UNIT 2: Biological Bases of Behavior
PART II: States of Consciousness
Learning Targets
18-1 Describe substance abuse disorders.
18-2 Discuss the roles that tolerance and addiction play in substance use disorders, and how the concept of addiction has changed.
18-3 Identify the depressants, and describe their effects.
18-4 Identify the stimulants, and describe their effects.
18-5 Identify the hallucinogens, and describe their effects.
What are psychoactive drugs and �what is a substance abuse disorder?
psychoactive drugs
chemical substances that alter perceptions and moods
substance abuse disorder
a disorder characterized by continued substance craving and use despite significant life disruption and/or physical risk
When is drug use a disorder?
How many of the 11 statements above do you think someone would have to agree with in order to be diagnosed with a substance abuse disorder?
How many did you guess?
On the previous slide, how many indicators did you think were needed to diagnose substance abuse disorder?
The severity of substance use disorder varies from
mild (two to three of the indicators) to
moderate (four to five indicators) to
severe (six or more indicators).
American Psychiatric Association, 2013.
What are tolerance and addiction?
tolerance
the diminishing effect
with regular use of the same dose of a drug, requiring the user to
take larger and larger doses before experiencing the drug’s effect
addiction
a primary, chronic disease of brain reward, motivation, memory and related circuitry
How is addiction characterized?
Addiction is characterized by inability to consistently abstain, impairment in behavioral control, craving, diminished recognition of significant problems with one’s behaviors and interpersonal relationships, and a dysfunctional emotional response.
Despite the adverse consequences of using the drug, people in the grip of addiction want the drug more than they like the drug.
How can tolerance lead to a �substance abuse disorder?
Due to neuroadaptation, brain chemistry changes to offset the effects of the drug. Users require larger and larger doses which increases the risk of becoming addicted and developing a substance abuse disorder.
What is withdrawal?
the discomfort and
distress that follow discontinuing
an addictive drug or behavior
Most ex-smokers have kicked the habit on their own.
Newport, 2013.
How has the concept of addiction changed?
Some behaviors can become compulsive and dysfunctional—
similar to problematic alcohol and drug use.
The DSM5 classifies gambling disorder but
some behavior addictions require more study, such as internet gaming disorder,
and internet use addictions.
What are the three major categories of psychoactive drugs?
1
depressants
2
stimulants
3
hallucinogens
AP® Exam Tip 1
These three categories — depressants, stimulants, and hallucinogens — are important.
There are likely to be questions on the AP® exam that will require you to know how a particular psychoactive
drug is classified and what affect the drug has on the body.
What are depressants and �what are their effects?
drugs (such as alcohol, barbiturates, and opiates)
that reduce neural activity and
slow body functions
Alcohol
Alcohol is a central nervous system (CNS) depressant meaning it slows neural activity in the brain and spinal cord.
How does alcohol interact with neurotransmitters?
GABA, an inhibitory neurotransmitter, and glutamate, an excitatory neurotransmitter, both interact with alcohol to produce the effects we associate with drinking.
Alcohol and GABA
When alcohol enters the body, it acts as an agonist with inhibitory GABA receptors making them more inhibitory.
Alcohol and glutamate
Alcohol acts as an antagonist to glutamate receptors and prevents glutamate from exciting the cell.
How does alcohol use disorder �change the structure of the brain?
MRI scans show brain shrinkage(enlarged ventricles) in women with alcohol use disorder (left) compared with women in a control group (right).
How does alcohol impair reaction time?
Slowed neural processing causes reactions to slow, speech to slur, and skilled performance to deteriorate.
What does research show about human’s awareness of drunken states?
When drunk, people aren’t aware how drunk they are.
(Moore et al., 2016).
Virtually all drinkers who
had insisted when sober that they would not
drive under the influence later decided to drive home from a bar, even if given a Breathalyzer test and told they were intoxicated.
(Denton & Krebs, 1990; MacDonald et al., 1995)
How does alcohol impair memory and self-awareness?
memory disruption
Alcohol can disrupt memory formation, and heavy drinking can also
have long-term effects on the brain and cognition.
