Biological Psychology - The Biological Explanation of Aggression

KEY : Studies/Evidence    Examples

Three Different Types of Aggressive Behaviour:

• Offensive > when an animal physically attacks another > eg Punching
• Defensive > behaviours that are shown in response to either an attack or the threat of one.
• Predatory > when an animal attacks another species in order to gain food

Hypothalamus

• Medial > produces offensive behaviour
• Dorsal > produces defensive behaviour
• Lateral > predatory behaviour (Flynn, Vanegas, Foote and Edwards, 1970
  

Areas of the Brain that are Associated with Aggression

The Midbrain > Contains the Periaqueductal Grey Matter (PAG), and integrates behavioural responses to both interal and external stressors (eg pain/threat)

> (Lonstein and Stern,1998) > Found that lesions inside the midbrains of rats that had recently given birth > there was an increase in aggressive behaviour when they were confronted with what they perceived to be a potential threat (male rats that were unfamiliar to the cage were introduced).

The Amygdala > The centre for impulsivity and the control of emotions, emotional behaviour and motivation. It also integrates both internal and external stimuli > how we react to the environment ( that will potentially lead to aggressive behaviour). 

The Hypothalamus > It controls both the process of homeostasis, as well as maintaining the regulation of hormones. These hormones include those of which regulate sexual function, such as testosterone or osetrogen (testosterone being a contributor to aggressive behaviour). Hormone regulation is more important when looking at aggression.

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