Biological approach

• Biological approach

  Assumes that our behaviour is determined by our genes, which are inherited from our parents
• Twin studies

  • Examine the concordance rate of monozygotic (identical) and dizygotic (non-identical) twins
  • Primary method of studying whether behaviour is inherited
• Any differences between individuals are often the result of genetic variation
• Concordance rate

  Percentage of twins that share the same trait, given that at least one twin has the trait
• Genotype


  A person's actual genetic makeup
• Phenotype


  The characteristic expressed when interacting with the environment
• Natural selection

  Theory proposed by Darwin that suggests genetically determined behaviours that enhance survival will continue in future generations
• Those who survive longer are more likely to reproduce and pass on their genetics to their offspring
• AO3

  One strength of the biological approach is that it has real-world practical applications. For example, it has led to the successful development of drug treatments such as antipsychotics to treat schizophrenia to reverse brain abnormalities. This means people who suffer from genetically inherited mental disorders such as OCD are able to be treated. Therefore, the biological approach has immense value in improving the quality of life for individuals through therapy in the real world
• AO3

  Another strength of the biological approach is its ability to study behaviour scientifically. For example, Maguire used MRI scans in order to measure the size of the hippocampus. This means the results provide empirical and objective data, limiting any chance of human error or bias. Therefore, the methods used in the biological approach enhances its scientific credibility in psychology.
• AO3

  One weakness of the biological approach is that it is biologically deterministic. For example, the approach suggests that behaviour is influenced by our genes and neurotransmitter activity in the brain. This implies that individuals may not have free will over their actions, potentially allowing criminals to use genetic factors as a defence in criminal cases. As a result, the deterministic nature of the approach has negative implications for assigning responsibility in the criminal justice system.
• What is the counter argument to biologically deterministic?

  However, this may be positive because if individuals discover they have a genetic predisposition for criminality, it gives them the opportunity to avoid environmental situations that are likely to trigger this predisposition or develop coping skills that would protect them from its influence.
• AO3

  Another weakness of the biological approach is that it is reductionist. For instance, it reduces complex behaviour, thoughts and emotions to low-level biological mechanisms like genes and nerve impulses. This means it fails to consider environmental factors such as social and cultural influences on behaviour. Therefore, the overly reductionist nature of the biological approach limits its explanatory power in understanding behaviour. 
• Give one example of how the genotype has interacted with the environment

  1. PKU= a rare genetic disorder, if left unchecked it can cause learning difficulties. If detected early enough can be controlled through diet
• Explain the difference between genotype and phenotype

  Genotype= an individual's genetic make-up whereas phenotype is the product of what happens once the genotype has interacted with the environment 
• State the three assumptions of the Biological approach

  1. Can only fully understand behaviour if we look to biological structures and processes within the body.
  2. Our genes, neurochemistry and nervous system are the basis of any psychological process/behaviour
  3. Human behaviour is genetically determined through the process of evolution and natural selection
• Explain the difference between MZ twins and DZ twins

  MZ- share 100% of their genes/DZ twins- share 50% of their genes
• Define concordance

  The presence of the same trait in both members of a pair of twins
• How do twin studies allow us to see the genetic influence on behaviour?

  If MZ twins show a higher likelihood of sharing behaviour/disorders than DZ twins- suggests a genetic component
• State 4 biological factors which influence behaviour

  1. Genes.
  2. Evolution
  3. Neurochemistry
  4. Nervous system
• What is an example showing the influence of neurotransmitters on our behaviour?

  Increased levels of dopamine leading to OCD
• Give 2 examples of the influence of the nervous system on our behaviour?

  1. Damage to the limbic system (emotional centre in brain)= increased aggression
  2. Damage to Broca’s area= inability to produce speech
• What is an example of a behaviour that could have become widespread due to evolution?

  One example of a behavior that could have become widespread due to evolution is aggression in our ancestry. Aggression, in terms of being more able to gather resources and protect the family, increased the likelihood of survival and reproduction. As a result, the genetics for aggression are passed on to future generations, leading to aggression becoming more widespread.