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Alcohol and the Adolescent Brain Ken Winters, Ph.D. Department of Psychiatry University of Minnesota [email protected] U.S.E.D. Grants to Reduce Alcohol Abuse Conference November 18, 2003 Our ex-Governor was a professional wrestler Staff are all above average. Women are strong. Men are good looking. U of Minnesota, Center for Adolescent Substance Abuse Research 1. Developmental Issues 6. Prevention and Treatment 2. Brain Functioning 3. Adolescence and the Brain 5. Youth, Brain and Alcohol 4. Brain and Alcohol Are adolescents more susceptible to alcohol than adults? Is addiction a brain disorder? 1. Developmental Issues Alcohol Use by Youth Youth alcohol use occurs on a continuum Most youth have used some alcohol 7 million teens binge drink at least once a month Alcohol Use Trends in prevalence of drugs for 12th graders: 1994 to 2001 Year 30-Day 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 Use Disorders (AUDs) are Relatively Rare AUD rates vary; 3-10% Most youth who use do not meet criteria for abuse or dependence Alcohol Problems 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 Year 1994 Daily Cigarettes % 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 100 80 60 Availability Risk Use 40 20 0 1975 1977 1979 1981 1983 1985 1987 1989 1991 1993 1995 1997 Availability= Fairly easy or very easy to get Risk = Great risk of harm in regular use Use= Once or more, past 30 days 1999 2001 MTFS, 1975-2001 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 Many predate onset of AUD ADHD > comorbidity, >AUD Oppositional Defiance Disorder Depression Alcohol Use Disorder Conduct Disorder Gambling Relapse > if comorbidity Anxiety Medication may be appropriate Developmental Phases of Adolescence • Individuation • need to develop personal identity • Separation • need to separate from parents These forces can disrupt our prevention and treatment efforts Stages of Change Prochaska and DiClimente Maintenance Action Action Preparation Relapse Pre-contem. Precontemplation Contemplation Stages of Change for Most Youth? Contemplation Prep Pre-contem. 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 explosion MRI PET CAT These brain imaging techniques produce windows to observe the effects of substances on the brain Imaging Modalities CT Anatomic MRI SPECT MR Spectroscopy FDG PET Ligand PET 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 1. Developmental Issues 2. Brain Functioning 3. Adolescence and the Brain The Adolescent Brain is Still Developing During adolescence, the brain is undergoing dramatic transformations In 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 behavior Prefrontal cortex (PFC) is pruned; not fully developed until mid-20’s Amygdala (and n.a.) show less pruning and tend to dominate the PFC prefrontal cortex amygdala nucleus accumbens judgment reward system I like to use drugs! ! PFC amygdala NOT decisions GOOD NEWS! “hot” more likely than “cold” planned thinking decisions impulsiveness self-control risk-taking In the presence of stress… PFC I hate school; I am going to skip classes and get drunk amygdala GOOD NEWS! The pruning of the PFC neurons produces a more efficient PFC by young adulthood I am planning for the future amygdala PFC 1. Developmental Issues 2. Brain Functioning 3. Adolescence and the Brain 4. Brain and Alcohol 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 value seeking food, water, sex, and nurturing Dopamine 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. amygdala not lit up Front of Brain amygdala activated Back of Brain Nature Video Alcohol Video 1. Developmental Issues 2. Brain Functioning 3. Adolescence and the Brain 5. Youth, Brain and Alcohol 4. Brain and Alcohol Are adolescents more susceptible to alcohol than adults? 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 prefrontal cortex amygdala nucleus accumbens Difficult scientifically and ethically to study adolescent sensitivity to alcohol 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 look for 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 converts information to memory Ugh? ? disrupts the hippocampus brain damage in the PRF planne d thinkin g Supporting Human Studies 1. Reduced Reduced sensitivity sensitivity to to 1. intoxication intoxication 2. Increased sensitivity to social disinhibitions 3. Greater adverse effects 3. Greater adverse effects to cognitive cognitive functioning functioning to Survey Data Suggest that Adolescents Are More Sensitive to Alcohol Monitoring the Future, 2001 100 80 5+ drinks in row, past 2 weeks 60 Been drunk past month 40 26 20 0 14 24 30 32 8 8th Graders 10th Graders 12th Graders Alcohol’s Effects (Brown, 2002; Wuethrich, 2001) Adolescents with a history of extensive use…. converts informatio n to memory Hippocampus (50%) brain activity during memory tasks brain activation when shown alcohol images trigger for relapse 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 Sub Use Dis ODD Con Dis Are adolescents more susceptible to alcohol than adults? Most certainly YES 1 Reduced sensitivity to intoxication 2 Increased sensitivity to social disinhibitions 3 Greater adverse effects to cognitive functioning 4 Medicates “excitability” Less We Forget: The Adolescent Brain is Susceptible I like to use drugs! ! PFC amygdala “hot” decisions more likely than “cold” decisions 1. Developmental Issues 6. Prevention & Treatment 5. Youth, Brain and Alcohol Key Concepts 2. Brain Functioning 3. Adolescence and the Brain 4. Brain and Alcohol Are adolescents more susceptible to alcohol than adults? Is addiction a brain disorder? Implications for Prevention and Treatment Prevention The earlier the better Educate 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 100 80 60 Availability Risk Use 40 20 0 1975 1977 1979 1981 1983 1985 1987 1989 1991 1993 1995 1997 Availability= Fairly easy or very easy to get Risk = Great risk of harm in regular use Use= Once or more, past 30 days 1999 2001 MTFS, 1975-2001 Implications for Treatment Psychosocial treatment Verbal skills required in therapy may be compromised Behavioral demands of selfcontrol 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 drink Treat co-existing disorders NALTREXONE, ACAMPROSATE, SSRI’S Is Evidence Addiction to aSupport Brain Disorder? a “Yes” Adolescence is a time limitedremember… disorder When working with teenagers, THANK YOU! [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.html September, 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. 001583, 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 2001 Meta 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, 2002 Sandra 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