Biological Approach Flashcards
State the three assumptions of the biological approach
- Can only fully understand behaviour if we look to biological structures and processes within the body
- Our genes, neurochemistry and nervous system are the basis of any psychological process/behaviour
- Human behaviour is genetically determined through the process of evolution and natural selection
Genotype vs phenotype
Genotype is an individual’s genetic make-up. Phenotype is the behavioural and physical characteristics that occur as a result of our genotype interacting with the environment.
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/disorder than DZ twins, it suggests a genetic component
• This is thought to be because the only difference between the two pairs of twins is how genetically similar they are
2 examples of how our genotype can interact with the environment
PKU - A rare disease which if left unchecked can cause learning difficulties but if detected early enough can be controlled through diet.
How active someone is can cause fluctuations in their weight.
State four biological factors which influence behaviour
- Genes
- Neurochemistry
- Nervous system
- Evolution
What is evolution?
The gradual change in characteristics and behaviours of organisms due to the passing down of genes which provide them with an adaptive advantage
Example of genes influencing our behaviour
Genes which create vulnerability for OCD
1. Allele of the COMT gene - Produces less COMT. COMT regulates dopamine.
2. SERT gene - SERT gene affects the transport of serotonin, causing a decrease in serotonin levels
What is an example showing the influence of neurotransmitters on our behaviour?
Schizophrenia:
Hyperdopaminergia - Excessive levels of dopamine in the sub cortex and Broca’s area leading to positive symptoms
Hypodopaminergia - Low levels of dopamine in the prefrontal cortex leading to negative symptoms
Give two examples of the influence of the nervous system on our behaviour
Damage to Broca’s area – Broca’s aphasia - inability to produce fluent speech
Damage to Wernicke’s area - Wernicke’s aphasia - impaired language comprehension
Explain how aggression has become more widespread due to evolution
Aggression has evolved because it solved challenges faced by our distant ancestors, which in turn increased survival and reproductive success, and so became more widespread in the gene pool, through the process of natural selection
2 Strengths of the biological approach
Scientific methods of investigation:
The biological approach adopts scientific methodology in order to investigate the biological basis of behaviour. The results gained are therefore highly objective as they are based on biological findings, not subjective reporting and observations.
Real-life application. SSRI’s inhibit the re-absorption of serotonin in the pre-synaptic neuron, increasing the concentration of serotonin at the synapse. This increase in serotonin reduces anxiety and thus obsessive/irrational thoughts.
2 Limitations (1 Counter) of the biological approach
Lack of causal conclusions:
For instance, it could be argued that neurochemical imbalances, such as low serotonin in a depressed individual, is the consequence rather than the cause of their depression. The negative and faulty cognition associated with depression caused the low levels of serotonin observed, not the other way around.
Deterministic view of behaviour.
Sees human behaviour as governed by internal, biological causes over which we have no control. Implications for legal system – if there is a discovery of say a ‘criminal gene’ this suggests that criminals do not have control over their behaviour, which may complicate the principles of law that states offenders are legally and morally responsible for their actions.
Stephen Mobley was a murderer on death row in America. His attorney argues he was born to kill (biological determinism). His family history revealed 4 generations of violent crime including rape and murder. Appeal thrown out by judge. May be punishing people nit responsible for their own behaviour. COUNTER - if individuals discover they have a genetic predisposition for criminality this gives them the opportunity to avoid environmental situations likely to trigger this predisposition
