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Alcohol and the Adolescent Brain
Ken Winters, Ph.D.Department of PsychiatryUniversity of [email protected]
U.S.E.D. Grants to Reduce Alcohol Abuse ConferenceNovember 18, 2003
U of Minnesota,Center for AdolescentSubstance Abuse Research
Staff are all above average.Women are strong.Men are good looking.
Our ex-Governor wasa professional wrestler
3. Adolescence and the Brain
4. Brain and Alcohol
5. Youth, Brainand Alcohol
Are adolescents more susceptible toalcohol than adults?
1. Developmental Issues 2. Brain Functioning
Is addiction a brain disorder?
6. Prevention and Treatment
1. Developmental Issues
Alcohol Use
Youth alcohol use occurs on a continuum
Most youth have used some alcohol
Alcohol Use by Youth
7 million teens binge
drink at least once a
month
Trends in prevalence of drugs for 12th graders: 1994 to 2001
30-Day Year Alcohol % 1994 50.1
1995 51.3
1996 50.8
1997 52.7
1998 52.0
1999 51.0 2000 50.0
2001 49.8
MTFS, 1975-2001
Alcohol Problems
Alcohol Use Disorders (AUDs)are Relatively Rare
AUD rates vary;3-10%
Most youthwho use donot meet criteria for abuse ordependence
boy AUD rates >girl AUD rates
Long-Term, Heavy Use of Alcohol
Significant shrinking of the brain
50% - 75% show cognitive impairment
Effects remain even after detoxification & abstinence
Alcohol dementia is 2nd-leading cause of adult dementia
Trends in prevalence of drugs for 12th graders: 1994 to 2001
Daily Year Cigarettes % 1994 19.4
1995 21.7
1996 22.2
1997 24.5
1998 22.5
1999 23.1 2000 20.5
2001 19.0 MTFS, 1975-2001
Marijuana: Trends in Perceived Availability, Perceived Risk, and Use for 12th Graders
0
20
40
60
80
100
1975 1977 1979 1981 1983 1985 1987 1989 1991 1993 1995 1997 1999 2001
Availability
Risk
Use
Per
cen
t
MTFS, 1975-2001
Availability= Fairly easy or very easy to getRisk = Great risk of harm in regular useUse= Once or more, past 30 days
Non-Medical Use of Prescription Drugs
• The rapid rise in use of club drugs, methamphetamine, and oxycodone has put a spotlight on the non-medical use of prescription drugs.• Increase by 11% in 2001
compared to previous year.• Exceeds combined use of heroin,
cocaine, crack and hallucinogens.
Comorbid Disorders with AUD
Alcohol UseDisorder
Depression
Gambling
OppositionalDefianceDisorder
Conduct Disorder
ADHD
Anxiety
Many predateonset of AUD
> comorbidity,>AUD
Relapse > ifcomorbidity Medication
maybe appropriate
•Individuation
•need to develop personal identity
•Separation•need to separate from parents
Developmental Phases of Adolescence
These forces can disrupt ourprevention and treatment efforts
Stages of ChangeProchaska and DiClimente
Relapse
Pre-contem.
ContemplationPreparation
Action
Maintenance
PrecontemplationAction
Prep
Pre-contem.
Contemplation
Stages of Change for Most Youth?
Precontemplation
Working with parents
1. Developmental Issues 2. Brain Functioning
What a Machine!
100 billion neurons in the brain
Cortex is 1/8 inch thick like bark – 80% of it is neurons
Fastest brain messages = 360 mph
Over 90 neurochemicals are involved in transmission of impulses across neurons
Brain Functioning
Humans are “wired” with nerve cells (neurons)
Neurons group together to form strands (up to 4 feet long)
Strands perform specific function
They extend from brain to spinal cord
Brain Functioning
Strands are not continuous - they have small spaces in between
Spaces are called synapses
Neurons pass messages through the synapse with chemicals
Chemicals are called neurotransmitters
Drugs affect neurotransmitters
“The 3 pound organ that rules the body is finally giving up its secrets”
(TIME, August, 2001)
1990’s information explosionMRIPETCAT
These brain imaging techniques produce windows to observe the effects of substances on the brain
Imaging Modalities
CT SPECT FDG PET Ligand PET
Anatomic MRIMR Spectroscopy fMRI Diffusion MRI
Your Brain on Alcohol
1-2 Min 3-4 5-6
6-7 7-8 8-9
9-10 10-20 20-30
Your Brain After Drugs
Normal
Alcohol Abuser
Alcoholic
3. Adolescence and the Brain
1. Developmental Issues 2. Brain Functioning
The Adolescent Brain is Still Developing
During adolescence, the brain is undergoing dramatic transformationsIn some brain regions, over 50 % of
neuronal connections are lost
Some new connections are formed
Net effect is pruning (a loss of neurons)
Adolescent Brain Changes
These brain changes are relevant to adolescent behaviorPrefrontal cortex (PFC) is
pruned; not fully developed until mid-20’s
Amygdala (and n.a.) show less pruning and tend to dominate the PFC
judgment
rewardsystem
amygdala nucleus
accumbens
prefrontalcortex
NOT GOOD NEWS!
