Biological Approach

• The biological approach assumptions

  - Emphasises importance of physical processes in the body such as genetic inheritance

  - Suggests that everything psychological is at first biological so to understand human behaviour, must look at biological structures first - genes/ neurochemistry/ nervous system
• The neurochemical basis of behaviour


  - Refers to the action of chemicals in the brain (neural=brain)

  - Much of thoughts and behaviours rely of chemical transmission in the brain

  - Occurs using Neurotransmitters.

  -An imbalance of neurotransmitters is a possible cause of mental illness.
• Neurotransmitters


  Chemicals that transmit information from one neuron to another

  
• Serotonin


  Affects mood, hunger, sleep, and arousal
• Dopamine


  A neurotransmitter associated with movement, attention and learning and the brain's pleasure and reward system.
• The genetic basis of behaviour


  - Behaviour geneticists study whether behavioural characteristics such as intelligence, personality, mental disorder etc. are inherited in the same way as physical characteristics such as height and eye colour.

  
  

  - Twin studies + concordance rates.
• Concordance rates


  Likelihood that both twins exhibit the same trait
• Monozygotic


  Identical twins

  
• Dizygotic


  Fraternal twins

  
• Genotype


  An organism's genetic makeup, or allele combinations.
• Phenotype


  An organism's physical appearance, or visible traits.

  
• Nature


  The influence of our inherited characteristics on our personality, physical growth, intellectual growth, and social interactions.
• Nurture


  Environment
• Evolution and behaviour


  Charles Darwin proposed the theory of natural selection - genetically determined behaviour that enhances an individual's survival will continue in future generations.
• Evolution


  Change over time

  
• Natural selection


  A process in which individuals that have certain inherited traits tend to survive and reproduce at higher rates than other individuals because of those traits.
• Strengths of the biological approach

  Real-world application

  - Promoted the treatment of clinical depression using antidepressant drugs that increase levels of the neurotransmitter serotonin at synapses in the brain.

  - HOWEVER, Cipriani et al (2018) found that although most of the drugs were more affective than placebos in comparative trials, they concluded that the effects of antidepressants were 'mainly modest'.

  
  

  Scientific methods

  - Used scanning techniques, such as fMRIs and EEGs.
• Limitations of the biological approach

  Biological determinism

  - Too simplistic and ignores mediating effect of the environment.