The Psychobiological basis of antisocial behaviour
There are biological links, and we can use them to predict childhood aggression.
Genetic influences are there, but always will be polygenetic (many genes responsible for one behaviour or characteristic).
MAOA moderates effect of maltreatment (see paper)
Another paper looks at psychopathology of mother (second slide)
A lot of teenagers get involved in anti-social behaviour, very common. What proportion commits violent behaviour though?
– In one study, biggest indicator of violence was depression of mother in pregnancy (as opposed to depression at other stages of childhood)
– Comparing mothers past history of smoking, drinking, anxiety and conduct disorder; conduct disorder (CD) was biggest indicator of violence.
FACTS (Lynam, PB, 1996)
1) Persistence of AB – to find tomorrow’s antisocial adult you must look at todays antisocial children.
2) Children with severe conduct problems become antisocial adults 4—70% of the time.
What are the developmental correlates of the chronic offender?
Terminology and Perspectives
– Mental Disorder: CD, ODD, DBD, ASPD
– Criminal perspective: violence and criminality
– Psychopathy (psychiatry): condition characterized by lack of empathy, conscience, poor impulse control and/or manipulative behaviours.
We don’t give children this label. We can measure high/low Psychopathic traits.
ADHD is NOT a risk factor, only is if its comorbid with one of the above mental disorders.
What Turns Children to Violence?
Example of two brothers on two boys in Edlington. Attackers exposed to a lot of violence. Makes kids far more likely to engage in anti-social behaviour; situations where they are no longer the victim.
CD is complicated group of behavioural and emotional problems in youngsters. Can’t follow rules, behave in a antisocial way; often viewed as ‘bad’ but not ‘mentally ill’.
– Cruelty to others
– Rule breaking
– Bullying, fighting
Prevalence is 5-7%.
Highly costly to society (at least ten times more than well developing children) because of personal costs, own health, educational failure, vandalism, problems at home and work.
Many interventions are ineffective, have bad effects. Early prevention strategies are called for.
– Parent training management: based on social behavioural learning theory. Works in least serious cases.
– Anger management: Social skills training and problem solving, targeting specific areas child has problems with. Works in not so serious cases, seems to reduce effectiveness over time.
– Multi-systemic treatment: parent training, family therapy, anger management, social skills training, treatment, etc etc.
Works better but still ineffective for many.
CD children are not ‘simply’ a product of a bad environment. Changing environment doesn’t always improve condition.
Some kids with CD are inherently difficult children.
Taxonomy of ASB – Moffit 1993 , uber citations
(some evidence that model might not be the best thing since sliced bread)
– Different prognosis for ASB depending on age of onset.
If it starts in childhood, probably on life-course trajectory
From ten years old, limited trajectory
Basically, the later it starts the earlier the trajectory stops.
No gender differences.
It’s neurobiologically based.
Moffit says that the ‘Maturity Gap’ causes a lot of kids between around 14 and 18 to be anti-social (are adults physically but are still treated like kids).
Do aggressive children share similar deficit with antisocial adults?
Emotional deficits: fearlessness, no empathy, psychophysiological under-arousal (heart rate skin conductance, startle reflex, EEG)
Cognitive (prefrontal lobe) deficits: Executive functions, **
Why is ASB related to decreased ANS arousal?
1) Sensation Seeking Theory – High need for risky or adventurous activities, boredom. High sensation seekers have low ANS resting levels (Zuckerman)
2) Fearlessness – Physiological under-activity, punishment insensitivity, poor social conditioning & socialization. Low ANS reactivity to events.
Do antisocial people have lower ANS levels?
Do more serious offenders have lower ANS levels than less serious offenders?
Is low HR a biological marker for aggression?
Raine et al 1997 – Sample = 1795 3-year-olds
Resting HR was assessed for 1 minute.
Aggressive behaviour assessed via CBCL in 1130 children at age 11:
– Subgroups created based on 1 SD above/below mean
– High-aggression (n=171) vs. low-aggression (n=224)
– H-HR (n(=185) vs. L-HR (n=177)
Children who were very aggressive at age 11, had significantly lower resting heart-rates when they were 3.
Kids with low HR at age 3 were more aggressive at age 11
Kids who were aggressive at age 11 had lower HR at age 3
Do results support the fearlessness or sensation seeking theory?
Raine et al 1990 – sample 101 15 year old school boys.
– Measures: resting HR, SC (nonspecific SC fluctuations, i.e. NSF – neurotic, anxious; would expect low level if fearless) reported
– Outcome: computer search at criminal record office for those ‘guilty and sentenced’ at age 24 (n=17).
Results: Criminals to be significantly lower HR and NSF at age 15.
77% of non-criminals and 65% of criminals were correctly classified as criminal or non-criminal based on the psychophysiological variables alone
23% false positive
35% false negative
Can high arousal be a protective factor?
Raine et al 1995
Same sample as before but now aged 29, same computer search
Three groups: 17 antisocial adult =desisters, 17 teenage antisocial adult =persisters, and 17 non-antisocial =controls.
HR and NSF measured.
SC paradigm gives startle and see how many it takes until habituation happens.
Desistors have even higher levels of HR than controls,
Boys who desisted from adult crime had higher ANS values than those who persisted; may indicate better information processing and attention.
ISSUE: could biofeedback training help reduce ASB?
Emotional responses to emotional stimuli
Using picture stimuli to evoke change in mood, feeling and emotion.
Normally: high arousal at negative, normal at neutral, low arousal at positive,
Startle reflex (close eyes at a flash) strength measure with electrodes on face, anxiety and emotion modulation.
Dysfunctions in the amygdala give rise to reduced augmentation of the startle reflex by visual primes.
The startle reflex is modulated by affective (emotional) content.
In psychopaths, neutral gives highest response, and negative images gives lower than neutral.
Van Goozen et al 2004
Mean blink magnitutes for startles presented during slides in children.
CD group vs normal control group. CD****
Childhood Psychopathy Study by Blair (1999)
Psychopathy is NOT diagnosed in children or adolescents
Psychopathic tendencies can sometimes be recognized in childhood or early teens, and is recognized are diagnosed as Conduct Disorder.
These kids often appear callous, unemotional, and immune to punishment, nothing seems to modify their undesirable behaviour,
Is it a deficit of fear?
Is it dysfunction of response to distress?
Specialised school with behavioural and emotional problems.
16 kids with high PSD EBD, 16 with low, 16 NC kids,
SCL baseline, SCRs in response to threatening, distressing and neutral IAPS slides.
Psychopathic kids have lower SCL and SCR than both other groups.
Also show low levels of response to threat and distress on IAPS slides.
Concludes that it’s particular problem to distress because that was sig difference, but threat was not sig different from controls.
Van Goozen 2000
– 26 DBD children and 26 age and sex matched NC children
– Psychosocial stressor: frustration, provocation, during competition
– HR and SC were recorded continuously and moods were recorded at intervals.
Works extremely well with aggressive kids.
Negative Moods during stress:
Pre – High negative, unsure about situation
Stress – Extremely high in CD, stays same high in NC,
Post – NC goes right down, CD don’t recover, level still more negative than pre.
BUT HR and SCL are ALWAYS lower than controls throughout the entire study, even though the CD’s are so intensly emotional and angry.