Alcohol suppresses REM sleep, which is needed for memory consolidation.
reduced self-awareness
Those who consume alcohol are more likely to be caught mind-wandering yet not realize they had.
People who want to suppress their awareness of failures or shortcomings are more likely to drink.
What are expectancy effects?
Expectations influence behavior.
Simply believing we’re consuming alcohol can cause us to act out alcohol’s presumed influence.
(Christiansen et al., 2016; Moss & Albery, 2009)
What are barbiturates?
drugs that depress
central nervous system activity, reducing anxiety but impairing memory and judgment
Barbiturates such as Nembutal, Seconal and Amytal are sometimes prescribed to induce
sleep or reduce anxiety.
In larger doses, they can impair memory and judgment. If combined with alcohol, the total depressive effect on body functions can be lethal.
What are opiates?
Opium and its derivatives, such as morphine and heroin; depress neural activity, temporarily
lessening pain and anxiety.
As blissful pleasure replaces pain and anxiety, the user’s pupils constrict, breathing slows, and
the person becomes lethargic.
Those who become addicted to this short-term pleasure may pay a long-term price: a gnawing craving for another fix, a need for progressively larger doses (as tolerance develops), and the extreme discomfort of withdrawal.
How can an opiate addiction lead to death?
When repeatedly flooded with an artificial
opiate, the brain eventually stops producing endorphins, its own opiates. If the artificial opiate
is then withdrawn, the brain will lack the normal level of these painkilling neurotransmitters.
In recent years, more and more people have been unable or unwilling to tolerate this state and
have paid an ultimate price — death by overdose.
(CDC, 2015)
1. What Would You Answer?
Slowed reactions, slurred speech, and decreased skill performance are associated with abuse of which drug?
What are stimulants and �what are their effects?
drugs (such as caffeine, nicotine, and the more
powerful cocaine, amphetamines,
methamphetamine, and Ecstasy)
that excite neural activity and speed up body functions
Why use stimulants?
People use
stimulants to feel alert, lose weight, or boost mood or athletic performance.
What is nicotine?
a stimulating and highly
addictive psychoactive drug found in tobacco
Tobacco products include cigarettes, cigars, chewing tobacco, pipe tobacco, snuff, and e-cigarettes (vaping).
Let’s look at the research on tobacco use…
Smoke a cigarette and nature will charge you 12 minutes — ironically, just about the length of time you spend smoking it.
(Discover, 1996)
Compared with nonsmokers, smokers’ life expectancy is “at least 10 years shorter”.
(CDC, 2013)
By 2030, annual tobacco deaths are expected to increase to 8 million. That means that 1 billion twenty-first-century people may be killed by tobacco.
(WHO, 2012)
How teens keep the cigarette industry in business.
Virtually nobody starts smoking past the vulnerable teen
years. Eager to hook customers whose
addiction will give them business for
years to come, cigarette companies
target teens.
Portrayals of smoking by popular actors, such as Scarlett Johansson in Hail, Caesar!, tempt teens to imitate.
Let’s pause for a quote…
Humorist Dave Barry (1995) recalling why he smoked his first cigarette the summer he turned 15:
“Arguments against smoking: ‘It’s a repulsive addiction that slowly but surely turns you into a gasping, gray-skinned, tumor-ridden invalid, hacking up brownish gobs of toxic waste from your one remaining lung.’
Arguments for smoking: ‘Other teenagers are doing it.’ Case closed! Let’s light up!”
What are the physiological effects of nicotine?
Nicotine reaches the brain within 7 seconds, twice as fast
as intravenous heroin.
Within minutes, the amount in the blood soars.
What is cocaine?
a powerful and addictive stimulant derived from the coca plant; produces temporarily increased alertness and euphoria
Cocaine is snorted, injected, or smoked.
It enters the bloodstream quickly, producing a rush of euphoria that depletes the brain’s supply of the neurotransmitters dopamine, serotonin, and norepinephrine.
A quick refresher on neural transmission.
Neurotransmitters carry a message from a
sending neuron across a synapse to receptor
sites on a receiving neuron.
What happens next?
