02 _ Aggression

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Aggression & Sex

Biological Motives

Reproduction & Aggression

As basic to survival as hunger & thirst!

And also affected by internal & external factors

But, NOT homeostatic

So, more variable, and more sensitive to environmental circumstances

Also, they involve more than one organism

Learning adds big complexities

Instinct Re-Examined

James & McDougall versus Kuo

Classical ethology: Lorenz, Tinbergen

Action patterns

Releasing stimulus


Different to motivational states, responses are not goal-directed but _______________

Sexual activity and aggressive behavior are viewed as largely innate and intimately related

But in humans the case is much less clear

Although there might be something to it


Innate behaviors, _________-specific

Triggered by specific stimulus inputs

Means untaught, not inflexible

Aggression

Behavior against another individual with the intention of committing harm

Socially unacceptable behavior

Aggression varies in forms

It also differs in functions

E.g., reactive vs proactive

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Aggression

Most likely between ages 1 and 3

Violent crimes most likely btw 15 and 30

As consistent as IQ as individuals grow up

Aggression

But, how do you study it?

Early lab research: Retaliation Paradigm

Would participants deliver a painful shock to another person?

The Functions of Aggression

Six evolutionary hypotheses:

___________ resources of others

Defend against ___________

Inflict costs on ___________ rivals

Negotiate _______and _______hierarchies

Deter rivals from future aggression

Deter long-term mates from infidelity

Aggression: Internal Influences

Maybe they are both responsive to same internal influences

Heritability results are mixed

Maybe, impulsivity is what is inherited?

Serotonin: abnormally low levels associated with impulsive aggression: inhibition?


Mostly in males androgens? (Testosterone)

Many species: little or no aggression before puberty and little aggression outside breeding season

Aggression most common among _________; castrated male rats are ______ aggressive

Reversed if you inject testosterone


In adult humans, role of hormones is less clear

Human males commit more violent crimes But is it hormones? Culture? Something else?

Correlation with testosterone is _______

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Testosterone injections increase subjective feelings of hostility

Testosterone increases after winning at fights or competitions and decreases after defeat


Maybe testosterone does not cause aggression, but important for its expression

Testosterone involved in social status?

Link is not to aggression but to social dominance

Also, what about female aggression?

Inconclusive results


Difference might be in the preponderance of physical harm

But, again, is it hormones or culture?


Neural regions underlying aggression are sensitized by testosterone

In non-humans, particular neural circuits elicit a tendency to aggression

Sensory detection amygdala medial hypothalamus PAG; motor responses in brain stem

In humans: sometimes anger when amygdala stimulated directly, but no aggression


Lorenzs Hydraulic Theory: if action pattern not released for some time, it may be triggered at the slightest provocation

Similar to Freuds notions

Catharsis hypothesis

Evidence is quite contrary

Aggression: External Influences

So, aggression is highly context-specific

Different systems of aggressive behavior

1. Predatory

2. Intermale

3. Fear-induced

4. Territorial

5. Maternal

6. Irritable

7. Sex-related

8. Instrumental

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If physically harmed, participants would retaliate in kind

If they believed no further retaliation in the future more shocks than received

Massive retaliation tends to decrease or terminate aggressive exchanges


Pain

Heat

Weapons (Berkowitz & Le Page, 1967)

Crowding

Victims provoking attack??

Obedient aggression (Milgram)

Social rejection

Provocation

Violent media?

Ego depletion

Aggression, Learning & Culture

Most potent determinant of aggression seems to be ____________

Despite frequent cases, all in all we are less violent today than we were centuries ago

Theories of Aggression

The Frustration and Aggression theory

Blocking of goal directed behavior leads to aggressive behavior

But does every frustration lead to aggression?


Maybe frustration leads to a number of behaviors, one of which is aggression

So, why aggression? Maybe because of learning!

Classical and operant conditioning

Discrimination and generalization

Social learning (Bandura), remember the Bobo Doll?


Excitation-transfer theory (Zillmann)

Physiological arousal dissipates slowly

If two arousing events in a short period of time, arousal from the first may ____ to that to the second one.

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Information processing theories

Script theory: Aggression-related mental representations and action plans are learned by observing others

Hostile attributions

Cognitive neoassociation: Aversive events negative affect fight and flight associations


The general aggression model (GAM)

Proximate versus ultimate goals

Four dimensions: (a) degree of hostility, (b) automaticity, (c) harm vs self-benefit, (d) consideration of consequences

Theories of Aggression: The I3 theory

Instigation: discrete events that frequently increase an aggressive urge

Impellance: factors that increase the likelihood of experiencing an aggressive impulse

Inhibition: Individual difference or situational features that diminish the likelihood of an aggressive urge

Theories of Aggression: The I3 theory

How do these combine additively and interactively to increase or decrease aggression?

Aggression most likely when instigators and impellors are high and inhibitors are low

E.g., provocation (instigator) is likelier to lead to aggression if you have trait anger (impellor) and are disinhibited


So, again, at least in humans, we have a motivational state

It widens the range of effective stimuli!

Negative feedback loop? Sometimes

But, not homeostatic

No energy is built up, no other physiological imbalance

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02 _ Aggression