Biological explanations of aggression

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Biological explanations of aggression

• Brain structure

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Learning objectives

• Evaluate the contribution of research into neural
  influences on behaviour.

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The hypothalamus

• Bard Mountcastle (1953)
• Looked at rage in cats caused by detaching the
  hypothalamus from the cortex.

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Flynn 2006

• Stimulation of the lateral hypothalamus in cats
  made predatorial aggression more likely.
• Stimulation of the medial hypothalamus led to
  vicious attack behaviour.

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The amygdala
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The amygdala

• Zagrodzka et al. (1998)
• Damage to the central nucleus of the amygdala in
  cats led to predator-like attacks.
• Potegal (1991) hamsters have more active neurons
  in and around the medial nucleus of the amygdala
  during acts of aggression but no increases in
  other areas.

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The amygdala

• In humans, if an amygdalectomy is carried out,
  violent behaviour is reduced, but emotions are
  lost.

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Aggression and brain structure

• Two areas of the brain specifically thought to be
  involved in aggressive behaviour.

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Phineas Gage