Insights from Neuroscience into the Effects of Impulsivity and Early Life Experience on School Readiness and Social Func

1. Insights from Neuroscienceinto the Effects of Impulsivity and Early Life Experience on School Readiness and Social Functioning in Youth Theodore P. Beauchaine, Ph.D. Robert Bolles & Yasuko Endo Associate Professor Associate Chair, Department of Psychology Child & Adolescent Adjustment Project

2. Learning Objectives • Recognize that impulsivity, the trait underlying most cases of ADHD, has well characterized genetic and brain bases. • Understand that ADHD is as ‘real’ as any psychiatric disorder. • Appreciate the role that environment plays in shaping impulsivity into more serious disruptive behaviors. • Be aware that impulsivity places children at risk for underachievement, school failure, and school dropout. • Recognize that impulsivity is not a trait that children ‘grow out of’. • Understand that the costs to individuals and society of ignoring the problem are enormous.

3. School Readiness • Set of skills, abilities, and other characteristics that foster successful transition into school(NICHD). • Self Regulation. • Sustained attention. • Inhibitory control over behavior. • Capacity to delay gratification. • Ability to suppress strong emotions. • Social and emotional competencies. • Emotion regulation. • Prosocial behavior and cooperation. • Basic understanding of emotions in self and others. • Absence of impulsivity, hyperactivity, and aggression.

4. Impulsivity Defined • Behavior that is swayed by emotional or involuntary impulses. • Behavior without adequate forethought. • Tendency to choose immediate over long-term rewards. • Engagement in behaviors that are likely to be punished. • Persistent reward-seeking behavior.

5. ALL young children are impulsive!

6. When is Impulsivity Problematic? • When it places a child at risk for injury. • When it interferes with social development. • When itimpedes skill acquisition and learning. • When it undermines the education and/or safety of other students. • When it contributes to school drop out. • When it eventuates in drug use, incarceration, and criminality.

7. When is Impulsivity Problematic? • Functional definitions (DSM-IV). • Some impairment from the symptoms is present in two or more settings (at school and at home). • There must be clear evidence of clinically significant impairment in social or academic functioning. • Statistical definitions (CBCL). 98% 2%

8. Impulsivity and ADHD • Impulsivity is highly heritable. About 80% of the variance in impulsivity is accounted for by genetic factors (e.g., Price et al., 2001). • Most impulsive children have at least one impulsive parent. • Heritable impulsivity is thecore trait underlying most cases hyperactive/impulsive ADHD(Barkley 1997). • Early ADHD predisposes to a host of negative outcomes: • Academic underachievement. • Social rejection. • Delinquency. • School drop out. • Alcohol and drug use. • Criminality.

9. Impulsivity Across the Lifespan: Why Early Identification is Important school conduct problems, suspensions drug use,criminality academic problems hyperactivity oppositionality& aggression disengagement& withdrawal delinquent peer group incarceration, recidivism age preschool middle-school adolescence

10. Delinquency • Pattern of repeated rule breaking behavior and criminality. • Disengagement from dominant cultural norms for achievement and behavior. • Easily bored and often irritable. • Frequent risky behavior despite high likelihood of punishment. • Delinquency often results in incarceration.

11. Growth in US Prison Population millions Source: Bureau of Justice Statistics

12. Current Incarceration Rates Citizens per 100,000 Source: Bureau of Justice Statistics

13. Disproportionality in Incarceration US Population, 2000 Prison Population, 2002

14. The Human Costs… • 20% of black males and 10% of Latinos serve prison time. • In some poor urban neighborhoods, 50% of black males will go to prison. • Once incarcerated, limited opportunities for upward mobility are all but eliminated. • Recidivism rates approach 60% over 5 years. • Early intervention is far more effective than incarceration when impulsive children are treated before delinquency emerges.

15. Current Intervention Approaches • Few impulsive or aggressive children receive any form of intervention. • When intervention is initiated, it is usually after ADHD has progressed to delinquency. • Those who are treated usually receive some form of group intervention. • Special education placements • Summer school, summer camps • Institutionalization • These interventions increase delinquency.

16. Group Interventions: Iatrogenic Effects treatment Teacher-reported Delinquency no treatment Source: Dishion et al., 1999

17. Intervention Effectiveness by Age 100 50 % Responders 0 Preschool Adolescence

18. The Ecology of Adolescent Behavior Treatment Provider Neighborhood School Peer Group Extended Parents Child Siblings Family

19. The High Costs of Incarceration • Delinquency is far and away the most costly mental health concern in the US. • Cost of incarcerating 1 person for 1 year: $23,205 • Cost of incarcerating 2 million per year: $48,000,000,000 • Many states are spending close to 20% of their annual budgets on corrections.

20. Interim Summary I • Impulsivity is among the most heritable of all behavioral traits. • Impulsivity interferes with school readiness and places children at risk for academic failure, social rejection, eventual drop out, and delinquency. • Environment plays an extremely important role in shaping impulsivity into serious conduct problems. • Impulsive children who grow up in high risk neighborhoods are at especially high risk for delinquency. • At-risk children need to be identified early in life in order to prevent the development of antisocial behavior.

21. Brain Bases of Impulsivity

22. Dopamine and Impulsivity • Almost all genes that have been linked with impulsive behavior affect dopamine (DA) neurotransmission. • DAT1 gene • DRD2 gene • DRD4 gene • MAO-A gene • COMT gene • 5HTT gene • Genes do not code for specific behaviors. Rather, they affect brain functioning, which contributes to broad behavioral traits, such as impulsivity.

