Aggression: A Multivariate
Approach: Biological Influences
• Hormones: Testosterone, low
serotonin.
• Olweus: 15-17 year-old boys with high
testosterone higher in aggression
− Linked with irritability
− Anger is a prime emotion of aggression
• Females rats or monkeys injected
with testosterone are more
aggressive.
Aggression: A Multivariate
Approach: Biological Influences
• Hormones: Testosterone, low
serotonin.
• Olweus: 15-17 year-old boys with high
testosterone higher in aggression
− Linked with irritability
− Anger is a prime emotion of aggression
• Females rats or monkeys injected with
testosterone are more aggressive.
• Sensitive periods for testosterone: 5 mos.
after conception and adolesence.
Late adulthood
Conception
5 months
Birth
Adolescence
Aggression: A Multivariate
Approach: Biological Influences
• Temperament Systems
• Aggression as subsystem of
Behavioral Approach (Go)
• Emotionality/Affect Intensity
• Affects proneness to anger, irritability
• Negatively associated with BIS
(Stop), Conscientiousness, and
Affectional System (but
compartmentalization possible)
Aggression: A Multivariate
Approach: Environmental
Influences
• Social Learning: Imitating successful
aggression
• Reinforcement: Successful aggression
brings rewards
• Negative Reinforcement: Aggression
reinforced because it eliminates an
aversive stimulus
− Gerald Patterson: Coercive family
processes a major correlate of children’s
aggression
Aggression: A Multivariate
Approach: Environmental
Influences
Innately Aversive Events
Innate (Natural Clue)
Event
anger, frustration
aggressive
prepotency
Physical Examples: Shock, tail pinch, heat, inflicted pain
David Buss: Cheating spouses, exploitation
Natural Clue: Innate connection between a stimulus and an affective
(evaluative) response: LeDoux’s Low Road: Direct connection to the
amygdala
Stimulus
Response+ (tender touching, sweet)
Stimulus
Response
—
(Shock, etc.)
Aggression: A Multivariate
Approach: Environmental
Influences
Aversive Stimulation: Events Perceived
as Aversive; LeDoux’s High Road via
prefrontal cortex
Event
Cognitive appraisal in terms of interests and
goals: Boss says you’re fired
Anger, frustration
Aggressive prepotency
Aggressive prepotency
doesn’t necessarily lead to
aggressive behavior
Aggressive prepotency
doesn’t necessarily lead to
aggressive behavior
• Whether aggression occurs
depends temperament and
partly on rational assessment of
costs/benefits
• Conscious, rataional decision
making can inhibit aggression.
Effortful Control and
aggression: The general
aggression model
Anderson and Bushman, 2002.
Prepotent, evolved cues
for aggression: Berkowitz
• Aversive experiences produce tendencies
for fight or flight in animals and humans.
•
•
•
•
•
hot temperatures
shock-induced pain
loud noises
foul odors
Crowded freeways??
Berkowitz, L. (1990). On the formation and regulation of anger and aggression: a cognitiveneoassociationistic analysis. American Psychologist, 45, 494–503.
Evolutionary Psychology and
Aggression:
David Buss
Where’s
the
pfc?
• Motives for aggression: Status, reputation, honor and
sexual jealousy as key motives for aggression.
• Adaptive problems “to which aggression might have
evolved as a solution” (p. 608):
•
•
•
•
•
•
•
Co-opting resources held by others
Defending against attack
Inflicting costs on intrasexual rivals
Negotiating status and power hierarchies
Deterring rivals from future aggression
Deterring long-term mates from sexual infidelity
Reducing resources expended on unrelated children.
• Costs (e.g., possibility of retaliation) built into the
module.
•
•
Buss, D. M., & Shackelford, T. K. (1997). Human aggression in evolutionary
perspective. Clinical Psychology Review, 17, 605–619.
Duntley, J. D., & Buss, D. M. (2004). The evolution of evil. In A. G. Miller (Ed.), The
Social Psychology of Good and Evil. New York: Guilford
Buss: Impulsivity as design
feature of aggression as
an evolved module
• After being beaten, “I had stone hatred for him, and I
righteously couldn’t wait to see the look on his face when I
blew him away. As soon as he popped out of the liquor store
door, I charged right up to him, rammed the barrel in his
chest, and pulled the trigger” (in Duntley & Buss, 2005, p.
xxx).
• “Effective strategies sometimes require immediate action.
Ponderous time delays and real-time extended reflection
would result in failure. Stated differently, we propose that
“impulsivity” is actually a design feature of certain
adaptations that promotes their tactical effectiveness. The fact
that they appear to external observers to be products of the
lack of judicious reflection may speak to the profound
inability of human intuitions to grasp the logic of evolved
design, or to our moral judgments that classify certain
strategies as good or bad. Speedy, immediate, real-time
responses can be the product of adaptive design rather than
Explicit processing and
Aggression
• Costs and benefits calculated via explicit
prefrontal mechanisms.
• Explicit assessments of costs/benefits influence
aggression (Tedeschi & Felson, 1994)
• Aid for victim, retaliation
• Likelihood of being caught (e.g., DNA
fingerprinting)
• Penalties at law
• PFC is involved in active inhibition of
prepotent subcortical impulsive aggression.
PFC Inhibition of sub-cortical
aggression impulses:
Damasio; Anderson et al.
• Patients with damage to the ventromedial prefrontal cortex
are driven by immediate rather than long-term rewards
• Children with damage in this area have immature, egocentric
moral reasoning and are prone to stealing and aggression.
Damasio’s “somatic marker” hypothesis proposes that the
deficit stems from the lack of inhibitory emotions normally
attached to negative future possibilities.
• Patients with prefrontal damage originating in infancy
exhibited a general lack of conscientiousness (lack of
dependability, inability to plan for the future, proneness to
immediate rewards rather than long term goals), impulsive
rather than instrumental, goal-directed aggression, and lack
of guilt for transgressions against others.
•
•
Damasio, A. R. (1994/2000). Descartes’ error: Emotion, reason, and the human brain. New York: Quill
(HarperCollins).
Anderson, S. W., Bechara, A., Damasio, H., Tranel, D., & Damasio, A. R. (1999). Impairment of social and
moral behavior related to early damage in human prefrontal cortex. Nature Neuroscience 2, 1032–1037.
PFC Inhibition of sub-cortical
aggression impulses: Raine et al.,
1998
•
•
•
•
•
•
Impulsive murderers had relatively lower left and right prefrontal
functioning and higher right hemisphere sub-cortical functioning.
Predatory murderers whose crimes involved planning and
deliberation had prefrontal functioning that was more equivalent to
comparisons, while also having excessively high right sub-cortical
activity.
Results “support the hypothesis that emotional, unplanned impulsive
murderers are less able to regulate and control aggressive impulses
generated from sub-cortical structures due to deficient prefrontal
regulation” (p. 319).
Both impulsive and predatory murderers have “excessive subcortical
activity” (p. 319)—what one might term “modular aggression.”
Predatory murderers are better able to control these impulses
stemming from subcortical areas because of adequate prefrontral
functioning.
Raine, A., Meloy, J. R., Buhrle, S., Stoddard, J., LaCasse, L., & Muchsbaum, M. S. (1998). Reduced
prefrontal and increased subcortical brain functioning assessed using Positron Emission Tomography in
predatory and affective murderers. Behavioral Sciences and the Law, 16, 319–332.