Biological Contributions
Explaining autism, sex assignment & gender behaviour
Explaining autism using biological concepts
· Autism can be explained by the biological approach as an ‘extreme male brain’ disorder.
· Characteristics which define autism include difficulty in communication and making friends, liking routines and non-severe social withdrawal.
· Autism affects male children more than female children (1:10 ratio).
· Simon Baron-Cohen noted that autistic people seem to have an overemphasis on male brain features e.g. their systemising ability and inability to empathise.
· It is suggested that increased levels of testosterone in the womb at around 8 weeks may cause the growth of an extreme male brain.
· Society benefits from understanding the cause of autism so that autistic children can receive the help they need to develop as normally as possible.
Strengths of this explanation
- Scientific evidence from PET/MRI scans have shown differences in brain structure between autistics and non-autistics, such as a larger corpus callosum and amygdala.
- Methodologies used (e.g. brain scans) are objective and reliable.
- Explanation seems to be valid - the ‘extreme male brain’ explanation fits with many features of autism e.g. the inability to empathise.
Weaknesses of this explanation
- Because brain structure is fixed (due to nature), any biological therapy is unlikely to be effective whereas an environmental cause (nurture) would be more treatable.
- The theory is reductionist; it is possible that there are environmental causes that contribute to the disorder which can occur before or after birth. These factors are not taken into account.
Explaining sex assignment and gender behaviour
- Genes are a blueprint for physical and behavioural characteristics
XX - female XY - male
- Research has also found other patterns such as XXY (Turner’s Syndrome) and XO (Klinefelter’s Syndrome).
- Genes trigger the production of hormones which in turn trigger the male or female development
- Differences occur when hormones are not released normally (in the womb).
- For example, Mullerian inhibiting substance (MIS) might be secreted without androgen secretion meaning the individual would have neither male nor female internal features; conversely, a lack of MIS and androgen secretion would lead to both male and female structures.
- Gender behaviour is also explained by by brain differences e.g. brain lateralisation.
- In our society sex assignment is very important as many judgments about people are made on the basis of their gender.
- The biological basis of the explanations also has led to the development of some treatments, usually hormone therapies.
Strengths of this explanation
· Scientific evidence from PET/MRI scans have shown differences in brain structure, such as in lateralisation, between males and females.
· Evidence from animals, brain scans and DNA testing of humans is scientific, objective and reliable.
· There is predictive validity - gene structure predicts the type of development and those with that type of development do show the related gene structure.
Weaknesses of this explanation
- Theory is reductionist - focuses on nature while ignoring the influence of nurture.
- Much of gene research involves animal studies so results may not generalise to humans.
- Theory has led to the development of potential treatments, e.g. hormone therapy.