of sensory input  LSD  Barbiturates  drugs that depress activity of central nervous system, reducing anxiety but impairing memory and judgment

5. Psychoactive Drugs  Opiates  opium and derivatives (morphine/heroin)  opiates depress neural activity, temporarily lessen pain and anxiety  Amphetamines drugs that stimulate neural activity, causing speeded-up body functions and associated energy and mood changes

6. Cocaine Euphoria and Crash

7. Trends in Drug Use 1975 ‘77 ‘79 ‘81 ‘83 ‘85 ‘87 ‘89 ‘91 ‘93 ‘95 ‘97 ‘99 Year 80% 70 60 50 40 30 20 10 0 High school seniors reporting drug use Alcohol Marijuana/ hashish Cocaine

8. Perceived Marijuana Risk ‘75 ‘77 ‘79 ‘81 ‘83 ‘85 ‘87 ‘89 ‘91 ‘93 ‘95 ‘97 ‘99 Year 100% 90 80 70 60 50 40 30 20 10 0 Percent twelfth graders Perceived “great risk of harm” in marijuana use Used marijuana