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

Dependence and Addiction Tolerance

diminishing effect with regular use

Withdrawal discomfort

and distress that follow discontinued use

Small Large

Drug dose

Littleeffect

Bigeffect

Drugeffect

Response tofirst exposure

After repeatedexposure, moredrug is neededto produce same effect

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

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

Psychoactive Drugs

Opiates opium and derivatives (morphine/heroin) opiates depress neural activity, temporarily

lessen pain and anxiety

Amphetaminesdrugs that stimulate neural activity, causing speeded-up body functions and associated energy and mood changes

Cocaine Euphoria and Crash

Trends in Drug Use

1975 ‘77 ‘79 ‘81 ‘83 ‘85 ‘87 ‘89 ‘91 ‘93 ‘95 ‘97 ‘99Year

80%

70

60

50

40

30

20

10

0

High schoolseniors

reportingdrug use

Alcohol

Marijuana/hashish

Cocaine

Perceived Marijuana Risk

‘75 ‘77 ‘79 ‘81 ‘83 ‘85 ‘87 ‘89 ‘91 ‘93 ‘95 ‘97 ‘99Year

100%

90

80

70

60

50

40

30

20

10

0

Percenttwelfth

graders

Perceived “great risk ofharm” in marijuana use

Used marijuana