4.2.1 The Biological Approach

Question 1

What is the biological approach?

Answer 1

The biological approach is a perspective that emphasises the importance of biological and physical structures and processes, to fully understand human behaviour.

Question 2

When, and how, did the biological approach emerge?

Answer 2

The notion that human behaviour has a biological and evolutionary origin predates the emergence of psychology.
It stemmed from the work of Charles Darwin in the mid-1800s.

Question 3

What are the key assumptions of the biological approach?

Answer 3

Everything psychological is at first biological, so all behaviours have a physical basis (as the mind is in the brain).
We must look at biological structures and processes in the body to understand human behaviour.
A reductionist approach, as to understand psychological functioning, we must analyse these functions in terms of even smaller units of analysis (eg. Neurones)
Behaviour is strongly influenced by our genetic makeup-up and inheritance.
The CNS is essential for thought and behaviour: as understanding brain structures and functions can explain both behaviour and thought.
Chemical processes in the brain are responsible for psychological functioning: an imbalance of these can lead to mental disorders.
Humans have evolved through Darwinian evolution, and have much in common with those close to us on the evolutionary tree.
Evolution has taken place over millions of years, and the fight or flight response is common across all of the animal kingdom.
Scientific methods should be used to study behaviour (PET scans, twin studies and experiments)

Question 4

What are genes?

Answer 4

Genes make up chromosomes, and consist of DNA that codes for the physical and psychological features of an organism. They are inherited from parent to offspring.

Question 5

What do biological psychologists believe about genes?

Answer 5

Biological explanations of behaviour often focus on genes. They believe that genes are responsible for our psychological features as well as physical features.

Question 6

What is a genotype?

Answer 6

Genotype refers to the set of genes that an individual possesses

Question 7

What is a phenotype?

Answer 7

Phenotype refers to the characteristics of an individual, determined by both genes and the environment.

Question 8

What do biological psychologists believe about genotypes and phenotypes?

Answer 8

Biological psychologists believe that much of human behaviour is determined by an interaction between inherited factors (nature) and the environment (nurture).

Question 9

What are monozygotic twins?

Answer 9

MZ twins share the same genotype, so are 100% identical twins.

Question 10

What are dizygotic twins?

Answer 10

DZ twins share 50% of the same genes, so are not identical.

Question 11

What are twin studies and how are they used?

Answer 11

A genetic test is able to reveal a genotype, but not a phenotype, which shows the importance of the environment.
Twin studies are used to investigate whether certain psychological characteristics have a genetic basis.
-this is achieved by analysing concordance rates (the extent to which the twins share the same characteristics)
-if the characteristic is genetic, it will be the same in MZ twins but different in DZ twins.

Question 12

How can PKU be applied to genotypes and phenotypes?

Answer 12

PKU disease is a genetic disorder that will develop if left untreated. If detected early, this phenotype is less likely to develop due to changes made in the environment (restricted diet).

Question 13

What did McGuffin et al’s twin study show?

Answer 13

The concordance rates of major depression for MZ twins was 46%, but only 20% for DZ twins. This supports the idea that there is a genetic basis for many psychological disorders.

Question 14

What do biological psychologists believe about biological structures?

Answer 14

Biological psychologists believe that the structure of organs, such as the brain, the CNS, PNS and endocrine system, determine our behaviour.

Question 15

Describe how the endocrine system can influence our behaviour?

Answer 15

The endocrine system is a body-wide system of glands, which secrete chemical messages known as hormones.
For example, during the fight or flight response, the adrenal glands secrete adrenaline which causes physical changes to enhance attention and strength.
Hormones can have a short or long term effect on the body and behaviour.
For example, oestrogen and testosterone play a role in the development of gender-specific physical features.

Question 16

What is the brain?

Answer 16

An organ that is part of the CNS, and the centre of all conscious and unconscious thought.

Question 17

What is localisation of function?

Answer 17

Localisation of function is the idea that specific brain areas are responsible for certain functions.

Question 18

What is the role of the brain stem?

Answer 18

To control core functions including heart rate and breathing

Question 19

What is the role of the cerebellum?

Answer 19

To control muscle movements and balance

Question 20

What is the role of the occipital lobe?

Answer 20

Visual perception

Question 21

What is the role of the temporal lobe?

Answer 21

To process auditory information

Question 22

What is the role of the parietal lobe?

Answer 22

To process sensory information

Question 23

What is the role of the frontal lobe?

Answer 23

Rational decision making and higher order functions

Question 24

What is the limbic system?

Answer 24

The emotional centre of the brain

Question 25

How was research conducted to link brain structure to behaviour?

Answer 25

The research that identified the influence of brain structures on behaviour were case studies of unusual individuals. This allows inactivity or damage of regions of the brain to be associated with particular behaviours. This confirms the role of brain structures in the performance of behaviours.

Question 26

Explain the role of the nervous system in behaviour?

Answer 26

The nervous system and neuronal activity also control human behaviour.
For example, eating (feeling hungry and full) is controlled by the activity of neurones.
This is done via electrical and chemical messages that travel through the body.

Question 27

Explain how neurotransmitters determine behaviour?

Answer 27

Biological psychologists recognise the role of neurotransmitters in determining behaviour, when they are released at the synapse to send signals between neurones.
An imbalance of neurotransmitters cans be associated with atypical behaviour eg. Too little seretonin is associated with depression, so SSRI’s are used to treat this.

Question 28

What other chemicals influence behaviour in the body?

Answer 28

Hormones- chemical messages secreted by glands

Question 29

Who developed the theory of evolution by natural selection?

Answer 29

Charles Darwin

Question 30

What is the theory of natural selection?

Answer 30

Natural selection ensures that adaptive characteristics are passed onto future generations: it argues organisms with traits that enhance survival and reproduction are more likely to pass these advantageous characteristics to their offspring.
Some characteristics are adaptive and some are maladaptive, and overtime, the adaptive traits become more common in the population.

Question 31

What is evolution?

Answer 31

Evolution is the gradual change in inherited characteristics over many generations.

Question 32

How is evolution applied to psychology?

Answer 32

Darwin influenced the development of evolutionary psychology and psychologists try to explain behaviour in therms of how people adapt to a constantly changing environment. They claim that genes account for psychological characteristics.

Question 33

How can evolution be applied to aggression?

Answer 33

Species defend their territory to protect families and resources.
Humans show this by being territorial and going to war, as it is an inherited characteristic.