Insights from Neuroscience into 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

Learning Objectives1. Recognize that impulsivity, the trait underlying most cases of

ADHD, has well characterized genetic and brain bases.

2. Understand that ADHD is as ‘real’ as any psychiatric disorder.

3. Appreciate the role that environment plays in shaping impulsivity into more serious disruptive behaviors.

4. Be aware that impulsivity places children at risk for underachievement, school failure, and school dropout.

5. Recognize that impulsivity is not a trait that children ‘grow out of’.

6. Understand that the costs to individuals and society of ignoring the problem are enormous.

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.

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.

ALL young children are impulsive!

When is Impulsivity Problematic?

When it places a child at risk for injury.

When it interferes with social development.

When it impedes 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.

When is Impulsivity Problematic?

Functional definitions (DSM-IV).

C. Some impairment from the symptoms is present in two or more settings (at school and at home).

D. There must be clear evidence of clinically significant impairment in social or academic functioning.

Statistical definitions (CBCL).

98% 2%

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 the core 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.

Impulsivity Across the Lifespan: Why Early Identification is Important

agepreschool

hyperactivity

oppositionality& aggression

school conduct problems, suspensions

middle-school

disengagement& withdrawal

academic problems

adolescence

delinquent peer group

drug use,criminality

incarceration, recidivism

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.

Growth in US Prison Population

0.0

0.5

1.0

1.5

2.0

1930 1940 1950 1960 1970 1980 1990 2000 2005

m

illio

ns

Source: Bureau of Justice Statistics

Current Incarceration Rates

0 100 200 300 400 500 600 700 800

US

England

Spain

Canada

Australia

Italy

Netherlands

Germany

France

Sweden

Switzerland

J apan

Citizens per 100,000

Source: Bureau of Justice Statistics

Disproportionality in Incarceration

Black12.32%

White69.13%

Latino12.55%

Other6.00%

US Population, 2000

Black43.91%

Latino18.26%

Other3.11%

White34.72%

Prison Population, 2002

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.

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.

Group Interventions: Iatrogenic Effects

1

2

3

4

5

Pre-treatment Post-treatment

1 year 2 years 3 years

Tea

cher

-rep

orte

d D

elin

quen

cy

treatment

no treatment

Source: Dishion et al., 1999

Intervention Effectiveness by Age

% R

espo

nder

s

100

50

0 Preschool Adolescence

The Ecology of Adolescent Behavior

Child

Parents

Siblings

Extended

Peer Group

Family

School

Neighborhood

Treatment Provider

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.

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.

Brain Bases of Impulsivity

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.

Dopamine and Reward

The Mesolimbic DA System

ventral tegmental area

nucleus accumbens

Mesolimbic Dopamine Activity

tonic activity

reward cue

phasic response

tonic activity

satiation

time

neural firing

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.

Mesolimbic Dopamine Activity

reward cue satiation

time

original responsepatternreducedtonicactivity

sensitizedphasicactivity

Experience Dependence

Rewarding behaviors that strongly increase phasic mesolimbic dopamine activity:

Smoking Alcohol use

Illicit drug use Methamphetamine Cocaine Opiates

Gambling Video games

These activities down-regulate tonic DA activity.

Effects of Chronic DA Activation

normal control

alcoholdependent

normal control

cocainedependent

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

normalADHDADHD +high stressenvironment

reward cue

tonic activity

phasic response

Assessing Reward Sensitivity

Incentive-motivation (reward) tasks. Simple computer games in which children

a) make money for correct responses during reward trials, and

b) make no money for correct responses during extinction trials.

Task: Fixation

+

Task: Reward

$3.20

Task: Reward

$3.60

Task: Non-Reward

$0.00

Striatal Activity: Reward

Source: Knutson et al., 2001

Striatal Activity: Reward

Source: Scheres et al., 2007

Control ADHD

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.

normal

ADHD

Reinforcer(e.g., praise, intrinsic reward value, etc.)

normal associative learning gradient

ADHD associative learning gradient

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.

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.

