Biological Approach Flashcards
Biological approach
The biological approach in psychology examines how genetics, brain structures, neurochemistry, and evolution shape behaviour. It focuses on the role of hormones, neurotransmitters, and inherited traits in influencing thoughts and emotions.
The biological approach assumes:
Biological approach main components:
- Genetics - The Genetic Basis of Behaviour
- Behaviour geneticists study whether behavioural characteristics, e.g., intelligence, personality and mental disorders are inherited in the same way as physical characteristics e.g., height and eye colour.
- Twin studies are used to determine the likelihood that certain traits have a genetic basis by comparing the concordance rates between sets of twins; that is, the extent to which both twins share the same characteristic.
- If monozygotic twins are found to have higher concordance rates than dizygotic twins, e.g., for musical ability, schizophrenia, etc.. this would suggest a genetic basis. This is because monozygotic twins share 100% of each other’s genes, whilst dizygotic twins share about 50% (same as any siblings).
- Recent research has found that monozygotic twins have an increased concordance rate of developing schizophrenia, compared to dizygotic twins.
- Other psychological conditions are also influenced by genes. For example, McGuffin et al. found that if one identical twin has depression, there is a 46% chance that the other twin will also have depression.
- This suggests that there is a genetic component to illnesses like schizophrenia and depression. These relationships are important for understanding the genetic component of psychological illnesses and demonstrate the impact of genes on certain human conditions.
- Genetics - Genotype and Phenotype
- Genotype refers to a person’s genetic make-up, whereas phenotype is the way that genes are expressed through physical, behavioural and psychological characteristics.
- The expression of a genotype is inevitably influenced by environmental factors. For instance, identical adult twins usually look slightly different because one has exercised more or one has dyed their hair. So, despite having the same genes, they way they are expressed (the phenotype) is slightly different.
- A practical example of the difference between genotype and phenotype is PKU, which is a genetic disorder that affects the ability to break down a substance contained in normal foods.
- If the individual follows a strict diet avoiding this substance, their phenotype will be normal for intelligence and behaviour, however if they eat a diet containing this substance, then it will accumulate in the brain, which will lead to a different phenotype - severe learning difficulties and behavioural problems.
- This shows that the presence of particular genes might lead to different outcomes depending on the social environment. This shows that characteristics depend upon an interaction between the genes and the environment.
- Evolution
- In the 19th century, Charles Darwin proposed the theory of natural selection. The main principle of this theory is that any genetically determined behaviour that enhances an individual’s chances of survival will continue in future generations, i.e. be naturally selected.
- In nature this selection takes place ‘naturally’ - no one ‘decides’, the selection occurs simply because some traits give the possessor certain advantages meaning they will be more likely to survive, reproduce and pass on these traits. If the individual does survive for a long period of time but does not reproduce, the traits do not get passed on into the gene pool.
- A classic example of evolutionary psychology research is Buss’s survey of heterosexual male selection. Across all 37 countries studied, he found that men preferred good looks, youth and chastity, whilst women preferred good financial prospects, industriousness and dependability. These results suggest that certain behaviours and traits have evolved in both males and females since they promote a better opportunity for passing on favourable genes.
- Neurochemistry & Brain physiology
- Biological psychologists also recognise the role of chemicals in determining behaviour. At the synapse, impulses are transmitted between neurons by chemicals called neurotransmitters, where they inhibit or excite the receptive neuron to achieve different responses. Imbalances in the number of neurotransmitters are associated with atypical behaviour.
- Research in this area helps us to understand the role of neurotransmitters. For example, research by Crockett et al. suggests that abnormally low levels of serotonin are linked to aggressive behaviour indicating that this neurotransmitter is important in regulating behaviour and impulse control.
- Other types of chemicals found in the body which can also influence behaviour are called hormones. They are governed by the endocrine system and regulates the circulation of these hormones, which are released by glands into the bloodstream, where they travel to the target cells that are then activated.
- Carre et al., in a study investigating the behaviour of ice hockey players, found that high levels of testosterone are associated with defensiveness and territoriality.
- Interactions between regions of the brain help to control different functions, which biological psychologists assume to be significant in determining our actions. For instance, the frontal lobe is thought to be involved in behaviours such as control and attention.
Strength
Point: A strength of the biological approach is its reliance on the scientific method through the use of controlled experiments as a means of investigation.
Evidence: Experiments in this approach are conducted in highly controlled laboratory settings, allowing researchers to isolate variables and establish cause-and-effect relationships. This level of control ensures that studies can be replicated under the same conditions. Furthermore, while early brain research was heavily dependent on case studies, which were limited due to researcher bias and a lack of experimental control, advancements in neuroscientific techniques, such as fMRI and EEG/ERP scanning, have significantly improved the accuracy and objectivity of biological research.
Justification: This demonstrates that the biological approach benefits from objective, empirical evidence, reducing the influence of subjective interpretations made by other approaches, e.g., the cognitive approach. By utilising scientific techniques, researchers can investigate biological processes with a greater level of authenticity.
Implication: As a result, this amplifies the scientific robustness of the biological approach as it relies on rigorous methodology and technological advancements to draw out impactful theories whilst simultaneously reinforcing psychology as a distinct scientific discipline. Additionally, this approach has significant real-world applications, especially in fields such as medicine, neuroscience and mental health treatment.
Strength
Point: A key strength of the biological approach is its practical applications in improving people’s daily lives.
Evidence: Research into neurochemical imbalances in depression has led to the development of effective drug treatments, such as SSRIs, which help regulate neurotransmitter levels and alleviate symptoms. Additionally, studies on circadian rhythms have contributed to improving shift work conditions, helping to enhance productivity and reduce health risks associated with disrupted sleep patterns.
Justification: The success of these applications demonstrates that biological explanations have real-world applicability. The development of treatments based on biological research shows that the approach is not only theoretical but also practically effective in addressing psychological and physiological changes.
Implication: Consequently, this underscores the practical value of this approach, as it has directly contributed to medical advancements and workplace reforms that benefit individuals and society as a whole. By applying scientific research to real-world issues, it has helped enhance both individual well-being and societal functioning, demonstrating its effectiveness beyond theoretical study.
Weakness
The biological approach is reductionist. Reductionism is the belief that complex human behaviour can be explained by breaking it down into its smallest parts, such as the action of genes or hormones. For example, many explanations of mental illnesses are reductionist because genes or neurochemical imbalances are believed to be the main cause of these illnesses. However, whilst a reductionist approach lends itself to scientific investigation, critics argue that we cannot fully understand a behaviour without also taking into account other factors that influence it. These include cognitive, emotional and cultural factors. Therefore, it may not offer comprehensive, valid explanations of behaviour as it is too narrow in scope.
However, the reductionist nature of this approach may lend itself well to scientific investigations. This is because it allows researchers to establish a cause of behaviours such as mental illnesses, assisting in diagnosis and treatments.
Weakness
The biological approach takes a determinist stance. It argues that human behaviour is governed/controlled by internal, biological causes. Causes we have no control over. This has huge implications for the legal system and wider society. The law states that offenders are seen as legally and morally responsible for their actions. Recent research suggesting a genetic basis for criminal behaviour had led to concerns about how this information might be used. It creates the danger that genes might be used as a convenient explanation for complicated human behaviour like aggression negating responsibility and offering a defence in court.
