Psychoactive Drugs
Psychoactivity and
Dependence
Psychoactive Drug
• A chemical substance that alters perceptions,
mood, or behavior
• Three common psychoactive drugs:
– Caffeine
– Alcohol
– Nicotine
• Induce an altered state of consciousness
Substance Abuse
• Recurrent drug use that results in disruption of
academic, social, or occupational functioning or in
legal or psychological problems
Drug Abuse – Do I have a problem?
Addiction
• Addiction – person craves & uses drug
despite its bad consequences on their
life
• Common Properties of Addiction:
– Physical dependence
– Tolerance
– Withdrawal symptoms
– Drug rebound effect
Dependence
• A physical and/or psychological need to take more of a
substance/drug after each continued use.
• Physical Dependence – drug is needed in order to function
normally
– Physical withdrawal symptoms occur when drug not in
system.
– Happens to habitual users
• Psychological Dependence – Taking the drug becomes part of
routine or habit that creating a psychological “need” for the
drug.
Tolerance
• Reduced responsiveness to the dose of a drug
– Requires the user to increase the dosage to achieve effects
previously obtained by lower doses of the drug
– Brain chemistry is adapting to offset the drug effect
(neuroadaptation)
Withdrawal
• The discomfort and distress that follow when a
person who is dependent on a drug discontinues the
use of the drug
• Drug Rebound Effect -Withdrawal symptoms are
usually the opposite of the drug’s effects
– “For every action there is an equal and opposite reaction”
Why do people abuse drugs?
Biopsychosocial Theory
Drugs and Neurotransmission
Psychoactive Drugs and Synapses
• Psychoactive drugs affect synapses and
neurotransmitters in three ways:
– Binding with receptor sites (mimics)*
– Blocking receptor site
– Blocking neurotransmitters’ reuptake*
* Increase the likelihood of the
receiving neuron firing
Drug Classifications
Psychoactive Drug Categories
• Four different categories we will study:
1. Depressants – depress, inhibit brain activity
2. Opiates – Similar to morphine, produce
feelings of euphoria & reduce pain
3. Stimulants – excite brain activity
4. Psychedelic/Hallucinogens/Marijuana – distort
sensory perceptions.
Drug Classifications:
Depressants
Depressants
• Drugs that reduce neural activity and slow
body functioning
• Includes:
– Alcohol—CNS depressant
– Barbiturates—induce sleep
– Tranquilizers—relieve anxiety
– Opiates
Alcohol
• Found in beer, wine, and liquor
• Slows thinking, and impairs physical activity
• The second most used psychoactive drug (caffeine first)
Euphoric Affects of Alcohol
• Disinhibitor - Alcohol impairs the parts of the brain
responsible for controlling inhibitions and making
judgments
• Results in less self-awareness, self-control and sometimes
more aggressive behavior.
• Also depends on environment and expectations
(Expectancy Effects).
What do we mean by “one drink?”
One 12-ounce can of beer
4 ounces of wine
1 ounce of whiskey
Blood Alcohol Content
(BAC)
• A measure of how much
alcohol is in a person’s
bloodstream
• BAC of .08 considered
legal intoxication in
most states
Alcohol, Memory, and Sleep
• Studies have shown that alcohol impairs memory by
suppressing the processing of events into long term
memory.
• Alcohol impairs REM sleep, further disrupting memory
storage.
• Also impairs speech and physical functioning.
• Death can occur if the brain’s respiratory center is slowed
so much it can no longer function.
Alcohol’s Affect on the Brain
Alcoholism damages the brain
Fetal Alcohol Syndrome
Never Drink When Pregnant
Sedatives
• Drugs that reduce anxiety or induce sleep
• Also called tranquilizers
• Include barbiturates and benzodiazepines
Barbiturates
• Depress the activity of the central nervous system
and thereby reduce anxiety (Phenobarbital)
• Can be lethal in overdose and interact with other
drugs, especially alcohol
• Impair both memory and judgment
• Can create tolerance and physical & mental
dependence
• Withdrawal can cause REM rebound nightmares,
hallucinations, disorientation and even lifethreatening convulsions.
Benzodiazepines/Tranquilizers
• Drugs that depress that activity of the
central nervous system without most of
the side effects associated with
barbiturates
• Help to reduce anxiety
• Include Valium and Xanax
• Can create dependency
Inhalants
• Chemicals that are inhaled to alter
consciousness.
• Paint, glue, gasoline, nitrous oxide &
aerosol sprays.
• Low doses may relax and reduce inhibition
• High doses can cause hallucinations and
loss of consciousness.
• Toxic to the liver and other organs.
Addiction and Depressants
• Play “Depressants and Their Addictive
Effect on the Brain” (4:24)
– Segment #22 from The Mind DVD
• How does withdrawal occur?