Impulsivity & Neighborhood Risk

0

2

4

6

8

10

High SES MiddleSES

Low SES PublicHousing

Non-impulsiveImpulsive

Num

ber

of D

elin

quen

t A

cts

Source: Lynam et al., 2000

Impulsivity & Neighborhood Risk

0

1

2

3

High SES MiddleSES

Low SES PublicHousing

Non-impulsiveImpulsive

Vio

lent

Del

inqu

ency

Source: Lynam et al., 2000

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.

Dopamine & Extinction (Non-Reward)

The Mesolimbic DA System

ventral tegmental area

nucleus accumbens

anterior cingulate cortex

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.

ACC Activity: Reward vs. Extinction

Control

Reward

ADHD

Extinction

Source: Gatzke-Kopp, Beauchaine et al., 2007

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.

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, andb. 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 in preschool, 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.

What do Effective Interventions Look Like?

Parent training for effective behavior management at home.

Source: Beauchaine, Webster-Stratton, & Reid, 2005.

Parenting & Progression of Impulsivity

Hyperactivity

ParentReport

Teacher Report

Conduct Problems

PeerNominatio

n

Interviewer

ImpressionObserved

Behavior

.54

CoerciveParental Discipline

Observed

Nattering

Harsh Disciplin

e

Observer Impressio

n

.59 .77

.06

Source: Patterson et al., 2000

What do Effective Interventions Look Like?

Parent training for effective behavior management at home.

Teacher training for effective behavior management in the classroom.

Child training of effective strategies for managing trait impulsivity.

Source: Beauchaine, Webster-Stratton, & Reid, 2005.

Preventing and Treating Behavior Problems in Young Children: A Parent-Teacher-School Partnership

Carolyn Webster-Stratton, Ph.D. University of Washington Department of Family and Child Nursing

Tomorrow, 3:30-5 p.m.

What do Effective Interventions Look Like?

The Prefrontal Cortex

The Mesocortical DA System

ventral tegmental area

nucleus accumbens

anterior cingulate cortex

pre-frontal cortex

The Prefrontal Cortex

The Prefrontal Cortex Responsible for ‘executive functions’:

Long term planning Inhibitory control over behavior Overriding strong emotions

Complex reasoning and thought processes.

Among the last brain areas to develop fully.

Coordinates with mesolimbic structures to regulate behavior.

PFC neurodevelopment is compromised by both mesolimbic deficiencies and adverse environmental experiences (e.g., Poeggel et al., 1999).

Gray Matter Development

Source: Gogtay et al., 2004

Acknowledgements

National Institute of Mental Health

University of Washington Royalty Research Fund

Sharon Brenner Hilary MeadJane Chipman-Chacon Kate ShannonSheila Crowell Jamila ReidLisa Gatzke-Kopp Patrick SylversEmily Neuhaus Carolyn Webster-

StrattonPenny Marsh

Numerous UW undergraduate RAs

A Similar Talk Can be Viewed on University of Washington TV:

Brain Science as a Means of Understanding Delinquency in Youth

http://www.uwtv.org/programs/displayevent.asp?rid=3402

Cardiac Responses to Reward

Sympathetic nervous system (SNS)-linked cardiac activity may serve as a proxy for central DA activity:

Heart rate acceleration facilitates approach behaviors.

Approach-related behaviors requires energy mobilization, a function served by the SNS.

Increases in cardiac output are facilitated by SNS-mediated changes in contractile force of the left ventricle.

DA infusions into mesolimbic structures induce SNS-mediated increases in cardiac output (van den Buuse et al., 1998).

Assessing SNS-Linked Cardiac Activity

Pre-ejection period

Tonic PEP and Delinquency

98

96

94

92

90

88

86

1 2 3 4 5 6 7

Adolescents

Non-delinquent

Delinquent

1 2

Preschoolers

Non-ADHD

ADHD

90

86

82

78

74

70

68

Phasic PEP During Reward

ConductProblems

No conductproblems

Delinquent

adolescence

middle school

preschool

ADHD

NoADHD

Non-delinquent