4.2.1 The Biological Approach Flashcards
What is the biological approach?
The biological approach is a perspective that emphasises the importance of biological and physical structures and processes, to fully understand human behaviour.
When, and how, did the biological approach emerge?
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.
What are the key assumptions of the biological approach?
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)
What are genes?
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.
What do biological psychologists believe about genes?
Biological explanations of behaviour often focus on genes. They believe that genes are responsible for our psychological features as well as physical features.
What is a genotype?
Genotype refers to the set of genes that an individual possesses
What is a phenotype?
Phenotype refers to the characteristics of an individual, determined by both genes and the environment.
What do biological psychologists believe about genotypes and phenotypes?
Biological psychologists believe that much of human behaviour is determined by an interaction between inherited factors (nature) and the environment (nurture).
What are monozygotic twins?
MZ twins share the same genotype, so are 100% identical twins.
What are dizygotic twins?
DZ twins share 50% of the same genes, so are not identical.
What are twin studies and how are they used?
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.
How can PKU be applied to genotypes and phenotypes?
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).
What did McGuffin et al’s twin study show?
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.
What do biological psychologists believe about biological structures?
Biological psychologists believe that the structure of organs, such as the brain, the CNS, PNS and endocrine system, determine our behaviour.
Describe how the endocrine system can influence our behaviour?
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.
