AO3

• The animal study methodology raises ethical debate, and some argue that complex human behaviour cannot be replicated in non-human animals like rats, and thus cannot be investigated.
• It uses scientific research methods such as EEGs, fMRI and PET scans and twin studies. These produce objective data which can be replicated and peer reviewed.
• It could be argued that twin studies do not separate nature and nurture because twins are raised and live in the same environment and the difference in the concordance rate found between MZ and DZ twins could be due to the fact that MZ twins are treated more similarly by their parents than DZ twins because they look more similar. Also we usually do not find 100% concordance rate in MZ twins for mental disorders which indicates that environmental and social factors must be involved in the development of these disorders.
• It could be argued that the imbalance in neurotransmitters such as low serotonin in depressed individual is the consequence rather than the cause of depression because the brain is a plastic organ which changes with the way we use it so it could be that the depressed thinking causes the low level of serotonin observed.
• Furthermore the imbalance in neurotransmitters is usually not directly observed it is deduced from drug trials where patients are given the drugs and seen to improve so we deduce that it was the lack of the neurotransmitters which cause the disorder but this might not be the case.
• Nature/Nurture - The biological approach is firmly on the nature side of the debate; however, it does recognise that our brain is a plastic organ which changes with experience in our social world so it does not entirely deny the influence of nurture.
• Idiographic/Nomothetic - It is nomothetic approach as it focuses on establishing laws and theories about the effects of physiological and biochemical processes that apply to all people.
• Free will/Determinism - The biological approach is deterministic as it sees our behavior as caused entirely by biological factors over which we have no control. This encourages people not to take responsibility for their own actions and blame their genetic makeup.
• Holism/Reductionism - Reductionist as it reduces our behavior to the outcome of the actions of genes and other biological processes neglecting the effects of childhood and our social and cultural environment.