23. Dopamine and Reward nucleus accumbens ventral tegmental area The Mesolimbic DA System

24. Mesolimbic Dopamine Activity phasic response tonic activity tonic activity neural firing time reward cue satiation

25. The Mesolimbic DA System • Implicated in all motivated (rewarding) behaviors. • Tonic levels associated with mood states. • High tonic DA activity → positive affectivity (Ashby et al., 1999). • Low tonic DA activity → negative affectivity, irritability (Laakso et al., 2003). • Activity of the system is experience dependent. • Repeated phasic activation leads to reduced tonic activation and sensitization.

26. Mesolimbic Dopamine Activity sensitizedphasicactivity original responsepattern reducedtonicactivity time reward cue satiation

27. Experience Dependence • Rewarding behaviors that strongly increase phasicmesolimbic dopamine activity: • Smoking • Alcohol use • Illicit drug use • Methamphetamine • Cocaine • Opiates • Gambling • Video games • These activities down-regulate tonic DA activity.

28. Effects of Chronic DA Activation normal control alcoholdependent normal control cocainedependent

29. Dopamine and Impulsivity • Children with ADHD exhibit low tonic and lowphasic mesolimbic activity (e.g., Sagvolden et al., 2005). • This is a likely neurobiological substrate of negative affectivity (Beauchaine et al., 2001). • Low mesolimbic activity is highly heritable, predisposing to impulsivity and delinquency. • Environmental risks during development exacerbate this effect(e.g., Poeggel et al., 1999). • Exposure to smoking • Child abuse and neglect • Drug use

30. phasic response tonic activity normal ADHD ADHD +high stressenvironment reward cue

31. Assessing Reward Sensitivity • Incentive-motivation (reward) tasks. Simple computer games in which children • make money for correct responses during reward trials, and • make no money for correct responses during extinction trials.

32. Task: Fixation +

33. Task: Reward $3.20

34. Task: Reward $3.60

35. Task: Non-Reward $0.00

36. Striatal Activity: Reward Source: Knutson et al., 2001

37. Striatal Activity: Reward Control ADHD Source: Scheres et al., 2007

38. Implications I: Learning • Mesolimbic DA responding integral to associative learning (Sagvolden, 2005). • Phasic DA response signals to other areas of brain that an event is important, and that learning should take place.

39. normal normal associative learning gradient ADHD ADHD associative learning gradient Reinforcer(e.g., praise, intrinsic reward value, etc.)

40. Implications I: Learning • Mesolimbic DA involved integrally in associative learning (Sagvolden, 2005). • Phasic DA response initiates signal to other areas of brain that an event is important, and that learning should take place. • Impulsive children often require more trials to learn from external events.

41. Implications II: Reward Seeking • Children low in tonic DA activity experience high levels of negative affect and irritability. • This leads to impulsive reward-seeking behavior to up-regulate chronically aversive mood. • Low phasic DA activity means less pleasure from reward-seeking behavior. • This elicits more reward-seeking and predisposes to delinquency. • Children in high risk neighborhoods are particularly susceptible.

42. Impulsivity & Neighborhood Risk Number of Delinquent Acts Source: Lynam et al., 2000

43. Impulsivity & Neighborhood Risk Violent Delinquency Source: Lynam et al., 2000

44. Interim Summary II • Impulsivity is highly heritable (about 80%). • At the neural level, heritable impulsivity is expressed as deficient DA responding. • Low DA gives rise to negative affectivity and irritability. • These aversive mood states lead to reward-seeking behavior in efforts to ‘self-stimulate’. • Environmental risks reinforce brain-based vulnerabilities, leading to more serious behavior problems: • ADHD. • Conduct problems. • Alcohol and drug use. • Criminality.

45. Dopamine & Extinction (Non-Reward) anterior cingulate cortex nucleus accumbens ventral tegmental area The Mesolimbic DA System

46. The Anterior Cingulate Cortex • Mid-brain structure with complex functions: • Allocation of attention to important yet unanticipated events. • Coordination of thought and emotion. • Error detection. • Error monitoring. • Extinction learning.

47. ACC Activity: Reward vs. Extinction Reward Extinction Control ADHD Source: Gatzke-Kopp, Beauchaine et al., 2007

48. Deficient ACC Activity:Implications for Learning • Deficient ACC activity during extinction (non-reward) likely gives rise to: • Problems unlearning previously rewarded behaviors. • Response perseveration. • Poor monitoring of one’s own mistakes.

49. Summary • Impulsivity is highly heritable and confers risk for poor school readiness and problems with self regulation. • Examining neural processes of impulsive children suggests deficiencies in both a. Associative learning of new information, and b. Extinction (unlearning) of no longer useful old information. • The same neural deficiencies that affect learning also predispose to negative affectivity, irritability, and low motivation. • These neural deficiencies can be detected inpreschool, and confer risk for later delinquency(Crowell, Beauchaine et al., 2005). • Early intervention is essential because a. Neural vulnerabilities are amplified by environmental risk. b. Interventions become increasingly ineffective in older children.

50. What do Effective Interventions Look Like? • Parent training for effective behavior management at home. Source: Beauchaine, Webster-Stratton, & Reid, 2005.