Transcript Psychology

Thinking About Psychology:
The Science of Mind and
Behavior
Charles T. Blair-Broeker
Randal M. Ernst
Module 22
Drugs
Module 22: 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
Dependence
• A state of physiological and/or
psychological need to take more of a
substance after continued use.
• Withdrawal follows if the drug is
discontinued
Withdrawal
• The discomfort and distress that follow
when a person who is dependent on a
drug discontinues the use of the drug
• Withdrawal symptoms are usually the
reverse of the drug’s effects.
Tolerance
• Reduced responsiveness to a drug,
prompting the user to increase the
dosage to achieve effects previously
obtained by lower doses of the drug
Tolerance
Module 22: Drugs
Drugs and
Neurotransmission
Neurotransmission
• The process whereby neurons
communicate with each other
• Neurotransmission, especially in the
brain and spinal cord, helps explain the
effects of psychoactive drugs.
• Psychoactive drugs interfere with
normal neurotransmission.
Neurotransmitters
• Chemical messengers that cross synaptic
gaps between neurons
• When released by the sending neuron,
neurotransmitters travel across the
synapse and bind to receptor sites on the
receiving neuron, setting up the next
link in the chain of communication.
Synapse
• The junction between the tip of the
sending neuron and the receptor sites on
the receiving neuron
• Call the synaptic gap or cleft
Neural Activity
Neurotransmitters and the Synapse
Reuptake
• Process where the unused
neurotransmitter chemical is reabsorbed
by the sending neuron
Reuptake
Psychoactive Drugs and Synapses
• Psychoactive drugs affect synapses and
neurotransmitters in three ways:
– Binding with receptors
– Blocking receptor site
– Blocking neurotransmitters’ reuptake
Module 22: Drugs
Drug Classifications
Five Psychoactive Drug Categories
• Five different categories we will study:
– Depressants
– Opiates
– Stimulants
– Hallucinogens
– Marijuana
Module 22: Drugs
Drug Classifications:
Depressants
Depressants
• Drugs that reduce neural activity and
slow body functioning
• Includes alcohol and sedatives
Alcohol (ethyl alcohol)
• Found in beer, wine, and liquor
• The second most used psychoactive
drug (caffeine first)
• Slows thinking, and impairs physical
activity
Blood Alcohol Content (BAC)
• A measure of how much alcohol is in a
person’s bloodstream
• BAC of .8 considered legal intoxication
in most states
Euphoric Affects of Alcohol
• Alcohol impairs the parts of the brain
responsible for controlling inhibitions
and making judgments
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.
Sedatives
• Drugs that reduce anxiety or induce
sleep
• Also called tranquilizers
• Include barbiturates and
benzodiazepines
Barbiturates
• Drugs that depress the activity of the
central nervous system and thereby
reduce anxiety
• Can be lethal in overdose and interact
with other drugs, especially alcohol
• Impair both memory and judgment
• Can create tolerance and dependence
Benzodiazepines
• Drugs that depress that activity of the
central nervous system without most of
the side effects associated with
barbiturates
• Include Valium and Xanax
• Can create dependency
Module 22: Drugs
Drug Classifications:
Opiates
Opiates
• Drugs that depress neural activity,
temporarily lesson pain and anxiety
• Include: opium, morphine, and heroin
Morphine
• Strong sedative and pain-relieving drug
derived from opium
• Works by preventing pain neurons from
firing or releasing pain-signaling
neurotransmitters into the synapse
Endorphins
• Natural, opiate-like neurotransmitters
linked to pain control and to pleasure
• Body’s natural pain killers
Endorphins
• Play “Endorphins: The Brain’s Natural
Morphine” (5:01) Segment #5 from The
Mind: Psychology Teaching Modules
(2nd edition).
Module 22: Drugs
Drug Classifications:
Stimulants
Stimulants
• Drugs that excite neural activity and
speed up body functions
• Include: caffeine, nicotine,
amphetamines, and cocaine
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
Nicotine
• Stimulant found in tobacco
• Effects similar to those of caffeine
• Very addictive and does not stay in the
body very long
Cocaine
• Stimulant derived from leaves of the
coca plant
• Crack – cocaine crystals
• Blocks the reuptake of certain
neurotransmitters
• Dependency is quick and severe; places
extreme strain on cardiovascular system
Amphetamines
• Drugs that stimulate neural activity,
speeding up body functions, with
associated energy and mood changes
• Includes: speed, uppers, and
methamphetamines
• Mimic adrenaline
• Can cause irreversible changes in mood
Module 22: Drugs
Drug Classifications:
Hallucinogens
Hallucinogens
• Drugs that distort perceptions and evoke
sensory images in the absence of
sensory input
• Include: LSD and ecstasy
• Sometimes called “psychedelics”
Lysergic Acid Diethylamide (LSD)
•
•
•
•
Powerful hallucinogenic drug
Also known as “acid”
The effects vary from person to person
Users can be dangerous to themselves
and others.
Ecstasy
• Hallucinogenic drug that produces lower
inhibitions, pleasant feelings, and
greater acceptance of others
• Also called MDMA
• Even moderate users may experience
permanent brain damage.
Module 22: Drugs
Drug Classifications:
Marijuana
Marijuana
• Leaves, stems, resin, and flowers form
the hemp plant that, when smoked,
lower inhibitions and produce feelings
of relaxation and mild euphoria
• THC (delta-9-tetrahydrocannabinol) is
the active ingredient
• Disrupts memory; lung damage from
smoke
Module 22: Drugs
Prevention
High School Drug Use
(Johnston & others, 2002)
Treatment
• Play “Treating Drug Addiction: A
Behavioral Approach” (19:40) Segment
#30 from The Mind: Psychology
Teaching Modules (2nd edition).
The End