Outline and evaluate neural and/or hormonal explanations into aggression.
-Neural influences of aggression involve the limbic system (amygdala and hippocampus) and
serotonin deficiency hypothesis.
-The limbic system is an area of the brain that helps to coordinate behaviours that satisfy
motivational and emotional urges such as aggression. It plays a key role in how an organism
responds to environmental threats and challenges and thus is believed to be the key factor in
whether we respond aggressively or not to an external stimulus. The two key structures in the
limbic system that are associated with aggression are the amygdala and the hippocampus.
-The amygdala is responsible for attaching emotional significance to sensory information.
Damage to the amygdala could lead to information not being processed correctly making the
individual prone to aggression. The prefrontal cortex is crucial for regulating social behaviour
and aggressive responses. Damage to the prefrontal cortex would reduce the inhibition of the
amygdala resulting in higher levels of aggression as information cannot be put into a meaningful
context.
-The hippocampus is involved with forming long-term memories and allows animals to
compare the conditions of a current threat with a similar past experience. An impaired
hippocampus prevents the nervous system from putting things into a relevant and meaningful
context. This may cause the amygdala to respond inappropriately to sensory stimuli which may
result in aggressive behaviour.
-Serotonin is a neurotransmitter which typically inhibits the firing of the amygdala (controls fear,
anger and other emotional responses). Serotonin deficiency hypothesis suggests that low
levels of serotonin removes this inhibitory effect meaning that individuals are less able to control
impulsive and aggressive behaviour. As a result, when the amygdala is stimulated by external
events, it becomes more active, causing the person to act on their impulses, and making
aggression more likely. Mann et al. found that drugs that reduce serotonin levels like
dexfenfluramine were found to increase aggression in males (but not females).
-Hormonal influences - Men have higher concentrations of testosterone (hormone produced
mainly by the testes in males, but also occurring in females) compared to women and tend to be
more aggressive suggesting that testerone may make men more aggressive. Male-on-male
aggressive behaviour increases when testosterone concentrations are highest between the
ages of 21-35.
A03
1) Research support for the amygdala- One strength of the amygdala as an explanation for
a neural explanation on aggression is that there is research support by Wong et al
(1997) who found that MRI scans of violent males showed a smaller volume of the
amygdala compared to a control group. This study supports the role of the amygdala as
-Neural influences of aggression involve the limbic system (amygdala and hippocampus) and
serotonin deficiency hypothesis.
-The limbic system is an area of the brain that helps to coordinate behaviours that satisfy
motivational and emotional urges such as aggression. It plays a key role in how an organism
responds to environmental threats and challenges and thus is believed to be the key factor in
whether we respond aggressively or not to an external stimulus. The two key structures in the
limbic system that are associated with aggression are the amygdala and the hippocampus.
-The amygdala is responsible for attaching emotional significance to sensory information.
Damage to the amygdala could lead to information not being processed correctly making the
individual prone to aggression. The prefrontal cortex is crucial for regulating social behaviour
and aggressive responses. Damage to the prefrontal cortex would reduce the inhibition of the
amygdala resulting in higher levels of aggression as information cannot be put into a meaningful
context.
-The hippocampus is involved with forming long-term memories and allows animals to
compare the conditions of a current threat with a similar past experience. An impaired
hippocampus prevents the nervous system from putting things into a relevant and meaningful
context. This may cause the amygdala to respond inappropriately to sensory stimuli which may
result in aggressive behaviour.
-Serotonin is a neurotransmitter which typically inhibits the firing of the amygdala (controls fear,
anger and other emotional responses). Serotonin deficiency hypothesis suggests that low
levels of serotonin removes this inhibitory effect meaning that individuals are less able to control
impulsive and aggressive behaviour. As a result, when the amygdala is stimulated by external
events, it becomes more active, causing the person to act on their impulses, and making
aggression more likely. Mann et al. found that drugs that reduce serotonin levels like
dexfenfluramine were found to increase aggression in males (but not females).
-Hormonal influences - Men have higher concentrations of testosterone (hormone produced
mainly by the testes in males, but also occurring in females) compared to women and tend to be
more aggressive suggesting that testerone may make men more aggressive. Male-on-male
aggressive behaviour increases when testosterone concentrations are highest between the
ages of 21-35.
A03
1) Research support for the amygdala- One strength of the amygdala as an explanation for
a neural explanation on aggression is that there is research support by Wong et al
(1997) who found that MRI scans of violent males showed a smaller volume of the
amygdala compared to a control group. This study supports the role of the amygdala as