planned thinking impulsiveness
self-control risk-taking
PFC
amygdala
“hot” decisions more likely than “cold” decisions
I like to use drugs
!!
PFC
amygdala
In the presence of stress…
I hate school; I am going to skip classes and get drunk
PFC
amygdala
GOOD NEWS!
The pruning of the PFC neurons produces a more efficient PFC by
young adulthoodI am
planning for the future
3. Adolescence and the Brain
4. Brain and Alcohol
1. Developmental Issues 2. Brain Functioning
Is addiction a brain disorder?
From “Oops” to Dependence
“Oops Phenomenon”
First use to “FEEL GOOD”
Some continue to compulsively use because of the reinforcing effects (e.g., to “FEEL NORMAL”)
Changes occur in the “reward system” that promote continued use
Reward System
The reward system is responsible for seeking natural rewards that have survival valueseeking food, water,
sex, and nurturingDopamine is this
system’s primary neurotransmitter
reward
Drugs Hijack the Brain’s Reward Circuitry
Continued use of alcohol reduces the brain’s dopamine production.
Because dopamine is part of the reward system, the brain is “fooled” that alcohol has survival value for the organism.
The reward system responds with “drug seeking behaviors”
Craving occurs and, eventually, dependence.
reward
‼
Evidence Animal Studies:
electrodes attached to “Reward Circuit” animals press lever to receive stimuli to brain they continue until collapse from exhaustion
Behavioral Genetics Studies: heredity plays a role
identical twins: > chance of becoming alcoholics than fraternal twins
adoptive children of alcoholics: > chance of becoming alcoholic;even true when raised by non-alcoholic parents
further research needed by gender
Human Studies: amygdala has memory of the drug after discontinuation.
Nature Video Alcohol Video
Front of Brain
Back of Brain
amygdalanot lit up
amygdalaactivated
3. Adolescence and the Brain
4. Brain and Alcohol
5. Youth, Brainand Alcohol
Are adolescents more susceptible toalcohol than adults?
1. Developmental Issues 2. Brain Functioning
Is addiction a brain disorder?
Are adolescents more susceptible to alcohol than adults?
Adult studies suggest that the areas of the adolescent brain that are remodeled are sensitive to the effects of alcohol
Difficult scientifically and ethically to study adolescent sensitivity to alcohol
amygdala
nucleusaccumbens
prefrontalcortex
Are adolescents more susceptible to alcohol than
adults?
Animal models can be easily used to explore this issue
Role of psychosocial factors can not be studied
Are adolescents more susceptible to alcohol than
adults?
1. Adolescent rats are less sensitive to effects of intoxication and less sensitive to the “hangover” that follows use
Are adolescents more susceptible to alcohol than
adults?
2. Adolescent rats are more sensitive to the social disinhibition induced by alcohol use
Wanna lookfor some cheese
with me?
Sure!
Are adolescents more susceptible to alcohol than adults?
3. Adolescent drunk rats perform worse on memory tasks than adult drunk rats
Ugh??
disrupts the hippocampus
brain damage in the PRF
converts informatio
n to memory
planned
thinking
Supporting Human Studies
1. Reduced sensitivity to intoxication
2. Increased sensitivity to social disinhibitions
3. Greater adverse effects to cognitive functioning
1. Reduced sensitivity to intoxication
3. Greater adverse effects to cognitive functioning
Survey Data Suggest that Adolescents Are More Sensitive to Alcohol
148
26 2430 32
0
20
40
60
80
100
8th Graders 10th Graders 12th Graders
5+ drinks in row, past 2 weeks
Been drunk past month
Monitoring the Future, 2001
Alcohol’s Effects
Adolescents with a history of extensive use….
