The Biological Approach

1. The Biological Approach PSYB4

2. Essay title Can you answer this question? Discuss the biological approach in psychology. Refer to at least one other approach in your answer (12 marks)

3. What is the biological approach? • The biological approach combines psychology and biology to provide physiological explanations for human behaviour. • Biological psychology tries to explain how we think, feel and behave in terms of physical factors within the body. Physiology: the study of the body and its parts and how they function

4. Basic assumptions • Investigates how biology, especially neurobiology impacts on behaviour. • Much of human behaviour has a physiological cause which may be genetically or environmentally altered. • Genes affect behaviour and influence individual psychological differences between people. Evolutionary psychology considers genetic influences in common behaviours • Psychologists should study the brain, nervous system and other biological systems, e.g. hormones, chemicals acting on the brain

5. Causal or functional levels? • The causal level of analysis concentrates on the physiological processes underlying behaviour • The functional level of analysis is the evolutionary basis of behaviour, including genetics.

6. Causal level of analysis • Our physical body consists of millions of cells which are communicating through electrical and chemical signals all the time. • Behaviour is controlled by the nervous system. The nervous system is divided into the central nervous system (CNS) and the peripheral nervous system (PNS). • The central nervous system consists of the brain and the spinal cord. • The peripheral nervous system consists of the autonomic nervous system (ANS) and the somatic nervous system (SNS).

7. Human nervous system Peripheral nervous system (PNS) Central nervous system (CNS) Autonomic nervous system Somatic nervous system Brain Spinal cord Sympathetic nervous system Parasympathetic nervous system The organisation of the human nervous system

8. Video • http://www.ngfl-cymru.org.uk/vtc/2008-09/psychology/ebook/Animeiddiadau/Saesneg/synaps/synaps.html

9. Functional level of analysis Charles Darwin emphasised two main concepts in evolutionary theory: • natural selection • sexual selection

10. Natural selection • 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. • These behaviours need to adapt to the environment that the animal is living in which is dependent on three principles: • the principle of diversity - the variety within a species • the principle of interaction - which is how this variety of species adapt and fit in with the environment e.g. animals that breathe air wouldn’t be able to permanently live under water • the principle of differential amplification - those who adapt to their environment will reproduce and those that do not will die out.

11. Sexual selection • Males have an abundance of sperm and can reproduce with as many females as they want. • Females however, are limited by the amount of eggs she produces and the fact that she has to carry the baby for 9 months and then raise it till the age of 18. • Females therefore will be more particular about who fathers their children due to the investment they have to make.

12. Genetic basis of behaviour • The basic units of heredity are called genes • Genes function in pairs and the recombination of genes from parents to offspring provides the basis for genetic variability • Genes only determine the potential for characteristics (genotype) • The observable characteristics of an individual (phenotype) depend on the interaction of genetic and environmental factors.

13. Methods of investigating the genetic basis of behaviour There are different methods for investigating the genetic basis of behaviour: • twin studies • family studies • adoption studies • selective breeding

14. Genetic basis of behaviour • There is evidence from twin, family and adoption studies to suggest that certain behaviours, for example, intelligence, are genetically determined • Research has shown that the environment can play more of a role in determining behaviour than genetics • Selective breeding studies have demonstrated how a number of behavioural characteristics, for example aggression, can have a genetic basis

15. Research methods • The biological approach draws on concepts from the hard sciences and research tends to be highly scientific in nature • The most common methods include laboratory experiments and observations • Objective brain recording and scanning techniques are also used

16. Strengths of biological approach • It is a scientific approach. This suggests that we can find cause and effect relationships of both physiology and behaviour. • Scientific approach lends credence to study of psychology – establishes psychology as a respectable science • Impact of biology on behaviour can lead to treatment and intervention to those suffering • Understanding how an abnormal brain works can shed light on normal brain functioning • Measurements can be objective as it can be performed by machines which have no vested interest in the outcome e.g. PET scans, EEGs etc. Use of complex machinery allows accurate and precise measurements

17. Limitations of biological approach • 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. • This approach is reductionist by stating that all human behaviour can be explained through biological processes and we are therefore not unique as individuals. 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. • 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

18. Essay title Can you answer the question? Discuss the biological approach in psychology. Refer to at least one other approach in your answer (12 marks)