Biological Approach

Question 1

What is the biological approach

Answer 1

This approach combines psychology and biology to provide psychological explanations for human behaviour.
The biological approach look at the influence of genes, biological structures, neurochemistry on behaviour, genotypes and phenotypes, genetic basis of behaviour, evolution and behaviour.
This approach tries to explain how we think, feel and behave in terms of physical factors with the body.

Question 2

What is physiology

Answer 2

The study of the body and its parts and how they function

Question 3

Basic assumptions of this approach

Answer 3

• the approach investigates how biological structure and functions of the brain including localisation of function, affect our behaviour.
• much of human behaviour has a biological cause which may be genetically or environmentally altered
• Genes affecting our behaviour including phenotypes and genotypes which influence individual differences between people.
• the nervous system including hormones and neurotransmitters affect behaviour.
• infections of the brain can play a role in mental illness.
• evolutionary psychology considers genetic influences in common behaviours through natural selection.

Question 4

Genetic basis of behaviour

Answer 4

We differ from each other due to our genetic instructions (genes) e.g personality, IQ.
Heritability refers to the amount of variation in a trait (behaviour) within a population that can be attributed to genetic differences.
The more a trait is influenced by genetic behaviour factors, the greater the heritability.
E.g twin studies suggest IQ variance is affected by as much a 60-80% due to genes.
Genetics are thought to influence the risk of mental illness e.g schizophrenia. Genetically, people can be predisposed

Question 5

What are the methods of investigating the genetic basis of behaviour

Answer 5

We can investigate the extent to which psychological characteristics are affected by inheritance from parents and evolution genetic basis of behaviour by using:
Twin studies
Family studies 
Adoption studies 
Selective breeding

Question 6

Why are Twin studies useful.

Answer 6

Twins are useful when investigating the genetic basis of behaviour. This is because we can see the likelihood of certain traits having a genetic basis by comparing the concordance rates between pairs of twins. If monozygotic twins (identical twins) are found to have a higher concordance rate than dizygotic twins (non identical), this would suggest a genetic basis. This is because MZ twins share 100% of each other’s genes, whilst DZ twins share about 50% (the same as any siblings)

Question 7

Genotype

Answer 7

A persons genotype is their actual genetic makeup.

Question 8

Phenotype

Answer 8

These are the ways that the genes are expressed through physical, behavioural and psychological characteristics.

Question 9

What influences the way genotypes are expressed (phenotype)

Answer 9

The environment has influence on how our genotypes are influenced e.g identical twins may look different due to one exercising more, dyed hair etc.

Question 10

What is the natural selection theory

Answer 10

Animals with particular traits that provide them with an advantage are more likely to survive and reproduce thereby passing on their ‘adaptive traits’ to their offspring.

Question 11

What is included in the central nervous system

Answer 11

controls most functions of the body and mind. It consists of two parts: the brain and the spinal cord.

The brain is the center of our thoughts, the interpreter of our external environment, and the origin of control over body movement. Like a central computer, it interprets information from our eyes (sight), ears (sound), nose (smell), tongue (taste), and skin (touch), as well as from internal organs such as the stomach.

The spinal cord is the highway for communication between the body and the brain. When the spinal cord is injured, the exchange of information between the brain and other parts of the body is disrupted.

Question 12

What’s included in the peripheral nervous system

Answer 12

The peripheral system allows the brain and spinal cord to receive and send information to other areas of the body, which allows us to react to stimuli in our environment. The nerves that make up the peripheral nervous system are actually the axons or bundles of axons from nerve cells or neurons.

Question 13

What do excitatory neuron transmitters do

Answer 13

They trigger nerve impulses and stimulate the brain Ito action.

Question 14

What do inhibitory neurotransmitters do

Answer 14

They inhibit nerve impulses and calm the brain and balance mood.

Question 15

What are hormones

Answer 15

These are chemical substances that help to regulate processes in the body.
Hormones are secreted by glands and travel to their target organs in the bloodstream.
Hormones cause physiological reaction in the target cells and alter their activity.
Several hormones have been linked to behaviour. E.g testosterone and aggression have been linked.

Question 16

What is the cerebral cortex.

Answer 16

This is the outer layer of the brain composed of folded grey matter and it plays an important role in consciousness.
It is also responsible for many ‘higher order’ functions such as thinking, language.

Question 17

What can happen if you cause destruction or degeneration of brain cells.

Answer 17

It can result in possible behavioural changes. E.g if the frontal lobe is injured, then there will be a difference int the way they speak, control facial expressions, and their emotions.

Question 18

What happened to phineas gage

Answer 18

He survived an accident in which a large rode went through his brain.
Although he survived, his personality changed from being sociable to being hostile.
Phineas became antisocial, bad mannered, and violent.
There was no treatment, however in phineas’ case, he recovered socially. Neurosurgeons can perform a lobotomy in serious cases.

Question 19

What are the most common research methods used for the biological approach

Answer 19

Laboratory experiments and observations.

Objective brain recoding and scanning techniques are also used.

Question 20

What is the evolutionary theory made by Charles Darwin

Answer 20

This theory suggested that evolution is the change in the characteristics of a species over several generations and relies on the process of natural selection.He outlined two main concepts in his theory- natural selection and sexual selection.

Question 21

How does the evolutionary theory explain behaviour.

Answer 21

It suggests that these behaviours are genetically determined and passed on from generation to generation because they increase our chances of survival. One example is attachment, it is also used to explain aggression.

Question 22

Strengths of the biological approach

Answer 22

It is a scientific approach. This suggests that we can find cause and effect of biology on behaviour.
Use of scientific method is highly controlled increasing reliability and validity of findings.
Impact of biology on behaviour can lead to treatment.
Scientific measurements are objective as it can be performed by machines which have no vested interest in the outcome e.g PET scans.

Question 23

Limitations of the biological approach

Answer 23

It is a deterministic approach as it believes that we are determined by our physiological, genetic or evolutionary make-up, which implies that we have no free will.
This approach is reductionist by stating that all human behaviour can be explained through a single biological process.
Dangers of looking for a biological cause of all behaviour led to problems e.g searching for the ‘criminal gene’.
Biological approach ignores the role of the environment.
It is very difficult to separate the effects of nature (genes) from nurture (environment).
Laboratory experiments can lack ecological validity.