MAASTRICHT UNIVERSITY
PSY3384 Aggression
Elective course
Year 2018/2019
Table of contents:
Task 1: what is aggression? ..................................................................................................................... 2
Task 2 Aggression assessment............................................................................................................... 22
Task 4 Origins of aggression: Nature ..................................................................................................... 37
Task 5 Origins of aggression: Nurture ................................................................................................... 52
Task 6 Therapy for aggression ............................................................................................................... 71
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Task 1: what is aggression?
What is aggression?__________________________________________________________________
Anderson, C., and Bushman, B. (2002). Human aggression
Basic definitions
Aggression - any behaviour directed toward another individual that is carried out with the proximate
(immediate) intent to cause harm. In addition, the perpetrator must believe that the behaviour will
harm the target, and that the target is motivated to avoid the behaviour.
◼ Accidental harm is not aggressive because it is not intended. Harm that is an incidental by-
product of helpful actions is also not aggressive, because the harm-doer believes that the
target is not motivated to avoid the action. The pain administered in sexual masochism is
also not aggressive.
Violence - a form of aggression that extreme harm as its goal. All violence is aggression, but
aggression is not always violence.
Hostile/ reactive aggression - being impulsive, thoughtless (unplanned), driven by anger, have the
ultimate motive of harming the target and occurring as a reaction to some perceived provocation.
Instrumental/ proactive aggression is conceived as a premeditated means of obtaining some goal
other than harming the victim and being proactive rather than reactive.
A recent analysis modifies these definitions in 2 ways:
Kempes, M., Matthys, W., De Vries, H., and Van Engeland, H. (2005). Reactive and proactive aggression in children : A
review of theory, findings and the relevance for child and adolescent psychiatry.
Definition of aggression
Because aggressive behaviour occurs in the context of other types of antisocial behaviour, the two
terms are often aggregated. Clear definitions:
◼ Aggression - behaviour deliberately aimed at harming people and/or objects. This can be
harming physically (kicking), psychologically (humiliating) and relationally (malicious
gossiping).
◼ Antisocial behaviour - behaviour by which people are disadvantaged and basic norms and
values are violated; lying, stealing and truancy (spijbelen).
➔ Aggressive behaviour is a specific form of antisocial behaviour.
Subtypes of adult aggression
In adult psychiatry there are two lines of research that reflect this distinction into two types of
aggression: impulsive forms of aggression/ reactive aggression and non- impulsive aggression/
proactive aggression.
Impulsive/ reactive aggression Non-impulsive / proactive aggression
Explosive and uncontrolled Goal –oriented
High levels of arousal and emotions Low arousal
Aggressive response to a perceived threat or Behaviour that anticipates a reward
provocation
Research has focused mainly on two perspectives: measurement of neurotransmitters like serotonin
and psycho-physiological arousal.
◼ Subjects showing impulsive aggression have lower serotonergic activity than do non-
impulsive individuals as indicated by low levels of these metabolites.
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◼ In general the resting heart rate and skin conductance level are lower in antisocial individuals
(proactive) → might reflect underarousal. Increased or extreme levels of arousal ( high heart
rates and skin conductance) facilitate impulsive aggression.
Subtypes of aggression in children
In 1987, Dodge and Coie [14, 15] introduced the distinction between reactive and proactive
aggression in children. Measurements:
◼ Questionnaires → in order to examine the distinction between reactive aggression and
proactive aggression in children.
◼ Behavioural observations → behavioural observations of playgroup interactions between
peers in laboratory settings.
Younger children are more physical and impulsive in their aggressive behaviour. With age cognitive
ability progresses and the ability to set goals aggressive behaviour becomes more planned and
calculative in nature. Therefore, it is hypothesised that reactive aggression would start at a much
younger age compared to proactive aggression.
Girls are more likely to show relational aggression such as gossiping, whereas boys are more likely to
show overt aggression. Reactive aggression includes mostly overt aggressive behaviour, whereas
proactive aggression is often displayed in a more covert manner. One may therefore expect that boys
show more reactive aggression and girls show more proactive aggression.
