Biological approach

• the influence of genes, biological structures and neurochemistry on behaviour. Genotype and phenotype, genetic basis of behaviour, evolution and behaviour
• The biological approach views behaviour as being influenced by physical, physiological processes such as genetics, hormones, neurotransmitters and the structure of the brain.
• Each individual is born with 23 pairs of chromosomes, which have been inherited from their birth parents. 
• These are our genotype and form the basis for our development.   The biological approach suggests that this genetic makeup may be the basis for certain behaviours.  Genes carry the instructions for a particular characteristic (such as intelligence), but if, and how, this characteristic develops is a result of how this gene interacts with other genes and the influence of the environment.  Not all genes are ‘turned on’ and whether they are or not can be influenced by the environment
• Twin studies are used to determine the likelihood that certain traits have a genetic basis by comparing the concordance rates between a pair of twins.  The concordance rate is the extent to which both twins share the same characteristic.  If identical (monozygotic) twins are found to have a higher concordance rate than non-identical (dizygotic) twins it would suggest a genetic basis.  This is because MZ share 100% of their genes, whilst DZ share only 50% (the same as any siblings).  For example, Miguel et al (2005) found a 53-87% concordance rate for MZ twins and 22-47% for DZ twins for OCD
• Genotype

  • Each cell contains an identical set of genes; these are the genotype.  This is determined at fertilisation by the combination of genes that are contributed by the parents and it remains constant throughout life.  The genotype influences our development BUT events in our body are also dependent on the external environment. 
• Phenotype

  • From conception, genes begin to interact with the environment, initially this is the internal environment (the fluid within each cell and in adjacent cells).  Maternal exposure to toxins (e.g. drugs) and disease influence the internal environment.  After the child is born the external environment also interacts with the genotype.  The characteristics that are expressed as a result of these interactions are the phenotype.  Features of the phenotype change because of experience.
• ·       Hormones e.g. testosterone. The presence of hormones in the bloody causes physiological reactions from cells which lead to a specific behavioural reaction. For example, research has found that male athletes who were taking steroids (which cause an overproduction of testosterone) were significantly more aggressive.
• ·       Neurotransmitters e.g. dopamine and serotonin. Dopamine is an excitatory neurotransmitter, meaning that it encourages activity in the neuron it transmits to. It is associated with motivation. Serotonin is an inhibitory neurotransmitter, meaning that it prevents activity in the neuron it transmits to in order to calm the brain and balance mood. Adequate amounts of serotonin are necessary to maintain a stable mood. Research has found that when serotonin levels are low, people tend to display increased aggression and depression.

   
• Evolution is the changes in inherited characteristics in a biological population over successive generations.  The mechanisms behind biological evolution are natural and sexual selection.
• What is one way individuals within a species differ from each other?

  In terms of their physical characteristics and behavior
• Why do individuals within a species compete with each other?

  To gain access to resources such as mates and food
• How do advantageous behaviors affect survival and reproduction?

  They increase the likelihood of survival and reproductive success
• What is sexual selection in the context of competition for resources?

  It refers to the traits that are desirable to a mate
• What happens to advantageous behaviors over successive generations?

  • They are passed on to offspring
  • They become widespread in the population
  • Non-advantageous behaviors tend to die out
• What is an example of a behavior that may be passed on through natural selection?

  Aggressive behavior and mate retention strategies
• Why might males use mate retention strategies?

  To prevent their partners from infidelity and ensure their genes are in the offspring
• What are the key concepts related to natural selection and behavior in a species?

  • Variation in physical characteristics and behavior
  • Competition for resources
  • Survival of individuals with advantageous behaviors
  • Reproductive success linked to desirable traits
  • Transmission of advantageous behaviors to offspring
• Neurochemistry refers to the neurotransmitters that pass across the synapse. Neurotransmitters can be excitatory or inhibitory (excitatory ones trigger a nerve impulse).  Neurotransmitters are involved in several different behaviours
• Serotonin = OCD, aggression
• Dopamine = OCD, schizophrenia
• strengths of biological approach

  • There is research to support that there is a biological influence on behaviour.  For example, Tukel et al., (2013) found one form of the COMT gene to be more common in OCD patients than people without the disorder.  Iversen (1979) reported that post-mortems on schizophrenics revealed excess dopamine in the limbic system, suggesting that the neurotransmitter is involved in the disorder.   This evidence suggests that various biological factors (genes and neurochemistry) are involved in a wide variety of behaviour.
• Why is it difficult to establish cause and effect in biological research related to behavior?

  Because individuals are studied after developing maladaptive behaviors.
• What is a strength of the biological approach in psychology?

  It provides insights into the biological factors influencing behavior.
• How might the brain's plasticity affect research conclusions in the biological approach?

  The brain's plasticity means that environmental factors can influence behavior.
• What is more likely to cause behaviors according to the biological approach?

  Behaviors are likely a result of an interaction between genetics and the environment.
• How should the biological approach be considered in relation to other psychological approaches?

  • It should be considered alongside environmental influences.
  • The learning approach is an example of an environmental influence.
• What is a strength of the biological approach in psychology?

  Practical applications
• How do medications based on the biological approach treat abnormalities?

  They affect certain neurotransmitters
• What is the function of SSRIs in treating conditions like OCD?

  They increase the amount of serotonin that stays in the synapse
• What do antipsychotic drugs do in the treatment of schizophrenia?

  They bind to the D2 dopamine receptor, preventing neurotransmitter binding
• What did Leucht et al (2012) find regarding antipsychotics?

  They lead to a lower relapse rate of schizophrenia compared to a placebo
• What does the effectiveness of medication in treating disorders suggest about neurotransmitters?

  It suggests that neurotransmitters must play a role in these disorders
• What is a limitation of the biological approach in psychology?

  It is biologically reductionist.
• Why is the biological approach considered reductionist?

  Because it reduces complex behaviors to their smallest biological components.
• How does the biological approach explain complex behaviors like OCD and schizophrenia?

  By focusing on neurotransmitters like serotonin and dopamine.
• What is a significant issue with reducing human behavior to biological components?

  It overlooks the complexity of human individuals influenced by multiple factors.
• What is needed to understand the true cause of behavior according to the limitations of the biological approach?

  • A holistic approach
  • Consideration of other causes
  • Role of the unconscious (psychodynamic approach)
  • Role of conscious thought processing (cognitive approach)
• What is a limitation of the biological approach in psychology?

  It is biologically reductionist.
• Why is the biological approach considered reductionist?

  Because it reduces complex behaviors to their smallest biological components.