Hippocampus (50%)
brain activity during memory tasks
brain activation when shown alcohol images
converts informati
on to memory
trigger for
relapse
(Brown, 2002; Wuethrich, 2001)
Are adolescents more susceptible to alcohol than
adults?
4. Hyperexcitability issue
Are adolescents more susceptible to alcohol than
adults?
4. Hyperexcitability issue
Alcohol relieves hyperexcitability state
Relief is temporary; continued seeking of alcohol is reinforced
Hyperexcitability is a key characteristic of conduct disorders, ADHD & other impulsive behaviors
Found in non-alcoholic relatives - suggests inheritance of brain wave patterns
ADHD
ODD
Con Dis
Sub Use Dis
Are adolescents more susceptible to alcohol than adults?
1 Reduced sensitivity to intoxication2 Increased sensitivity to social
disinhibitions3 Greater adverse effects to
cognitive functioning4 Medicates “excitability”
Most certainly YES
PFC
amygdala
“hot” decisions more likely than “cold”
decisions
I like to use drugs
!!
Less We Forget:The Adolescent Brain is Susceptible
Key Concepts
3. Adolescence and the Brain
4. Brain and Alcohol
5. Youth, Brainand Alcohol
Are adolescents more susceptible toalcohol than adults?
1. Developmental Issues 2. Brain Functioning
Is addiction a brain disorder?
6. Prevention & Treatment
Implications for Prevention and Treatment
PreventionThe earlier the betterEducate them about the
susceptibility of the adolescent brain and alcohol exposure
Skills training in the context of competing “voices” (PFC vs amygdala)
Marijuana: Trends in Perceived Availability, Perceived Risk, and Use for 12th Graders
0
20
40
60
80
100
1975 1977 1979 1981 1983 1985 1987 1989 1991 1993 1995 1997 1999 2001
Availability
Risk
Use
Per
cen
t
MTFS, 1975-2001
Availability= Fairly easy or very easy to getRisk = Great risk of harm in regular useUse= Once or more, past 30 days
Implications for TreatmentPsychosocial treatment
Verbal skills required in therapy may be compromised
Behavioral demands of self-control and relapse prevention may be compromised
Medications are being clinically tested to . . . Decrease anxiety and
depression associated with initial stages of recovery
Decrease desire to drinkTreat co-existing disordersNALTREXONE, ACAMPROSATE, SSRI’S
Is Addiction a Brain Disorder?Evidence to Support a “Yes”
When working with teenagers, remember…Adolescence is a time limited disorder
THANK [email protected]
extras
References Leshner A. Oops. How casual drug use leads to addiction.
National Institute on Drug Abuse web site: www.drugabuse.gov/Published_Articles/Oops.htmlSeptember, 2000.
National Institute on Alcohol Abuse and Alcoholism. Imaging and Alcoholism: A Window on the Brain. Alcohol Alert No. 47, April 2000.
National Institute on Alcohol Abuse and Alcoholism. Tenth Special Report to the U.S. Congress on Alcohol and Health, NIH Pub. No. 00-1583, 2000.
National Institute on drug Abuse. Principles of drug addiction treatment: A research-based guide. No. 99-4180, 1999.
From Discover vol. 22, No. 3, March 2001Meta analysis by Bernice Wuethrich
7 million youths between ages 12 and 20 binge drink at least once a month
Teen drinkers most susceptible to damage in the hippocampus and the prefrontal cortex
The hippocampus is 10% smaller in teens who use alcohol
Alcohol blocks long term potentiation in adolescent brain tissue; the production of glutamate which is responsible for memory formation
The impact on the developing brain continues through the early twenties
It is suspected that the physical impact of withdrawal – cell death and increase in number and sensitivity of hyperactive receptors – creates the brain damage.
Brown, 2002; Wuethrich, 2001
American Medical Association, 2002Sandra Brown, Ph.D.,
San Diego, Veterans Affairs Medical Center
Drinking at a young age can impair memory development and the ability to learn permanently
Research matched 56 adolescent drinkers with 56 non-drinkers
When given standardized test the drinkers scored worse in vocabulary, general information, memory and memory retrieval
Problems continued through years of follow-up