Relationships Between Relationships Between Central and Autonomic Central and Autonomic

Measures of Arousal at Age Measures of Arousal at Age 15 Years and Criminality at 15 Years and Criminality at

Age 24 YearsAge 24 Years

Raine, Venables, and WilliamsRaine, Venables, and Williams

Presented by Jamie RenspePresented by Jamie RenspeJune 25, 2007June 25, 2007

Prior ResearchPrior Research Criminality is in part genetically determinedCriminality is in part genetically determined

Adoption studiesAdoption studies Bohman et al.Bohman et al.

Found increased rates of criminality in biological parents of Found increased rates of criminality in biological parents of petty criminalspetty criminals

Mednick et al.Mednick et al. Do criminal records for a biological parent increase the Do criminal records for a biological parent increase the

likelihood of crime in his or her adopted-away offspring?likelihood of crime in his or her adopted-away offspring? Biological parents convictedBiological parents convicted→20% sons convicted→20% sons convicted Biological and adoptive parents convicted→24.5% sons convictedBiological and adoptive parents convicted→24.5% sons convicted

So it is not just genetics, but also the environmentSo it is not just genetics, but also the environment InteractionInteraction

Prior Research continuedPrior Research continued How does a genetic predisposition How does a genetic predisposition

manifest itself in criminal behavior?manifest itself in criminal behavior?

Central nervous system (CNS) Central nervous system (CNS) The central nervous system (CNS) represents the

largest part of the nervous system, including the brain and the spinal cord.

A fundamental role in the control of behavior.

CNSCNS

ANSANS

Autonomic nervous system (ANS) Autonomic nervous system (ANS) Controls homeostasisControls homeostasis

Mostly by controlling cardiovascular, digestive Mostly by controlling cardiovascular, digestive and respiratory functions and respiratory functions

Arousal in these areas (CNS and Arousal in these areas (CNS and ANS) lower in criminalsANS) lower in criminals

Research inconclusiveResearch inconclusive SampleSample

Prospective psychophysiological studiesProspective psychophysiological studies Found reduced arousal in criminals in their Found reduced arousal in criminals in their

cardiovascular, electrodermal, and cortical cardiovascular, electrodermal, and cortical response systemsresponse systems

PsychopathsPsychopaths

FocusFocus Underarousal may account for Underarousal may account for

pathological stimulation-seeking in pathological stimulation-seeking in the psychopathic criminalthe psychopathic criminal LykkenLykken EysenckEysenck Raine & VenablesRaine & Venables

HypothesisHypothesis

Underarousal of both the CNS and Underarousal of both the CNS and ANS are related to criminal behavior ANS are related to criminal behavior by relating psychophysiological by relating psychophysiological measures recorded at age 15 and 24measures recorded at age 15 and 24

MethodsMethods

101 male schoolchildren101 male schoolchildren About 15 years oldAbout 15 years old Tested in 1978 and 1979Tested in 1978 and 1979 3 different schools3 different schools

SecondarySecondary GrammarGrammar ComprehensiveComprehensive

Methods continued…Methods continued…

Criminal statusCriminal status 1988 search1988 search Subjects found guilty and sentenced Subjects found guilty and sentenced

were classified as criminalwere classified as criminal 1717 Offenses ranged in severity from theft to Offenses ranged in severity from theft to

injuryinjury Most common offenses burglary and theftMost common offenses burglary and theft

Pyschophysiological Pyschophysiological RecordingRecording

Skin conductanceSkin conductance Reflects central nervous system’s Reflects central nervous system’s

stimulation of the sympathetic nervous stimulation of the sympathetic nervous system system

Part of the autonomic nervous system that Part of the autonomic nervous system that prepares the body for physical activityprepares the body for physical activity

Nonvolitional preparation of the organism Nonvolitional preparation of the organism for emergency situations for emergency situations

How much the fingers sweatHow much the fingers sweat

Recording continued…Recording continued…

Heart rateHeart rate Lower resting heart rate associated Lower resting heart rate associated

with criminalitywith criminality Recorded with polygraph and Recorded with polygraph and

electrocardiographic preamplifierelectrocardiographic preamplifier

Recording continued…Recording continued…

EEGsEEGs Measure activity in the brainMeasure activity in the brain

ProcedureProcedure

Subjects informed about equipmentSubjects informed about equipment Electrodes appliedElectrodes applied 2 minute rest period2 minute rest period HeadphonesHeadphones

Series of tones initiatedSeries of tones initiated

FindingsFindings

Criminals had significantly lower Criminals had significantly lower heart rate levels compared to heart rate levels compared to noncriminals noncriminals

Findings continued…Findings continued…

Skin conductanceSkin conductance Criminals had a lower number of skin Criminals had a lower number of skin

conductance NS-SCRs on both handsconductance NS-SCRs on both hands

Findings continued…Findings continued…

Findings continued…Findings continued…

EEG PowerEEG Power Cortical underarousal in criminalsCortical underarousal in criminals Slow frequency activitySlow frequency activity

Findings continued…Findings continued…

Criminals had lower levels of arousal Criminals had lower levels of arousal across all measuresacross all measures Appears not to be mediated by social Appears not to be mediated by social

and demographic factorsand demographic factors Other factors?Other factors?

Social factorsSocial factors These findings do not negate the role of These findings do not negate the role of

these factors in the development of these factors in the development of criminalitycriminality

Summary and ImplicationsSummary and Implications

ANS and CNS underarousal seem to play a ANS and CNS underarousal seem to play a role in the development of criminal role in the development of criminal behaviorbehavior Undersousal of skin Undersousal of skin

conductance, heart rate, conductance, heart rate,

and EEGand EEG GeneticsGenetics

May help in the early May help in the early

prediction of antisocial prediction of antisocial

behavior and criminality behavior and criminality

later in lifelater in life