Biological

• Twin studies have found that 68% of identical twins shared OCD as opposed to 31% of non-identical twins. If we assume that both types of twins share the same environment, then it must be concluded that shared genetics have an impact on behaviour.
• Dopamine is a neurotransmitter associated with drive/motivation.
• The biological approach assumes that everything psychological is at first biological. All our thoughts and feelings have a physical basis. Differences in people are due to differences in genotype or neurochemistry.
• Humans have approximately 20000 genes. Biological psychologists believe that genes can influence behaviour as well as physical appearance.
• Your genotype is all the genes you have. Your phenotype is the genes that have actually manifested themselves physically due to dominance or environment.
• We have cells in our nervous system that communicate biochemical messages across our synapses. These can affect our behaviour, e.g. dopamine.
• Many of our behaviours were adapted through evolution for our survival long ago. These are mismatched for our modern world. Some behaviours are passed on because they are more well adapted for survival and hence procreation (natural selection) and some because they are more attractive to the opposite sex (sexual selection).
• The approach has a positive approach to treatment as it has led to medication that can help people with mental illness. These mean that symptoms can be controlled, for example, some symptoms of schizophrenia are linked to high dopamine and medication can block some dopamine from being communicated through neurons. This helps people with schizophrenia to lead a more normal and less disrupted life.
• The approach is quite scientific as the use of technical equipment such as brain scanners allows empirical data to be produced. Also, the use of animal research means conditions can be highly controlled which results in high ecological validity. However when applying this to humans they must rely on correlations.
• The biological approach is reductionist as it reduces human behaviour to a single cause. This is a weakness as there are many factors such as environment that can impact someone's behaviour/mental health.
• The applications of the biological approach have in the past led to eugenics which is very socially sensitive.