8. Biological Approach Flashcards
significance of the change from social learning theory to the biological approach
paradigm shift from the 1980s onwards to psychology being viewed as a science in its own right due to advances in technology
Outline the biological approach
1. assumption
The biological approach argues all human behaviour can be explained in terms of physical structures and processes in the brain and body such as genetics, neurochemistry and the nervous system.
INCLUDING:
(2) genetic basis of behaviour
(3) influence of biological structures and neurochemistry
(4) evolution and behaviour
genotype
a persons actual genetic make-up
phenotype
the way an individuals genes are expressed through physical, behavioural and psychological characteristics (ie the observable appearance of the trait)
monozygotic twins
identical twins, share 100% of same genes
dizygotic twins
non-identical twins, share 50% of same genes
concordance rates
how often twins share the same characteristic
Outline the biological approach
2. the genetic basis of behaviour
One way of testing the genetic basis for behaviour is through twin studies and measuring concordance rates (how often both twins share the same characteristic)
If identical (monozygotic - MZ) twins have a higher concordance rate for a certain characteristic, such as schizophrenia, than non-identical (dizygotic - DZ) twins, this would suggest a genetic basis.
This is because MZ twins share 100% of the same genes whilst DZ twins share 50%.
Genetic influence occurs through genotypes and phenotypes.
A person’s genotype is their actual genetic make-up, whereas a phenotype is the way that genes are expressed through physical, behavioural and psychological characteristics (i.e. the observable appearance of the trait).
The expression of a genotype is influenced by environmental factors.
For instance, MZ twins often look slightly different because, despite identical genotype, the way their genes are expressed (the phenotype) might be different due to, for example, one exercising more than the other. Although identical genotypes mean MZ twins have a predisposition to develop the same way, different environments can intervene and change their phenotypes.
what is meant by localisation of brain function
specific functions (eg language and memory) come from specific locations in the brain
eg language centre located in Broca’s area
what are neurotransmitters
chemical messengers that communicate messages between neurons
it is thought that certain neurotransmitters influence certain behaviours (eg serotonin maintains a stable mood)
Outline the biological approach:
3. the influence of biological structures and neurochemistry
Biological psychologists have also studied the influence of biological structures on behaviour, including the brain and the nervous system.
A key idea in brain research is that specific functions (e.g. language and memory) might come from specific locations in the brain.
This is known as localisation of function.
For example, it is thought our language centre is located in an area known as Broca’s area.
Neurochemistry is another area of study in biopsychology focused on neurotransmitters (chemical messengers that communicate messages between neurons).
It is thought certain neurotransmitters influence certain behaviours (eg. serotonin maintains a stable mood)
what is meant by evolution
Evolution refers to gradual changes in an inherited characteristic of a species over many generations.
Darwin explained this in terms of ‘survival of the fittest’ (i.e. the best adapted to the local environment), meaning that any characteristic or behaviour that increases the chance that an individual will survive and reproduce, would be passed onto future generations.
what is meant by natural selection
The way that any genetically determined behaviour that enhances the ability to survive and reproduce will continue in future generations.
what is meant by sexual selection
a type of natural selection and competition for mates along with the development of characteristics that aid reproductive success drive evolution
eg mate preference strategies
Outline the biological approach:
4. evolution and behaviour
Another way of studying the influence of biology on behaviour is through evolution.
Here researchers can investigate changes in inherited characteristics over successive generations.
The main mechanism behind evolution is natural selection.
Individuals within a species differ from each other in terms of their characteristics and behaviour, and at least some of this variation is inherited.
Because individuals must compete for access to resources (e.g. food), those who survive this competition and
reproduce wiltend lose novours that are most likely to lead to survival and reproductive success.
These behaviours are then passed on to their offspring and will become more widespread in the population of the species.
Successive generations will strategies develop behaviours that are even more likely to lead to survival and reproductive success.
