THE Biological Approach

• The biological approach assumes everything psychological has a biological basis
• Alleles are different forms of the same gene. Genes are a section of DNA that code for the sequence of amino acids in a protein which makes enzymes and hormones. They control the development of characteristics and contain code for the production/functioning of CNS structures like the Brain and spinal cord. Since behaviour is determined by the adequate functioning of the CNS/NTs, genes have an indirect impact on behaviour
• If there is a problem with genes it can lead to problems with the structure/function of the CNS. This will lead to problems with behaviour. Researchers found that genes have led to a vulnerability for OCD e.g. a faulty 5HTT gene can led to issues with the transportation of serotonin which causes lower levels of serotonin in the synapse resulting in OCD
• The Brain controls our day to day behaviour and is responsible for the production of our thoughts, emotions and sensations e.g. the cerebral cortex controls higher order functions such as thought and language. When the brain suffers damage it leads to changes in our behaviour as it affects our thinking pattern
• The brain is full of neurons which communicate through electrical impulses and chemicals. NTs are chemical messengers that travel back and fourth in the synapse, delivering messages between neurons. NTs travel across the gap between two neurons and pass on information to the next neuron.
• Different types of NTs increase the likelihood that a neuron will fire and others reduce this. Dopamine is excitatory NT that increases the likelihood that a neuron will fire. Dopamine is associated with drive/motivation. Serotonin is an inhibitory NT that decreases the likelihood that a neuron will fire. Serotonin is associated with mood stabilisation. Researchers have found that low levels of serotonin have been linked to depression and high levels of dopamine are associated with anxiety
• Evolution

  • Random mutation
  • Adaptive characteristics
  • Better suited to survive
  • Natural selection
  • Genetically pass on traits which helped you survive
  • Carried this on for each successive generation
  • Evolve - affects beh today
• Strength of genetic explanations of human behaviour is the supporting evidence from twins studies. McGuffin conducted a twin study on depression and found concordance rates of 46% for MZ twins and 20% for DZ twins. As the proportion of shared genes increases when comparing DZ 50% to MZ 100%, we find that the likelihood of both twins sharing the trait of depression also increases....
• (Strength - Supporting evidence from twin studies) This is a strength because it suggests that depression is at least partly genetic since twins who are genetically identical are twice as likely to both have the disorder than non-identical twins. As the evidence supports the idea that psychological characteristics are determined by our biology. This increases the validity of the biological approach.
• S - practical app of biochemical explanations. Our understanding of the impact of NT on brain functioning and beh lead to the development of drugs which alter levels of NTs in the brain. E.g. knowing low levels of serotonin leads to depression, led to the development of antidepressants like SSRIs which increase levels of serotonin in the brain which may alleviate symptoms of depression. Shows that assumptions of BA can improve lives. Increase V