the biological approach

• the biological approach: the genetic basis of behaviour (twin studies)

  Behaviour geneticists study the extent to which behavioural characteristics, such as intelligence, personality, and mental disorders, are inherited. Twin studies are used to determine the likelihood that certain traits have a genetic basis by comparing the concordance rates between pairs of twins. If monozygotic twins are found to have higher concordance rates than dizygotic twins, it would suggest a genetic basis as MZ twins share 100% of genetic makeup.
• the biological approach: what are genotypes and phenotypes?

  A genotype is the genetic constitution of an individual organism. A phenotype is the was that genes are expressed through physical, behavioural, and psychological characteristics. The expression of a phenotype is inevitably influenced by environmental factors.
• the biological approach: the human nervous system

  The human nervous system is comprised of the brain and spinal cord. The structure and function of the brain including localisation of brain functions and subsequent behaviours. Specific locations of the brain are responsible for specific functions EG: Broca's area= speech production Wernicke's area= speech comprehension
• what is the Broca's area responsible for?

  speech production
• what is the Wernicke's area responsible for?

  speech comprehension
• the biological approach: influence of neurochemistry on behaviour

  Neurotransmitters such as serotonin can regulate mood and affect behaviour, such as leading the expression of depression in those with low levels of serotonin.
• the biological approach: Evolution and the importance of natural selection

  The main principle of evolutionary theory is that any genetically determined behaviour that enhances an individual's survival will continue in future generations (natural selection). The selection occurs because some traits give the possessor certain advantages. The possessor is more likely to survive, reproduce and pass on these traits. This principle can help explain how certain behaviours have developed – e.g. Bowlby’s monotropic theory which explains how humans may have evolved to seek (infant) and establish (mother) secure early attachments.
• the biological approach: Scientific methods of investigation

  The biological approach makes use of a range of precise and highly scientific methods. These include scanning techniques (MRIs), family and twin studies, and drug trials. With advances in technology, it is possible to accurately measure biological/neural processes in ways that are not open to bias. This means that the biological approach is based on reliable data and is scientifically strong.
• evaluation (AO3) biological approach: what are the 3 evaluation points regarding the biological approach?

  1. Real-life application
  2. Deterministic
  3. Biological methodology
• evaluation (AO3) biological approach: Real-life application

  Increased understanding of biochemical processes in the brain has led to the development of drugs such as Sertraline which is an SSRI that treats conditions such as depression. This is a strength of the biological approach because it means that sufferers are able to manage their condition and live a relatively normal life. However, as studies indicate they are effective in approximately 60% of people as found by Zohar, the biological approach cannot be the sole explanation for all disorders and therefore there may be an environmental or cognitive influence on the individual, questioning the reductionist nature of the biological approach as a comprehensive model for explaining all individuals’ behaviours.
• evalutation (AO3) biological approach: Deterministic

  The biological perspective is deterministic in the sense that it sees human behaviour as governed by internal, biological causes over which we have no control. This has implications for the legal system and wider society. One of the rules of law is that offenders are seen as legally and morally responsible for their actions. The discovery of a 'criminal gene', if there was such a thing, may complicate this principle - this as a defence in court and have implications for society and the legal system.
• evaluation (AO3) biological approach: Biological methodology

  The biological approach uses the rigorous experimental method, to yield objective and empirical data to investigate the biological basis of behaviour. This is evidenced through the research of Petersen who analysed MRi scans to find that the Broca’s area was active during a reading task. However, we must be cautious when applying the experimental method to all forms of human behaviour, as the influence of societal norms, the presence of others and our schemas may have an influence on our behaviour, questioning the comprehensiveness of the biological approach as an explanation for all human behaviour.
• AO1 summary of the biological approach for 16 markers

  The biological approach explains behaviour through biological structures and processes such as genes, hormones, brain activity and neurotransmitters. For example, it suggests that mental illnesses such as depression are caused by low levels of serotonin, a neurotransmitter involved in mood regulation. Brain imaging scans (such as fMRI) have allowed researchers to identify specific brain areas linked to functions, such as Broca’s area for speech production. The approach also uses twin studies to investigate the heritability of traits. Higher concordance rates in monozygotic twins (who share 100% of their genes) compared to dizygotic twins suggest a genetic basis for behaviour.