Biological approach

• Assumptions of the Biological Approach

  • Everything psychological is at first biological.
  • All behaviour can be explained through genes, hormones, neurotransmitters, nervous system, brain structure and evolution. 
  • The mind lives in the brain
  • All thoughts, feelings and behaviour have a PHYSICAL biological basis.
  • This is in contrast to the cognitive approach that sees mental processes of the MIND as separate from physical BRAIN.
• Behaviour has a neurochemical basis

  • Neurochemistry can explain behaviour
  • Neurotransmitters transmit messages from one neuron to the next by travelling across the synapse
  • Different levels of neurotransmitters can affect our behaviour 
  • For example, high levels of dopamine are linked with the development of OCD.
• The genetic basis of behaviour

  Twin Studies and Genetic Basis

  • Twin studies determine the genetic basis of traits like musical ability, depression, and football ability.

  • Concordance Rate: The extent to which both twins share the same characteristics.

  • Identical twins (MZ) show higher concordance rates than non-identical twins (DZ) due to 100% gene sharing.

  • Example: 50% concordance rates for aggression, 19% for DZ twins.

  • Supports a genetic basis for aggression, but concordance rates are rarely 100%, indicating environmental factors may also play a role.
• Genotype and phenotype

  • Genotype: a person’s actual genetic make-up.
  • Phenotype: the way that genes are expressed through physical, behavioural and psychological characteristics.
  • How the genotype is expressed is influenced by the environment.
  • E.g. identical twins may share 100% of their genes, but may look different because one has exercised more, or has dyed hair, etc.
  • So despite having same genes (genotype), the way these genes are expressed (PHENOTYPE) is different.
• Evolution and behaviour

  • Darwin (1859) proposed the theory of natural selection 
  • Any genetically determined behaviour that enhances survival and reproduction will be passed on to future generations
  • Such genes are described as adaptive and give the possessor and their offspring advantages
  • For example, attachment behaviours in new-borns promote survival and are therefore adaptive and naturally selected
• • One strength of the biological approach is the use of scientific methods
  • The biological approach uses experimental methods as its main method of investigation
  • Experimental studies take place in highly controlled environments and use sophisticated imaging and recording techniques, including PET and fMRI scanning
  • This means that the biological approach is based on reliable data and increases the validity of the approach
• • Another strength is its application to the treatment of psychological disorders 
  • Research into the role of neurochemical imbalances in depression has led to the development of drug treatments which correct this imbalance to minimise depressive symptoms
  • For example, SSRIs stop the reuptake of serotonin in the synapse, treating the symptoms of depression
  • This matters because the biological approach has helped improve the lives of many sufferers of depression by providing suitable drug treatments
• • However, one criticism of the biological approach is that it is reductionist
  • The biological approach is reductionist because it explains behaviour by breaking it into its smallest components, e.g. genes, neurotransmitters and hormones
  • For example, the biological explanation of depression suggests that depression is caused by low serotonin, while ignoring cognitive, emotional and cultural factors
  • This matters because there are other factors that can contribute to depression and the biological approach ignores all of these other factors
• • A final criticism of the biological approach is the danger of genetic explanations
  • Recent research has found a genetic basis for criminal behaviour which has led to concerns about how this information might be used
  • For example, critics claim that this may lead to genetic screening to identify people at risk of criminality which could lead to discrimination against those people
  • This matters because individuals may be unfairly labelled as criminals because of their genes