BLOA - to what extent does genetic inheritance influence behaviour? Flashcards Preview

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Flashcards in BLOA - to what extent does genetic inheritance influence behaviour? Deck (14):


- behaviour causing pain/harm in others
- labeled as aggression only when the behaviour is intended to cause harm

a doctor giving an injection causes pain but the act isn't aggressive as his intention isn't to harm the individual


genetic inheritance and aggression

- animal studies have shown clear link between aggression and genetic inheritance

Cited studies:
- Bock and Goode (1996)
- Suomi and Lesch (2002)


Bock and Goode (1996) - Aim

investigate effects of serotonin on aggression


Bock and Goode (1996) - Process

2 conditions:
- serotonin inhibited
- control

- low serotonin levels are correlated with aggression
- mice in the first condition had their serotonin receptor sites genetically manipulated via breeding
- by having the gene responsible for producing serotonin receptor proteins removed
- aggression was measured by the amount of bites/attacks


Bock and Goode (1996) - Findings

serotonin-inhibited mice reared without aggressive role models still showed aggressive behaviour


Bock and Goode (1996) - Conclusion

aggression can be correlated with genetics


Bock and Goode (1996) - Evaluation

- tightly controlled
- quantifiable and clear IV/DV
- ethical guidelines for treatment of animals followed
- as animals were bred for experimental purposes


Suomi and Lesch (2002)

- identified a gene that affects effectiveness of processing serotonin
- cerebral spinal fluid of 132 juvenile rhesus monkeys was collected
- analysed for serotonin metabolite traces (high metabolite level = high efficiency of serotonin processing)
- monkeys that had low metabolite levels were more aggressive


extent of influence of inheritance on behaviour

- animal studies have shown clear link between aggression and genetic inheritance
- but it's reductionist and simplistic to assume genes are solely responsible for complex behaviour
- aggression is a complex human behaviour
- unlikely to be the result of one genetic trait
- more likely the result of a combination of environmental and genetic factors
- factors in the environment (e.g. parenting) must always be considered

cited studies:
- Suomi (2002)
- Caspie and Moffitt (2012)


Suomi (2002)

- noted that bullies came from stern mothers while neurotics came from shy mothers
- he took neurotic babies (babies that had nervous dispositions) from neurotic mothers
- gave them to nurturing mothers (supermoms)
- when raised by supermoms, the babies turned out very close to normal
- shows that environment has a clear impact on behaviour


Caspi and Moffitt (2012)

- conducted 26 year longitudinal study
- involved 1036 children born in 1972 NZ
- children inheriting a short version of the gene MAOA were more likely to exhibit aggression
- but this was only in cases where the children experienced an abusive upbringing
- carriers of MAOA who experienced good parenting were usually normal


evaluation of gene research (strengths vs weaknesses)

- helps us determine the effect of particular genes on behaviour

- genes interact with the environment in complex ways
- knowledge about genes is still limited


evaluation of animal studies (strengths vs weaknesses)

- animal studies allow high levels of manipulation that would not be allowed on humans
- findings help us understand biological mechanisms

- caution should be used when generalizing findings
of animal studies to humans


what to write when asked: "to what extent does genetic inheritance influence behaviour?"

- define aggression
- describe + explain the link between genes and aggression -- Bock and Goode (1996), Suomi and Lesch (2002)
- investigate alternate factor (effect of environment on behaviour) -- Suomi (2002), Caspie and Moffitt (2012)
- evaluate studies mentioned
- discuss the ecological validity of genetic research
- weigh benefits and limitations of using genetic research to understand behaviour
- when stating opinions, mention empirical evidence
- form a clear conclusion by discussing the relative importance of genes vs environment on behaviour

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