Biological Approach

Question 1

What are the main assumptions of the biological approach?

A01

Answer 1

• Everything psychological has a biological basis
• Our biology is determined by evolution and genetics
• To investigate our mind, we must investigate our brain

Question 2

What are and is the significance of genes?

AO1

Answer 2

Genes = section of DNA with genetic code for making enzymes and hormones
Allele = different forms of the same gene

• Genes control the development of characteristics and contain code for the production/functioning of CNS structures
• Since behaviour is determined by adequate functioning of the CNS and neurotransmitters, genes have an indirect impact on behaviour
• Problems with genes leads to problems with structure and functioning of the CNS thus affecting behaviour
• e.g. faulty 5HTT gene leads to issues with seratonin transportation thus resulting in lower levels of seratonin in the synapse which may lead to the development of OCD

Question 3

What is the significance of the brain?

AO1 (CAN PICK BETWEEN THIS AND NEUROTRANSMITTERS TO WRITE ABOUT)

Answer 3

• Controls our day to day behaviour and is responsible for the production of our thoughts, emotions, and sensations
• e.g. the cerebral cortex is responsible for high order functions such as thought and image
• brain damage affects our thinking pattern thus resulting in changes in behaviour

Question 4

What are and is the significance of neurotransmitters?

AO1 (Can choose between this and the brain to write about in 12 marker)

Answer 4

• Brain is full of neurons which communicate through electrical impulses and chemicals
• Neurotransmitters = chemical messengers that travel back and forth in the synapse delivering messages between neurons
• Neurotransmitters travel across the synapse to pass on info to the next neuron
• There are different types of neurotransmitter: excitatory will increase chance that the neuron will fire whereas inhibitory will decrease the likelihood that a neuron will fire
• e.g. dopamine = excitatory, associated with motivation and drive
• e.g. seratonin = inhibitory, adequate amounts necessary for mood stabilisation
• Problems with levels of neurotransmitters leads to issues in the brain resulting in abnormal behaviour
• e.g. low seratonin is associated with depression, high levels = mania and anxiety

Question 5

What is the significance of evolution?

AO1

Answer 5

1. A random mutation occurs
2. This mutation leads to adaptive characteristics e.g. aggression
3. Those with that characteristics are better suited to survive
4. Natural selection occurs as those who don’t have the characteristic fail to compete with those who do have the mutation
5. The survivors live to reproduce and pass on this adaptive trait that helped them survive
6. This process continues for each successive generation until the entire species has this characteristic thus affecting our behaviour today

Question 6

How does McGuffin support the biological approach?

Answer 6

• A strength of the biological approach is that there is supporting evidence from twin studies
• For example, McGuffin conducted a twin study on depression and found concordance rates of 46% for MZ twins and 20% for DZ twins
• This suggets that depression is at least partly genetic because as the proportion of shared genes increases when comparing DZ twins (50%) to MZ twins (100%) so does the chance of both twins demonstrating depression
• As the evidence suggests that genes influence our behaviour, this supports the BA which also suggests that psychological traits are determined by biological factors
• This validates the BA

Question 7

How is practical applications a strengh?

DON’T USE IF DIDN’T TALK ABOUT NEUROTRANSMITTERS IN A01

Answer 7

• One strength is that the understanding of the impact of neurotransmittes on brain functioning has led to the development of drugs which alter levels of neurotransmitters in the brain
• For example, knowing that low levels of seratonin leads to depression has lead to antidepressants like SSRIs which increase levels of seratonin in the brain to alleviate symptoms of depression. Thus it can improve lives
• Also Gilton found that antidepressants are effective in 65-75% of cases
• As the treatment is effective and based on the underlying assumptions of the BA we can assume the BA is also valid

Question 8

How are twin studies a weakness?

Answer 8

• A weakness of BA is that the evidence it relies on (twin studies) have questionable validity
• Twin studis assume MZ twins have a higher concordance rate than DZ twins as they have a high proportion of genes (MZ=100%, DZ=50%). In doing so, the BA fails to account for the role of the environment; MZ rwins are more likely to be treated the same by their environment as they look the same (identical)
• Therefore, the higher MZ concordance rate may not be due to a higher proportion of shared genes but rather the same treatment from the environment
• Since we can’t be certain it is difficult to disentangle the roles of nature and nurture in behaviour. This leads us to to question the valifity of twin study conclusions
• As a result also decreases the validity of the BA

Question 9

How is reductionism a weakness?

Answer 9

• A weakness is that the BA is redutionist. This is because it oversimplifies complex behaviours (such as thought and mental abnormality) down to physical factors such as genes and neurotransmitters
• In doing so, it ignores the role of factors such as environment.
• The diathesis stress model suggests that genes only make an individual more vulnerable to developing an illness or behaviour, however, certain environmental triggers e.g. traumatic event may also be required in order for the behaviour to be expressed
• This shows that BA by itself doesn’t account for the interaction od different factors. To better understand behaviour, psychologists should take a holistic approach and consider all factors such as genes and environment
• Since the BA doesn’t do this, it can be considered reductionist thus reducing its validity