Conclusion:
The literature on the measurement in children via questionnaires and behavioural observations
shows that the subtypes can be distinguished but are substantially correlated.
◼ Many children show both types of aggression and only small groups are characterised as
reactive-only or proactive only.
◼ Literature on specific characteristics of the subtypes such as social information processing,
peer status, biological correlates and developmental history shows that the two types of
aggression are related to different kinds of variables in ways that are consistent with their
definitions, suggesting that they form distinct phenomena.
Theories about aggression____________________________________________________________
Anderson, C., and Bushman, B. (2002). Human aggression
Domain specific theories of aggression
Cognitive Neoassociation Theory
Berkowitz proposed that aversive events such as frustration, provocations, loud noises,
uncomfortable temperatures and unpleasant odors produce negative affect. Negative affect
produced by unpleasant experiences automatically stimulates various thoughts, memories,
expressive motor reactions and physiological responses associated with both fight and flight
tendencies. →The fight associations give rise to rudimentary feelings of anger, whereas the flight
associations give rise to rudimentary feelings of fear.
◼ Aggressive thoughts, emotions, and behavioral tendencies are linked together in memory.
◼ Concepts with similar meanings (e.g., hurt, harm) and concepts that frequently are activated
simultaneously (e.g., shoot, gun) develop strong associations.
It also includes higher-order cognitive processes such as appraisals and attributions. If people are
motivated to do so, they might think about how they feel, make causal attributions for what led
them to feel this way and consider the consequences of acting on their feelings. Such deliberate
thought produces more clearly differentiated feelings of anger, fear or both. It can also suppress or
enhance the action tendencies associated with these feelings.
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➔ Provides a causal mechanism for explaining why aversive events increase aggressive
inclinations. This model is particularly suited to explain hostile aggression, but the same
priming and spreading activation processes are also relevant to other types of aggression.
Social Learning Theory
Social learning theory explains the acquisition of aggressive behaviours, via observational learning
processes, and provides a useful set of concepts for understanding and describing the beliefs and
expectations that guide social behaviour.
➔ This theory is particularly useful in understanding the acquisition(verwerving) of aggressive
behaviours and in explaining instrumental aggression.
Script Theory
Huesmann proposed that when children observe violence in the mass media, they learn aggressive
scripts. Scripts are sets of particularly well-rehearsed, highly associated concepts in memory, often
involving causal links, goals and action plans.
◼ Scripts define situations and guide behaviour: The person first selects a script to represent
the situations and then assumes a role in the script. Once a script has been learned, it may be
retrieved at some later time and used as a guide for behaviour.
◼ When items are so strongly linked that they form a script, they become a unitary concept in
semantic memory. Even a few script rehearsals can change person’s expectations and
intentions involving important social behaviours. A frequently rehearsed script gains
accessibility strength in two ways:
o Multiple rehearsals create additional links to other concepts in memory, thus
increasing the number of paths by which it can be activated.
o Multiple rehearsals also increase the strength of the links themselves.
o → a child who has witnessed several thousand instances of using a gun to settle a
dispute on television is likely to have a very accessible script that has generalized
across many situations → the script becomes chronically accessible.
➔ This script is particularly useful in accounting for the generalization of social learning
processes and the automatization of complex perception-judgement-decision-behavioural
processes.
Excitation transfer theory
If two arousing events are separated by a short amount of time, arousal from the first event may be
misattributed to the second event. If the second event is related to anger, then the additional arousal
should make the person even angrier.
Social interaction theory
This theory interprets aggressive behaviour as social influence behaviour; an actor uses coercive
actions to produce some change in the target’s behaviour.
◼ Coercive actions can be used by an actor to obtain something of value (information, money,
goods), to exact retributive justice for perceived wrongs, or to bring about desired social and
self-identities (toughness, competence).
◼ The actor is a decision-maker whose choices are directed by expected rewards, costs and
probabilities of obtaining different outcomes.
➔ Provides an explanation of aggressive acts motivated by higher lever (ultimate) goals. Even
hostile aggression might have some rational goal behind it, such as punishing the
provocateur. This theory provides an excellent way to understand recent findings that
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