Describe the biological (medical) model of abnormality and evaluate it in terms of its strengths and weaknesses. (12 marks)
The biological model of abnormality assumes that there is an underlining physiological cause of psychological disorders. Such disorders are considered as illness in the same way as the body can be affected by illnesses.
The model includes the idea that genetic factors may be important in psychological disorders. As identical twins are 100% genetically identical and fraternal twins don’t share all of their genes, identical twins might be more similar if a condition is inherited.
Gottesman (1991) conducted a meta-analysis of twin studies, and found that people had a 48% chance of developing schizophrenia if their identical twin had the condition. This reduced to 17% with non-identical twins. This suggests that schizophrenia could have a genetic basis.
Another explanation of abnormality is that it is caused by biochemical imbalance. For example, the dopamine hypothesis suggests that excess dopamine may cause schizophrenia. Evidence for this includes the effects of drugs such as amphetamines, which increase dopamine levels and can…