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Alcohol and the Adolescent Brain

Alcohol and the Adolescent Brain. Ken Winters, Ph.D. Department of Psychiatry University of Minnesota winte001@umn.edu U.S.E.D. Grants to Reduce Alcohol Abuse Conference November 18, 2003. Staff are all above average. Women are strong. Men are good looking. Our ex-Governor was

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Alcohol and the Adolescent Brain

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  1. Alcohol and the Adolescent Brain Ken Winters, Ph.D. Department of Psychiatry University of Minnesota winte001@umn.edu U.S.E.D. Grants to Reduce Alcohol Abuse Conference November 18, 2003

  2. Staff are all above average. Women are strong. Men are good looking. Our ex-Governor was a professional wrestler U of Minnesota, Center for Adolescent Substance Abuse Research

  3. 1. Developmental Issues 2. Brain Functioning 6. Prevention and Treatment 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?

  4. 1. Developmental Issues

  5. 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

  6. Trends in prevalence of drugs for 12th graders: 1994 to 2001 30-Day YearAlcohol % 199450.1 1995 51.3 1996 50.8 1997 52.7 1998 52.0 1999 51.0 2000 50.0 2001 49.8 MTFS, 1975-2001

  7. Alcohol Use Disorders (AUDs)are Relatively Rare AUD rates vary; 3-10% Alcohol Problems Most youth who use do not meet criteria for abuse or dependence boy AUD rates > girl AUD rates

  8. 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

  9. Trends in prevalence of drugs for 12th graders: 1994 to 2001 Daily YearCigarettes % 199419.4 199521.7 199622.2 199724.5 199822.5 199923.1 200020.5 200119.0 MTFS, 1975-2001

  10. Marijuana: Trends in Perceived Availability, Perceived Risk, and Use for 12th Graders Percent Availability= Fairly easy or very easy to get Risk = Great risk of harm in regular use Use= Once or more, past 30 days MTFS, 1975-2001

  11. 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.

  12. Comorbid Disorders with AUD > comorbidity, >AUD Many predate onset of AUD ADHD Oppositional Defiance Disorder Depression Alcohol Use Disorder Conduct Disorder Gambling Anxiety Relapse > if comorbidity Medication may be appropriate

  13. 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

  14. Stages of ChangeProchaska and DiClimente Action Precontemplation

  15. Stages of Change for Most Youth? Precontemplation

  16. Working with parents

  17. 1. Developmental Issues 2. Brain Functioning

  18. 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

  19. 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

  20. 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

  21. “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

  22. CT SPECT FDG PET Ligand PET Anatomic MRI MR Spectroscopy fMRI Diffusion MRI Imaging Modalities

  23. Your Brain on Alcohol 1-2 Min 3-4 5-6 6-7 7-8 8-9 9-10 10-20 20-30

  24. Your Brain After Drugs Normal Alcohol Abuser Alcoholic

  25. 1. Developmental Issues 2. Brain Functioning 3. Adolescence and the Brain

  26. 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)

  27. Adolescent Brain Changes prefrontal cortex • 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 amygdala nucleus accumbens judgment reward system

  28. I like to use drugs!! PFC NOT GOOD NEWS!  planned thinking impulsiveness  self-control  risk-taking amygdala “hot” decisions more likely than “cold” decisions

  29. In the presence of stress… I hate school; I am going to skip classes and get drunk PFC amygdala

  30. GOOD NEWS! The pruning of the PFC neurons produces a more efficient PFC by young adulthood I am planning for the future amygdala PFC

  31. 1. Developmental Issues 2. Brain Functioning 3. Adolescence and the Brain 4. Brain and Alcohol Is addiction a brain disorder?

  32. From “Oops” to Dependence

  33. “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

  34. 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

  35. ‼ 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

  36. 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

  37. Human Studies: amygdala has memory of the drug after discontinuation. amygdalanot lit up amygdalaactivated Front of Brain Back of Brain Nature Video Alcohol Video

  38. 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?

  39. 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

  40. 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

  41. Are adolescents more susceptible to alcohol than adults? • Adolescent rats are less sensitive to effects of intoxication and less sensitive to the “hangover” that follows use

  42. Are adolescents more susceptible to alcohol than adults? • Adolescent rats are more sensitive to the social disinhibition induced by alcohol use Sure! Wanna look for some cheese with me?

  43. Are adolescents more susceptible to alcohol than adults? • 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 planned thinking

  44. 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

  45. Survey Data Suggest that Adolescents Are More Sensitive to Alcohol Monitoring the Future, 2001

  46. Alcohol’s Effects (Brown, 2002; Wuethrich, 2001) • Adolescents with a history of extensive use…. Hippocampus (50%) brain activity during memory tasks brain activation when shown alcohol images converts information to memory trigger for relapse

  47. Are adolescents more susceptible to alcohol than adults? • Hyperexcitability issue

  48. 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 Sub Use Dis Con Dis

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