Drugs

Influences on Drug Use• Biological – heredity

– Identical twins– Adoption studies– Boys at age 6 excitable, fearless, impulsive (genetic traits) are

more likely to take drugs– NPY – brain chemical more sensitive to alcohol– Gene identified to predispose people to alcohol dependence

• Psychological – Lacking sense of purpose– Stress– Depression

• Social-cultural– Urban enviro– Cultural attitude toward drugs– Peer influences

Drugs• Our brain is

protected by a layer of capillaries called the blood-brain barrier.

• The drugs that are small enough to pass through are called psychoactive drugs.

Psychoactive Drugs

Psychoactive Drugs - Chemicals that alter moods and perceptions through actions on neural synapses• Altered state (altered moods and

perceptions)associated with changes in brain activity

Examples: alcohol, marijuana, cocaine (depressants, hallucinogens, stimulants)

Dependence and Addiction• Addiction – compulsive craving for a drug despite

adverse consequences– What about each of our three major types of drugs

make someone want to keep taking them?• Sense of well-being, feeling of euphoria , blissful pleasure, relief

from anxiety, increased self-confidence, alertness• Withdrawal symptoms can contribute to addiction

• Tolerance – need to take larger and larger doses to experience the same effects– Neuroadaptation - change in brain chemistry that offsets

the effects of a psychoactive drug

• Withdrawal – discomfort and distress that follow the discontinued use of certain drugs (aches, nausea, distress)

• Physical dependence – physiological need for a drug indicated by withdrawal symptoms

• Psychological dependence – psychological need to use a drug

Drugs are either….

• Agonists – mimics neurotransmitters• Opiates (heroine,

morphine) mimic endorphins

• Antagonists – block neurotransmitters• LSD – blocks serotonin

• Reuptake inhibitors• Cocaine – blocks

reuptake of dopamine, Ecstasy blocks reuptake of serotonin

Depressants

• Slows down body processes and calms neural activity.– Breathing slows,

pupils constrict, anxiety replaced by pleasure

• Alcohol• Barbiturates/

tranquilizers• Opiates (morphine,

heroine)

Alcohol

• More than 86 billion dollars are spent annually on alcoholic beverages.

• Alcohol is involved in 60% of ALL crimes.

• Alcohol is involved in over 70% of sexually related crimes.

• Is it worth the cost?

Opiates• Agonist for endorphins. • Morphine, heroin,

methadone and codeine.• Pupils constrict,

breathing slows, lethargy, blissful pleasure replaces pain and anxiety

• Highly addictive• Brain stops producing

own opiates (endorphins)– brain will lack painkilling

neurotransmitters after withdrawal

Stimulants• Excite neural activity and

speed up body processes.– Increased heart and

breathing rates, pupils dilate, appetite diminishes, energy increases

• More powerful ones (like cocaine) give people feelings of invincibility.

• Amphetamines• Methamphetamines• Caffeine• Nicotine• Cocaine• Ecstasy

Hallucinogens

• Psychedelics• Causes changes in

perceptions of reality

• LSD, peyote, psilocybin mushrooms and marijuana.

• Reverse tolerance or synergistic effect

An altered state of consciousness in which people experience fantastic images and often feel separated from their bodies is most closely associated with the

use of

Hero

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Cocaine

Barbitu

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1. Heroin2. Cocaine3. Barbiturates4. Marijuana5. LSD

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Barbiturates are considered

Stimulants

Hallu

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Depre

ssants

Opiates

Both a depress.

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1. Stimulants2. Hallucinogens3. Depressants4. Opiates5. Both a depressant

and hallucinogen

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What do methamphetamine, caffeine and cocaine have in common?

They slow body..

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They excite ne...

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1. They slow body functions and calm neural activity

2. They depress neural functioning and reduce pain

3. The distort perceptions and evoke sensations without sensory input

4. They excite neural activity and arouse body function

5. They relax the body, lead to disinhibition and produce euphoria

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