the biological approach

• assumptions

  • everything psychological is at first biological so all thoughts, feelings and behavior has a biological cause
  • studies how biological structures and processes within the body such as genes, neurochemistry and the nervous system impacts our behavior
  • the mind lives in the brain and is not separate
• the biological approach studies the influence of genes, brain, endocrine system, nervous system and the evolutionary theory on behaviour
• DNA carries the code that determines the characteristics of every living thing. Genes are short sections of DNA found on chromosomes.
• Our genes are inherited from our parents, we inherit pairs of genes one from the each. each of these genes in a pair is known as an allele
• we can study genomes by looking at genes under a microscope. This may be specific genes or variants of them which are linked to certain characteristics or we can study family relations and look at characteristics
• concordance rate

  • rate of similarity between 2 individuals for a specific trait
  • it is used to establish if there may be a genetic link between behaviours or traits with family members
  • e.g. if one twin has a trait it is the possibility that their twin will also have it
  • it is a percentage
• study investigating concordance rate

  1. concordance rate of 2 groups are compared
  2. twin pairs are often used. 100 participants with a condition or characteristic who have a twin are gathered
  3. they are twin A and their twin is twin B
  4. twin B is questioned
  5. the concordance rate is the percentage of twin B who have the condition of twin A
• adoption studies involve comparing the concordance rates of adopted children and non-adopted children. If they are higher in adopted children than non-adopted children then this supports the idea that genetics plays a part in the development of the condition/characteristic
• methods for investigating genetic causes of behaviour

  • twin studies
  • family studies
  • adoption studies
• what are twin studies for concordance rate


  compares concordance rate for the same trait between monozygotic and dizygotic twins
• what are family studies for concordance rate


  compares concordance rates for similar traits between different pairs of family members
• what are adoption studies for concordance rate 


  compares concordance rated for similar traits between pairs in an adopted family and pairs in the biological one
• adoption studies identify the concordance rate between:

  1. adopted child and biological parent
  2. adopted child and adoption parents
• if the concordance rate with adopted parents is higher than with the biological parents there is evidence that behaviour/trait is due to environmental factors
• if the concordance rate with biological parents is higher than with the adopted parents there is evidence that the behaviour/ trait is due to genes.
• conclusion 


  our genetics alone do not determine our traits or disorders therefore there must be some interaction with the environment.

  This suggests that interventions should have an environmental focus as this is something we can control
• the genotype is the genetic makeup of an organism, they only determine the potential for characteristics
• phenotype is the observable characteristics of an individual and are the results of the interaction between genetics and environmental factors
• has real-world application as it increases the understanding of neurochemical processes in the brain and is associated and is used in treatment of mental disorders
• Andrea Cipriani et al 2018


  compared 21 antidepressant drugs and found wide variations in effectiveness.

  even if they worked better than placebos in the control group she concluded that the effectiveness was mainly modest.

  THEREFORE, it suggests that brain chemistry alone cannot account for the treatment of all cases
• strength : uses scientific methods


  the biological approach makes use of highly precise and objective methods such as scanning techniques.

  THEREFORE, it is based on objective and reliable data
• limitation: determinist


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