The Biological Approach

• Assumptions of the Biological Approach


  • Mind lives in the brain, all thoughts, feelings and behaviours have a physical basis - biological component
  • Everything physiological is at first biological - look at genes, neurochemistry and biological structures to understand behaviour
  • Behaviour is influenced by neurochemistry (neurotransmitters, hormones)
• Role of genetics in the biological approach

  • Genetic makeup of individuals can influence their behaviour
  • Twin studies
  • Observe the influence of genes by studying monozygotic twins who share an identical genetic code
  • High concordance rate/ correlation between identical twins' behaviour may suggest a genetic component is involved
• The Biological Approach - Suggests human behaviour is caused by biological factors like genes, neurotransmitters, physical structures (NS&brain)
• Role of evolution in the Biological Approach

  • Any genetically determined behaviour that enhances an individuals' survival will continue in future generations
• Genotype

  Genetic makeup of an individual
• Phenotype


  How behaviours & traits become expressed as a result of the genotype mixing with the environment
• What is PKU

  Phenylketonuria (PKU) is rare genetic disorder that can be detected in babies using a heel prick test.

  Expression of PKU

  Genotype → PKU Gene

  Genotype + Environment → Phenotype

  PKU Genes + diet → Brain damage/no brain damage
• Evaluation of the Biological Approach


  + Uses highly scientific methods (brain scans, twin studies)

  Using twins = strong control over variables. ↑ Internal Validity. Draw concl. confidently

  + Effective practical appl. Understanding of biochem processes led to drug treatments

  - Relies on twin studies to demonstrate genetic basis of behaviour. Twins share environments. Hard to differentiate whether genes/environment have the biggest effect

  - Assumes certain biological factors determine particular behaviours and this can't be changed. Reductionist