• What’s happening to the neurons of an
addict?
• How are these drugs suppressing the
nervous system?
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Opiates/Narcotics
Drugs that depress neural activity, temporarily lessen
pain and anxiety and produce feelings of euphoria
Mimic Endorphins to produce numbing of pain and
good feeling
• This causes brain to produce less in response so
withdrawal is extremely difficult.
Include: opium, morphine, heroin, methadone,
Percodan, Demerol
Drug Classifications:
Stimulants
Stimulants
• Drugs that excite neural activity and speed up body
functions
• Include: caffeine, nicotine, amphetamines, and cocaine
• All are at least mildly addictive.
• Used to feel alert, lose weight, boost mood or improve
athletic performance
Caffeine
• Stimulant found in coffee, chocolate, tea, and some soft
drinks
• Provides user with a sense of increased energy, mental
alertness, and forced wakefulness
• Blocks neurological receptor sites that if activated, sedate
the central nervous system
• Withdrawal symptoms are sleepiness, fatigue, anxiety,
insomnia, increased heart rate.
Nicotine
• Stimulant found in tobacco
• Effects similar to those of caffeine – reduces fatigue &
drowsiness and increases mental alertness (epinephrine &
norepinephrine)
• Affects various areas in the brain affecting mood,
decreasing anxiety & reducing pain (Dopamine & Opioids)
• Very addictive and does not stay in the body very long
– Only takes 7 seconds for nicotine to act on the brain after inhaling
• See video clip on nicotine addiction.
• Stimulant derived from leaves of the coca plant
• Crack – cocaine crystals
• Blocks the reuptake of certain neurotransmitters
– Dopamine, Serotonin & Norepinephrine
• Dependency is quick and severe; places extreme strain on
cardiovascular system
– See the story of Len Bias (4 min)
• Can cause cocaine psychosis – schizophrenia-like symptoms
including auditory hallucinations & paranoia, “cocaine
bugs” or tactile hallucinations
How Cocaine Works
Amphetamines/Meth
• Drugs that stimulate neural activity, speeding up body
functions, with associated energy and mood changes
• Includes: speed, uppers, and methamphetamines
• Mimic adrenaline & dopamine
• Can cause irreversible changes in mood & function by
reducing dopamine receptors & transporters.
• Withdrawal causes fatigue, deep sleep, intense depression,
increase in appetite.
The Faces Of Meth
http://www.anti-meth.org/photos2.html
“Club” Drugs/Ecstasy
• Hallucinogenic drug that produces lower
inhibitions, pleasant feelings, and greater
acceptance of others
• Also called MDMA
• Blocks serotonin reuptake prolonging its
“good” feeling
• Even moderate users may experience
permanent brain damage to serotonin nerve
endings & even memory and verbal
reasoning problems up to a year later.
• Dehydration, rapid heartbeat, tremors, muscle
tension, teeth clenching & high body temp
can result.
Drug Classifications:
Hallucinogens
Hallucinogens/Psychedelic Drugs
• Drugs that distort perceptions and create
sensory images even when there is no
sensory input
• Include: LSD, Mescaline and Marijuana
Lysergic Acid Diethylamide (LSD)
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Powerful hallucinogenic drug
Also known as “acid”
The effects vary from person to person
Users can be dangerous to themselves and others.
Mimics & blocks the reuptake of serotonin.
Flashbacks, psychotic reactions can occur.
Hallucinogen Affect
Hallucination - like patterns Geometric forms, similar to
those experienced by drug users during drug - induced
hallucinations, can be seen in the embroidery of the
Huichol. These Mexican Indians used peyote, from
which the hallucinogen mescaline derives.
Marijuana
• Leaves, stems, resin, and flowers form the hemp plant
• When smoked, lower inhibitions and produce feelings of
relaxation and mild euphoria
• Increases sensitivity to colors, sounds, tastes & smells
• THC (delta-9-tetrahydrocannabinol) is the active ingredient.
– Causes animals to misjudge events (rats forget how to run
maze)
– Stays in the body for a week or more
• Disrupts memory; lung damage from smoke, heavy use for many
years can shrink brain areas associated with memory and emotion
• Withdrawal may cause insomnia, tremors and decreased appetite.
• Is helpful in decreasing nausea and reducing effects of glaucoma.
Drug Use
(2007 National Survey on Drug Use and Health)
Drug Use
Treatment
• Play “Treating Drug Addiction: A Behavioral
Approach” (19:40)
– Segment #30 from The Mind: DVD
– Watch if time allows.
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What become “triggers” for addicts?
How do addicts’ bodies react to “triggers?”
Describe how this treatment works.
Describe what withdrawal/addiction is like?
What do brain scans show about addicts’
brains?