The sending neuron normally reabsorbs
excess neurotransmitter molecules, a
process called reuptake.
How does cocaine impact normal neural transmission?
By binding to the sites that normally reabsorb
neurotransmitter molecules, cocaine blocks reuptake of dopamine, norepinephrine, and
serotonin.
(Ray & Ksir, 1990)
How does this produce euphoria?
The extra neurotransmitter molecules remain in the synapse, intensifying their normal mood-altering effects and producing a euphoric rush.
When the cocaine level drops, the absence of these neurotransmitters produces a crash.
AP® Exam Tip 2
Many of the slides in this Module are an excellent review of how neurotransmitters work.
If there is any part of this that you don’t understand, head back to Module 9 for a complete explanation.
Neural communication is a topic that has been
on the AP® exam.
What is methamphetamine?
a powerfully addictive drug that stimulates
the central nervous system, with accelerated body functions and associated energy and mood
changes; over time, appears to reduce baseline dopamine levels
“Meth’s” aftereffects may include irritability, insomnia, hypertension, seizures, social isolation, depression, and occasional violent outbursts.
What physical changes result with methamphetamine use?
In the 18 months between these two mug shots, this woman’s methamphetamine addiction led to
obvious physical changes.
What is Ecstasy(MDMA)?
a synthetic stimulant and mild hallucinogen
produces euphoria and social intimacy, but with short-term health risks and longer-term harm to serotonin-producing neurons and to mood and cognition
How does Ecstasy (MDMA) work?
As an amphetamine derivative, Ecstasy (MDMA) triggers dopamine release, but its major effect is releasing stored serotonin and blocking its reuptake, thus prolonging serotonin’s feel-good flood.
Let’s look at the research on �Ecstasy (MDMA)…
Ecstasy’s dehydrating effect, can lead to severe overheating, increased blood pressure, and death.
Long-term, repeated leaching of brain serotonin
can damage serotonin-producing neurons, leading to decreased output and increased risk of permanently
depressed mood.
(Croft et al., 2001; McCann et al., 2001; Roiser et al., 2005)
Ecstasy also suppresses the immune system, impairs memory, slows thought, and disrupts sleep.
(Laws & Kokkalis, 2007; Schilt et al., 2007; Wagner et al., 2012).
2. What Would You Answer?
Which stimulant causes high energy and emotional elation, dehydration, and damage to serotonin producing neurons?
B. nicotine
C. ecstasy
D. caffeine
What are hallucinogens and �what are their effects?
psychedelic (“mind-manifesting”) drugs, such
as LSD, that distort perceptions and evoke sensory images in the absence of sensory input
What are hallucinations and �near-death experiences?
hallucinations
distorted perceptions and sensory images in the absence of sensory
input
near-death experiences
an altered state of consciousness
reported after a close brush with death (such as cardiac arrest);
often similar to
drug- induced
hallucinations
What is LSD?
a powerful hallucinogenic drug; also known as acid (lysergic acid diethylamide)
The emotions of an LSD (or acid) trip vary from euphoria to detachment to panic. Users’
mood and expectations (their “high hopes”) influence the emotional experience, but the perceptual distortions and hallucinations have some commonalities.
What is marijuana (cannabis) and �what is THC?
Marijuana (cannabis) is usually classified as a mild hallucinogen because it amplifies sensitivity to colors, sounds, tastes, and smells.
But like alcohol, marijuana also relaxes, disinhibits, and may produce a euphoric high. Marijuana leaves and flowers contain THC (delta-9-tetrahydrocannabinol), the psychoactive ingredient.
Whether smoked or eaten THC produces a
mix of effects.
Take a moment to review the psychoactive drugs.
3. What Would You Answer?
Which drug is incorrectly matched with its category?
Learning Target 18-1 Review
What are substance use disorders?
Learning Target 18-2 Review
What roles do tolerance and addiction
play in substance use disorders?
Learning Target 18-3 Review
What are depressants, and
what are their effects?
Learning Target 18-4 Review
What are the stimulants and
what are their effects?
Learning Target 18-5 Review
What are hallucinogens and
what are their effects?