Biological Approach

• Assumptions


  • All thoughts, feelings and behaviours have a physical basis
  • Everything psychological is at first biological
  • To understand human behaviour we must look at biological structures and processes
• Neurochemical Basis of Behaviour


  = action of chemicals in the brain. The chemical transmission of neurotransmitters. An imbalance in neurochemicals has been implicated in causes of mental illnesses:

  • Serotonin - OCD, depression, aggression
  • Dopamine - schizophrenia
• Genetic Basis of Behaviour

  = study if psychological characteristics are inherited the same as physical characteristics. Concordance rates in twin studies are compared to see if characteristics have a genetic basis. We expect MZ twins to be concordant and DZ twins to not be if characteristics are genetic. (Nestadt - OCD)
• Genotype and Phenotype


  Genotype = genetic make-up

  Phenotype = the way genes are expressed through physical, behavioural and psychological characteristics.

  MZ twins have the same genotypes, but different phenotypes due to lifestyles
• Evolution and Behaviour


  Darwin - natural selection, any genetic behaviour that enhances survival and reproduction will continue in future generations
• Eval : Strength


  The biological approach uses scientific methods of investigation, a range of precise and highly objective techniques (fMRIs and EEGs). Means the approach is based on objective and reliable data.
• Eval : Strength


  Increased understanding of neurochemical processes has allowed for the development of drugs to treat serious mental disorders e.g. antidepressants used to increase levels of serotonin in the brain to reduce depressive symptoms
• Eval : Weakness


  The biological approach suffers from determinism, as it says human behaviour is something that is genetic and we have no control over. But with MZ twins concordance rates being lower than 100%, it shows that phenotype is heavily influenced by the environment. Rejects the idea of free will and says we are predetermined to act a certain way. Too simplistic and ignores effects of environment