Biological approach

• Assumptions

  • Everything psychological is at first biological
  • to fully understand human behaviour we must look at biological structures and processes within the body e.g genes, neural chemistry and the nervous system
  • an understanding of the brains structures and functions can explain our thoughts and behaviour
  • the mind lives in the brain which means that all thoughts, feelings and behaviours have a physical basis
• Define genotype

  The genetic makeup of an individual
• Define phenotype

  The observable characteristics of an individual which are a consequence of the environment and their genotypes
• Define evolution

  Evolution is the process whereby useful features are introduced into a species so that they can adapt to their environment

  Species adapt to survive and reproduce more effectively
• Define natural selection

  Natural selection refers to characteristics which help an organism to survive long enough to be able to reproduce

  These genes are then passed onto offspring to give them an advantage for survival
• Explain how neurochemistry/hormones affect behaviour

  • Neurotransmitters are chemicals that transmit messages between neurons
  • different levels of neurotransmitters can affect mood and behaviour
  • e.g there are excitatory and inhibitory neurotransmitters
• Define excitatory neurotransmitters

  • Excitatory neurotransmitters trigger an impulse
  • e.g dopamine - associated with motivation
• Define inhibitory neurotransmitters

  • Inhibitory transmitters stop an impulse
  • e.g serotonin - associated with mood
• Define monozygotic twins

  Identical twins
• Define dizygotic twins

  Non identical twins
• Explain how twin studies work

  • Twin studies determine the likelihood that certain traits have a genetic basis by comparing concordance rates between pairs of twins (the extent to which they share the same characteristics)
  • if monozygotic twins are found to have a higher concordance rate than dizygotic twins this would suggest a genetic basis
  • this is because monozygotic twins share 100% of each others genes where as dizygotic twins share about 50%
• What studies are used to determine the genetic basis of behaviour

  To determine whether behavioural characteristics (mental disorder, intelligence etc) are inherited in the same way that physical characteristics (eye colour, height etc) are twin studies are used
• Limitation - determinist view of behaviour

  • This is because biological psychologists see human behaviour as governed by internal, biological causes over which we have no control
  • therefore this approach could have possibly negative implication for wider society as criminals may be able to excuse their behaviour
• Strength - real life application

  • Led to the development of psychoactive drugs
  • these treat serious mental illnesses, such as depression
  • therefore sufferers are able to manage their condition and live a relatively normal life
• Strength - scientific methods of investigation

  • The biological approach includes a range of highly scientific methods to study human behaviour
  • e.g scanning techniques such as fMRIs and EEGs
  • therefore it is possible to accurately measure biological and neural processes in ways that are less open to bias