Biological approach

• Biological approach

  Suggests that everything psychological is at first biological, so to fully understand human behaviour, we must look to biological structures and processes within the body
• Neurochemistry


  The action of chemicals in the brain
• Genotype

  A person's actual genetic make-up
• Phenotype

  The way that genes are expressed through physical, behavioural and psychological characteristics
• Despite having the same genes, the way identical twins' genes are expressed (the phenotype) is different
• This illustrates what many biological psychologists would accept, that much of human behaviour depends upon an interaction between inherited factors (nature) and the environment (nurture)
• Evolution and behaviour

  The theory of natural selection - any genetically determined behaviour that enhances an individual's survival (and reproduction) will continue in future generations
• If the individual survives but does not reproduce, the traits do not remain in the gene pool for successive generations
• Strengths of the biological approach


  • Real-world application (e.g. use of psychoactive drugs to treat mental disorders)
  • Use of scientific methods of investigation (e.g. scanning techniques)
• Limitations of the biological approach

  • Biological determinism - seeing human behaviour as governed by internal, genetic causes over which we have no control
  • Ignoring the mediating effects of the environment
• Antidepressant drugs do not work for everyone, and their effects are 'mainly modest', challenging the value of the biological approach
• The biological approach advocates a form of genetic determinism in its assumption that much of our behaviour is directed by innate influences
• The biological approach has revolutionised the treatment of mental disorders through the development of drug therapy which regulates chemical imbalances in the brain