Psychology B1 - biological approach to explaining aggression Flashcards
biological explanations: evolution and aggression
-individuals in our evolutionary history who were able to survive to adulthood were more likely to reproduce
-would pass on the genes that contributed to the behaviours that made survival possible - could’ve been aggression
-example, aggressive individuals may have been more successful in competition for limited resources such as food and mates
-men = more likely to pass on their genes if they were able to i
‘retain’ partners
-example, prevent them from reproducing with rivals
-was achieved through aggressive mate retention strategies such as using physical violence to prevent a partner from meeting other men
biological explanations: brain structures and aggression
-limbic system = a collection of several structures in the brain that regulate our emotional behaviour -the limbic structure most closely associated with aggression is the amygdala
biological explanations: brain structures and aggression — amygdala
-sensitivity of the amygdala is an important predictor of aggressive behaviour - the more sensitive the person’s amygdala, the more aggressive they are
-because the amygdala plays a key role in how we assess and respond to threats in the environment
-example, aggressive people tend to have amygdalas that react quickly and strongly to threatening stimuli (Gospic et al. 2011)
biological explanation: biochemistry and aggression — testosterone
-male sex hormone responsible for the development of masculine features
-it’s linked to aggression mainly because men are generally more aggressive than women and also have much higher testosterone levels
-example, men become more aggressive towards each other at a time in development (after age 20 years) when testosterone levels are highest (Daly and Wilson 1988).
biological explanation: biochemistry and aggression — serotonin
-neurotransmitter that affects aggression mainly through its influence on an area of the brain called the orbitofrontal cortex (OFC)
-low levels of serotonin in the OFC disrupt the activity of neurons, producing emotional instability and reduced behavioural self-control
-leads to an increase in impulsive behaviours, including aggression (Denson et al. 2012)
biological explanation: biochemistry and aggression — dopamine
-neurotransmitter that influences aggression when people are in competition over resources
-dopamine = the brain’s own reward chemical
-example, imagine there are two drivers but only one parking space -both people are in conflict with each other and have high dopamine levels because they anticipate winning the competition
-motivates the use of aggression to gain victory
-potential rewards a parking space and a dopamine boost encourage risk-taking and impulsive behaviours, including aggression
biological explanation: biochemistry and aggression — cortisol
-stress hormone which also plays a role in aggression in conjunction with testosterone
-high levels of testosterone lead to aggressive behaviour
-this is only true when cortisol levels are low
-When cortisol is high, testosterones influence on aggression is blocked (Carré and Mehta 2011)
biological explanations: genetics and aggression — MAOA gene
-MAOA gene controls the activity of an enzyme called monoamine oxidase A
-this enzyme ‘mops up’ neurotransmitters in the brain after a nerve impulse has been transmitted across a synapse
-gene comes in two variants, low-activity and high-activity
-people who inherit the low-activity variant (MAO-L) have low activity of the enzyme, so their neurotransmitter functions = disrupted
-have often been found to be highly aggressive
biological explanations: genetics and aggression — SRY gene
-SRY gene has an indirect influence on aggression through masculinisation of the embryo
-the SRY gene activates testes development that triggers testosterone production in the womb (and at puberty)
-testosterone may partly explain the common finding that men tend to be more aggressive than women
evaluation: practical applications (+)
-real-world benefits from understanding biological factors in aggression
-biological factors offers a target for interventions
-example, a better understanding of the roles of hormones and neurotransmitters could lead to the development of drugs to control and even reduce aggression
-Intervention doesn’t have to be biological
-recognise that genes contribute to aggression, but this influence can be partly counteracted by providing social and psychological support to ‘at risk’ families
-biological approach provides potential ways of reducing the costs of aggressive behaviour to individuals and societies
evaluation: research support (+)
-research studies support the biological factors on this spread
-brain scans show high levels of amygdala activity when individuals view images of angry faces (Coccaro et al. 2007)
-Serotonin-related chemicals are found in lower amounts in violent impulsive offenders compared with non-violent offenders (Virkkunen et al. 1994)
-men who use mate retention strategies in heterosexual relationships are more likely to be physically violent towards their partners (Shackelford et al. 2005)
-there is a lot of research to suggest that biological factors play a key role in aggressive behaviour
evaluation: complex picture (-)
-there are many causes of aggression
-the biological factors don’t operate in isolation but interact with each other
-example, brain structures and neurotransmitters
-there are several other biological factors involved in aggression that are not covered here, such as another neurotransmitter called GABA and other brain structures apart from the limbic system
-these biological factors contribute to aggressive behaviour, but they interact with non-biological factors which are equally important.
-shows that the causes of aggression are extremely complex and greater than just any single biological factor
