The Biological Approach

Question 1

‘All that is psychological is first physiological’

Answer 1

• Nature, not nurture; all behaviour is innate
• Mental and physical procedures are linked and all behaviour comes from genetic make-up

Question 2

Assumptions of the biological approach

Answer 2

• This perspective emphasises the importance of physical processes in the body such as genetic inheritance, hormones, neurochemistry and the nervous system and their impacts on behaviour
• Everything psychological (behaviour and thought processes) has an innate biological cause - understanding brain structure and functions help to explain thoughts and behaviours
• Not a blank slate
• The mind and brain are the same thing (unlike cognitive)
• Genes affect behaviour and influence psychological differences between people
• We can use animal research to identify genetic traits and thus explain human behaviour

Question 3

Monozygotic Twins

Answer 3

Share 100% of their DNA and genes. Are a result of one fertilized egg splitting.

Question 4

Dizygotic Twins

Answer 4

Share around 50% of their DNA. Are a result of two separate fertilization’s in the same pregnancy

Question 5

Twin studies - investigating the biological approach

Answer 5

Allow us to assess whether a characteristic is genetic or environmental; both twins are studied to determine whether they share characteristics.
Concordance = a percentage that shows how many twin pairs shared a characteristic studied
As MZ twins share 100% of their genes and DZ share 50%, we would expect that if a characteristic is genetic the MZ concordance would be higher than the DZ. If a characteristic is completely genetic, the concordance of MZ twins should be 100%.
Twin studies have suggested that certain behaviours, such as intelligence, personality and mental illness are genetically determined.

Question 6

Twin studies pt2

Answer 6

However, these studies assume that both MZ and DZ pairings share the same environment - yet the environment may be more similar for MZ pairings compared to DZ twins. MZ twins will therefore be treated similarly by their parents and other people in comparison to DZ twins as they are identical. Findings could therefore be interpreted as supporting nurture rather than nature; consequently, twin studies may not strongly support the biological approach, as they suggest that some behaviour is genetic and some is not.

Question 7

Comparative method (animal studies) - investigating the biological approach

Answer 7

Animals are studied and conclusions are generalised to humans. Research has found that mice reared alone showed a tendency to attack other mice when first exposed to the, suggesting there is a biological basis for aggression as the mice could not have learned this aggression through its environment.

Question 8

Scanning techniques - investigating the biological approach

Answer 8

• Biological psychologists can scan the brain to determine the influence of biological structures on behaviour - fMRI scans on London taxi drivers showed that they have a larger hippocampi than a control group; this suggests that the hippocampus is involved in spatial navigation

Question 9

Experiments - investigating the biological approach

Answer 9

• Use lab experiments, particularly on animals to study the roles of inheritance and evolution on behaviour

Question 10

Case studies - investigating the biological approach

Answer 10

• People who get into accidents and suffer brain damage can be studied to tell us about the functions of different regions of the brain
• Phineas Gage suffered damage to his ventromedial frontal lobes after a iron rod went through his head - however, he then had difficulty making rational decisions and processing emotions
• We can therefore link these functions to this biological structure

Question 11

Genes

Answer 11

A part of the chromosome of an organism that carries the information in the form of DNA - this codes the physical and psychological features of an organism

Question 12

Neurochemistry

Answer 12

The study of chemical and neural processes associated with the nervous system that regulate psychological functioning - this includes the role of neurotransmitters and hormones

Question 13

Heredity

Answer 13

The passing of characteristics from one generation to the next through genes

Question 14

Neurotransmitters

Answer 14

Chemicals that travel across the synapse to transmit messages

Question 15

Biological structures

Answer 15

An arrangement of organisation of parts to form an organ, system or living thing

Question 16

The influence of genes on behaviour

Answer 16

• Heredity is the reason why offspring take after their parents in terms of psychological characteristics - genes carry instructions for particular characteristics
• As genes are transmitted from parents to offspring (inherited) behaviour geneticists suggest that behavioural characteristics such as intelligence, personality, mental illnesses etc are inherited in the same way as physical traits and characteristics
• Because genes code for specific characteristics, they cause the behaviour they code for
• Evidence from twin, family and adoption studies suggest certain behaviours are genetically determined - research has shown that the environment can play more of a role in determining behaviour than genetics

Question 17

Biological structures

Answer 17

• Areas of the brain can influence behaviour (fMRI taxi study) and other research has concluded that people with psychopathy, anti-social personality disorder, have reduced activity of the prefrontal cortex in comparison to control groups

Question 18

Neurochemistry

Answer 18

Neurotransmitters, such as serotonin can influence behaviour. Serotonin is an inhibitory neurotransmitter and so it prevents activity in the neuron 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 low levels of serotonin lead to people displaying depression.

