Title: Insights from Neuroscience into the Effects of Impulsivity and Early Life Experience on School Readi
1Insights 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
2Learning 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.
3School 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.
4Impulsivity 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.
5ALL young children are impulsive!
6When 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.
7When 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
8Impulsivity 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.
9Impulsivity 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
10Delinquency
- 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.
11Growth in US Prison Population
millions
Source Bureau of Justice Statistics
12Current Incarceration Rates
Citizens per 100,000
Source Bureau of Justice Statistics
13Disproportionality in Incarceration
US Population, 2000
Prison Population, 2002
14The 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.
15Current 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.
16Group Interventions Iatrogenic Effects
treatment
Teacher-reported Delinquency
no treatment
Source Dishion et al., 1999
17Intervention Effectiveness by Age
100
50
Responders
0
Preschool
Adolescence
18The Ecology of Adolescent Behavior
Treatment Provider
Neighborhood
School
Peer Group
Extended
Parents
Child
Siblings
Family
19The 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.
20Interim 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.
21Brain Bases of Impulsivity
22Dopamine 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.
23Dopamine and Reward
nucleus accumbens
ventral tegmental area
The Mesolimbic DA System
24Mesolimbic Dopamine Activity
phasic response
tonic activity
tonic activity
neural firing
time
reward cue
satiation
25The 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.
26Mesolimbic Dopamine Activity
sensitizedphasicactivity
original responsepattern
reducedtonicactivity
time
reward cue
satiation
27Experience 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.
28Effects of Chronic DA Activation
normal control
alcoholdependent
normal control
cocainedependent
29Dopamine 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
30phasic response
tonic activity
normal
ADHD
ADHD high stressenvironment
reward cue
31Assessing 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.
32Task Fixation
33Task Reward
3.20
34Task Reward
3.60
35Task Non-Reward
0.00
36Striatal Activity Reward
Source Knutson et al., 2001
37Striatal Activity Reward
Control
ADHD
Source Scheres et al., 2007
38Implications 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.
39normal
normal associative learning gradient
ADHD
ADHD associative learning gradient
Reinforcer(e.g., praise, intrinsic
reward value, etc.)
40Implications 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.
41Implications 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.
42Impulsivity Neighborhood Risk
Number of Delinquent Acts
Source Lynam et al., 2000
43Impulsivity Neighborhood Risk
Violent Delinquency
Source Lynam et al., 2000
44Interim 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.
45Dopamine Extinction (Non-Reward)
anterior cingulate cortex
nucleus accumbens
ventral tegmental area
The Mesolimbic DA System
46The 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.
47ACC Activity Reward vs. Extinction
Reward
Extinction
Control
ADHD
Source Gatzke-Kopp, Beauchaine et al., 2007
48Deficient ACC ActivityImplications for Learning
- Deficient ACC activity during extinction
(non-reward) likely gives rise to - Problems unlearning previously rewarded
behaviors. - Response perseveration.
- Poor monitoring of ones own mistakes.
49Summary
- 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 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.
50What do Effective Interventions Look Like?
- Parent training for effective behavior management
at home.
Source Beauchaine, Webster-Stratton, Reid,
2005.
51Parenting Progression of Impulsivity
PeerNomination
ParentReport
.54
.06
Conduct Problems
InterviewerImpression
Hyperactivity
Teacher Report
Observed Behavior
.77
.59
CoerciveParental Discipline
Observed Nattering
Harsh Discipline
Observer Impression
Source Patterson et al., 2000
52What 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.
53What do Effective Interventions Look Like?
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, 330-5 p.m.
54The Prefrontal Cortex
anterior cingulate cortex
pre-frontal cortex
nucleus accumbens
ventral tegmental area
The Mesocortical DA System
55The Prefrontal Cortex
56The 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).
57Gray Matter Development
Source Gogtay et al., 2004
58Acknowledgements
National Institute of Mental Health University
of Washington Royalty Research Fund Sharon
Brenner Hilary Mead Jane Chipman-Chacon
Kate Shannon Sheila Crowell Jamila Reid Lisa
Gatzke-Kopp Patrick Sylvers Emily Neuhaus
Carolyn Webster-Stratton Penny Marsh
Numerous UW undergraduate RAs
59A 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?ri
d3402
60(No Transcript)
61Cardiac 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).
62Assessing SNS-Linked Cardiac Activity
Pre-ejection period
63Tonic PEP and Delinquency
98 96 94 92 90 88 86
90 86 82 78 74 70 68
Delinquent
ADHD
Non-delinquent
Non-ADHD
1 2 3 4 5 6 7
Adolescents
1 2 Preschoolers
64Phasic PEP During Reward
adolescence
middle school
preschool
No conductproblems
Non-delinquent
NoADHD
ConductProblems
ADHD
Delinquent