Approaches To Psychology: Biological Approach

Question 1

Where do genes come from and how do they influence behaviour

Answer 1

At conception, the egg and sperm join up to give a total of 46 chromosomes
Each chromosome is made up of a coil of DNA, which in turn is made up of lots of genes
The genes contain the information that make us unique in appearance (e.g. hair, skin and eye colour)
However, genes are also relevant in psychology, as they are important in the development of the brain, and therefore have a role in our behaviour

Question 2

What are the 3 assumptions of the biological approach

Answer 2

Human behaviour can be explained by looking at biological components such as hormones, genetics, evolution and the nervous system

In theory, if we can explain all behaviour using biological causes, unwanted behaviour could be modified or removed using biological treatments such as medication for mental illness

Experimental research conducted using animals can inform us about human behaviour and biological influences, because we share a lot of biological similarities

Question 3

How does Darwin’s theory of evolution explain certain behaviours

Answer 3

Darwin’s theory of evolution suggests that people with better genes are more likely to survive and reproduce and pass on their useful genes
Those who are less well adapted will be less likely to survive and reproduce and pass on their genes
Eventually, their less useful genes will be eliminated from the gene pool for that species

Early humans became better adapted to their environments through natural selection
This means behaviours such as phobias and aggression may have evolved because of the survival advantage they gave

Question 4

Difference between genotype and phenotype

Answer 4

The genotype of a person is the genes they have
The phenotype of a person is the characteristics their genes produce - e.g. hair and eye colour

Question 5

How can genetics explain psychological traits

Answer 5

Faulty genes are known to cause some diseases that have psychological effects, e.g. Huntington’s disease that leads to a deterioration of mental abilities
Biological psychologists reckon that genetics can explain “psychological traits”
These are things like gender behaviour (things that men and women do differently), intelligence, personality and sexual orientation

Question 6

Why do psychologists study genetics and what methods do they use

Answer 6

They study genetics to see which genes make some people more likely to develop things like mental illness or addictions
Twin studies and adoption studies are useful for studying these areas

Question 7

How can twin studies be used to study mental illnesses

Answer 7

Identical twins share 100% of their genes
So in theory, if illnesses such as schizophrenia has a purely genetic basis and if one twin suffers from schizophrenia, then the other twin will too
Non-identical twins share 50% of their genes, so the risk of both suffering should be lower

Question 8

Method of Gottesman’s meta-analysis of twin studies

Answer 8

Gottesman carried out a meta-analysis of approx 40 twin studies

Question 9

Results of Gottesman’s meta-analysis of twin studies

Answer 9

It was found that having an identical twin with schizophrenia gave you a 48% chance of developing the condition
This reduced to 17% in non-identical twins

Question 10

Conclusion of Gottesman’s meta-analysis of twin studies

Answer 10

Schizophrenia has a strong genetic basis

Question 11

Evaluation of Gottesman’s meta-analysis of twin studies

Answer 11

The meta-analysis was carried out on field studies, giving the research high ecological validity
Because identical twins share 100% of their genes, it might be expected that both twins would always suffer from the same conditions
Both twins had developed schizophrenia in only about half of the cases means that another factor must be involved
Identical twins tend to be treated more similarly than non-identical twins and so the family environment might play a large role

Question 12

How can adoption studies be used to study mental illnesses

Answer 12

Adoption studies have provided evidence for a genetic basis of mental illnesses like schizophrenia

Question 13

Method of Heston’s adoption study of schizophrenia

Answer 13

47 adopted children whose biological mothers had schizophrenia were studied
Control group consisted of 50 adopted children whose biological mothers didn’t suffer from schizophrenia
Children were followed up as adults and were interviewed and given intelligence and personality tests

Question 14

Results of Heston’s adoption study of schizophrenia

Answer 14

Of the experimental group, 5 of the 47 schizophrenia, compared to 0 in the control group
Another 4 of the experimental group were classified as borderline schizophrenic by the raters

Question 15

Conclusion of Heston’s adoption study of schizophrenia

Answer 15

The study supports the view that schizophrenic has a genetic basis

Question 16

Evaluation of Heston’s adoption study of schizophrenia

Answer 16

Interview data can be unreliable and affected by social desirability bias
However, interviews are a good way of getting data in a naturalistic way
The adopted children whose mothers didn’t suffer from any conditions might have not shown any symptoms of schizophrenia yet - it can’t be completely ruled out

Question 17

What are PET scans

Answer 17

Stands for positron emission tomography
Shows which parts of the brain are active during different tasks
By studying PET scans, we can link certain areas of the brain with particular functions
They also allow us to see where the brain is most active when we are thinking about certain things

Question 18

What are CAT scans

Answer 18

CAT scans detect damaged parts of the brain, tumours and blood clots
Brain structure is shown, not function

Question 19

What are MRI scans

Answer 19

They can detect small tumours and provide detailed information about structure

Question 20

What are fMRI scans

Answer 20

Functional MRI scans provide structural and functional information

Question 21

What are SQUID magnetometry

Answer 21

They produce accurate images of brain activity by measuring the magnetic fields generated when neurons are active
However, outside sources of magnetism can affect measurements

Question 22

Positive evaluation of the strengths of the biological approach

Answer 22

It is a scientific approach. Highly scientific methods e.g. fMRIs, EEGs & twin studies lead to reliable data.

Helps establish psychology as a respectable science

Impact of biology on behaviour can lead to treatment and intervention to those suffering e.g. anti-depressants

Understanding how an abnormal brain works can shed light on normal brain functioning

Measurements can be objective and use of complex machinery allows accurate and precise measurements

Question 23

Negative evaluation of the limitations of biological approach ( what it regards humans as )

Answer 23

It is a deterministic approach as it believes that we are determined by our physiological, genetic or evolutionary make-up.
Thus stating that there is no free will.

Reductionist: all human behaviour can be explained through biological processes and we are not unique
It is also dehumanising to present humans as ‘biological machines’

Biological approach ignores the role of the environment etc. it should be used in combination which is known as the biosocial approach

Question 24

Negative evaluation of limitations of the biological approach ( how it is carried out )

Answer 24

Research may focus on rare conditions that have little impact on the everyday lives of most people

Complex machinery operated by humans and therefore measurements could be subject to human error

Correlations frequently employed – cannot determine cause and effect

Small or restricted samples make findings difficult to generalise

Laboratory experiments lack ecological validity

Question 25

How did psychologists study the brain before brain scans

Answer 25

They relied on case studies of people who had experienced brain injuries or had brain operations
If the person had brain damaged in a specific area and a change in behaviour then it’s assumed that the two were related

Question 26

Case study of Phineas Gage

Answer 26

Damage to frontal lobe after explosion causing an iron bar going through his head
After incident he was less organised and more impulsive, also became more aggressive
Lead to the belief that this area is responsible for these behaviours
However, this is a case study of only one person and so the results are not generalisable to everyone

Question 27

How do psychologists investigate the brain

Answer 27

Case studies on brain injuries are no conducted in controlled circumstances, less scientific
Also less ethical as we cannot purposefully inflict brain injuries on humans
Non - human animals have been used to study brain structure and behaviour
Differences between non - human and human brains means that the results may not be able to be applied to human behaviour
This is why psychologists use brain scans