Question 19

Genotype

Answer 19

The entire genetic make-up of an individual

Question 20

Phenotype

Answer 20

The genes that are physically expressed and observable due to environmental and inherited factors and genes.

Question 21

Genotypes and phenotypes

Answer 21

• Monozygotic twins have identical genotypes - they therefore have the same predisposition to develop normally and other characteristics
• For one of them to have a different development to the other, environmental factors must have influenced behaviour (phenotypes are different even if genotypes are the same)
• Their phenotypes, presumably due different environments, have led to different development - e.g. both may have a genotype and predisposition for PKU, but only one may express it or develop it due to their dietary differences

Question 22

Evolution, natural selection and Darwin

Answer 22

• Evolution is the result of population changes over successive generations (changes in the genetic make-up) due to the processes of natural selection caused by adaptation by some members of a species but not others - the environment only preserves advantageous traits that are passed on, and this includes behaviour as well as physical traits.

Question 23

Concordance

Answer 23

A percentage that shows how many twin pairs shared a characteristic studied.
Monozygotic twins would have close to 100% concordance if the behaviour is innate.
Dizygotic twins would have around 50% concordance if the behaviour is innate.
If the monozygotic concordance is not higher than the dizygotic or if there is not consistency in the concordance rate, it is a nurtured trait.
A high concordance rate = genetic (particularly in monozygotic)
A low concordance rate = nurture

Question 24

Evolved behaviors

Answer 24

Social releasers -
Bowlby suggested that babies are born with innate ‘cute’ features that encourage attention from adults; these activate innate adult attachment system or the tendency for adults to care for them. These enhance the survival of the infant as it is cared for, and they will eventually reproduce and live on, resulting in their physical characteristics becoming more widespread in the population.

Question 25

Evolved Behaviors pt2

Answer 25

Aggression -
- Men are more at risk of cuckoldry (being married to an adulterer) and so are deploying aggressive acts as a deterrent so that a partner is less likely to cheat. Additionally, aggression is more symbolic strength and power and so may be more attractive to females. Therefore, they enhance the men’s reproductive success increases due to the behavior, and so it becomes more widespread in society. (most behavior evolves to protect or reproduce)

Question 26

Reductionism

Answer 26

The belief that complex human behavior can be explained in terms of breaking it down to its smallest component parts such as the actions of genes, neurotransmitters or hormones.

Question 27

Concordance

Answer 27

A percentage that shows how many twin pairs shared a characteristic studied.
Monozygotic twins would have 100% concordance if the behavior was innate.
Dizygotic twins would have 50% concordance if behavior was innate.
Concordance would not be as evident if a behavior was nurtured.

Question 28

Concordance example

Answer 28

In a study of depression, a researcher investigated the genetic basis of the disorder, using a twin study of MZ and DZ twins. Both sets of twins grew up in similar environments. The researcher found the following concordance rates:
- MZ = 49%
- DZ = 17%
- Ordinary siblings = 9%

Question 29

Concordance example cont.

Answer 29

There is therefore some genetic basis as there was almost a 50% concordance rate for the MZ twins, and because they share the same genes and both have developed depression, there must be some genetic basis. Monozygotic twins have a higher concordance rate than DZ twins, supporting the genetic basis of the disorder. However, because the concordance rate is not 100%, other factors such as environmental experiences will affect behavior.

Question 30

Evaluating the biological approach

Answer 30

• Biological reductionism, Biological psychologists reduce the explanation for complex behaviours and human experience to simple biological elements (neurotransmitters).
• While this ignores other valid explanations, this is based on the scientific principle of parsimony,that complex behaviour should be explained in the simplest way possible.And has led to the development of drug therapies.
• Complex interaction between environmental experiences and the development of biological structures is not fully explained by a purely biological approach shown by work on plasticity
  => Maguire et al (2000) used MRI brain scans on taxi drivers who had completed a memory test about the streets of london, areas of their hippocampus were significantly larger than their controls.
• The effectiveness of drug treatments developed by biological psychologists, as well as biological theories have been demonstrated by highly controlled nomothetic research.Studies using techniques that provide objectivity such as blood test and FMRI.
• Explanation for disorders such as schizophrenia that cannot be fully explained by genetic inheritance, often take a diathesis stress explanation.Disorders can be the result of interaction between pre-existing vulnerability (disposition) ie genetic genotype and environmental stressors.( ie personal loss, abuse and drug use).
  ( combination)
• Biological determinism. Suggests human behaviour and thought processes are the result of biological processes outside our conscious control.This goes against the view that our decisions are driven by free will