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
According to Darwin, sexual selection is a form of natural selection in which competition for mates and the development of traits that enhance reproductive success drive evolution.
Involves:
- Intrasexual selection (mate competition) where members of the same sex compete with one other for members of the opposite sex. Those who ‘win’ are able to mate and pass on their genes to the next generation.
- Intersexual selection (mate choice) involves one sex having preferences for members of the opposite sex who possess certain qualities.
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 will tend to have behaviours 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 develop behaviours that are even more likely to lead to survival and reproductive success.
Evaluate the biological approach:
STRENGTHS
P: scientific
E: focuses on measurable/observable behaviour that can be tested in controlled conditions
E: eg. brain scanning techniques like fMRI and EEGs are highly controlled and make changes in activity clear to observe and measure. Eg. Tulving’s research into types of LTM.
L: supported by empirical evidence
P: practical applications
E: drug therapies which aim to correct neurochemical imbalances in the brain treat a variety of mental illnesses
E: Soomro et al (2009) SSRIs (antidepressants) significantly more effective than placebos in treating OCD
L: can be used to improve people’s lives in the real world and drugs are cost effective so have benefits for the economy
E: although, CBT is just as effective than drugs for treating depression (81%) and doesn’t have side effects
Evaluate the biological approach:
LIMITATIONS
P: family and twin studies struggle to distinguish between the influence of nature and nurture
E: assumes twins and members of the same family all have genetic similarities and therefore any similarities in behaviour must be genetic - may not be the case
E: eg twins and members of same family are usually all exposed to the same environment too
L: findings could just as easily be interpreted as supporting nurture rather than nature. theory may be based on flawed evidence
E: middle ground, interactionist, approach may be more appropriate, eg. diathesis-stress model
P: biologically reductionist
E: reduces human behaviour down to the activity of specific variables such as biological (internal) factors - ignores the role of environmental (external) factors
E: eg studies by Pavlov, Skinner, and Bandura all show that various behaviours can be learned in animals and humans (eg. aggression)
L: limited/oversimplifies complex behaviours which require a more holistic explanation
E: ALSO, evolutionary explanations assume large numbers of humans behave in the same way due to passed down behaviours, which ignores the role of culture
P: biologically determinist
E: behaviour is caused by factors outside of our control (internal biological factors) - struggles to explain why MZ twins who share 100% DNA don’t have a %100 concordance rate for certain behaviours
E: eg Nestadt et al (2010) MZ twins have 68% concordance rate for OCD
L: ignores free will/removes individual autonomy.
E: BUT, may help remove blame for sufferers
value of the biological approach
- drug therapies for disorders such as OCD (SSRIs) and anxiety (BZs) are successful, widespread, cost effective treatments
- contributed cause and effect with regards to genetic influences through twin, family, adoption studies
- brought psychology back to being recognised as a distinct science in its own right (respected, scientific status)
- economics benefits: investment in drug companies eg. NHS funding given to large pharmaceutical companies
- later combined with cognitive approach for cognitive neuroscience
- used advances in technology to aid the development of empirical research techniques eg brain scanning
- avoids victim blaming (biological determinism)
key assumptions of the biological approach
- humans should be studied objectively and empirically following the scientific method
- There is a direct correlation between brain activity and cognition (cognitive neuroscience)
- Biochemical imbalances can affect behaviour (neurotransmitters)
- Brain physiology can affect behaviour (brain structure/lateralisation of function)
- Behaviour can be inherited (determined by genetic information, evolution)
biological approach:
free will v determinism
strongly biologically deterministic
behaviours are generated from biological roots outside our control (genes, brain structure, evolution, neurochemistry)
biological approach:
nature v nurture
nature
one of the core assumptions of this is that behaviour can be passed through the genetic make up of the individual
biological approach:
holism v reductionism
strongly reductionist
biological reductionism
reduces human behaviour down to its lowest level in terms of the activity of specific variables such as genetics and neurochemistry
ignores the role of environmental factors, eg. Pavlov, Skinner, Bandura all show that various behaviours can be learned in animals and humans
biological approach:
idiographic v nomothetic
nomothetic
we share a common physiology and biochemistry and that it is differences within these that explain the variance in behaviour between people
although case studies are used, these are to help comparison with typical behaviour and they are used to test general theories
biological approach:
scientific methods
scientific
focuses on observable and measurable behaviour which can be tested in controlled conditions
eg. braun scanning techniques like fMRI and EEGs are highly controlled and make changes in activity clear to observe and measure
biological approach:
extrapolation
animal research is widely used by the biological approach as it sees humans as being physiologically similar to animals
tests on animals are therefore appropriate and helpful
eg. Lorenz’s geese, MAOA gene research on mice
biological approach:
practical applications
drug therapies which aim to correct neurochemical imbalances in the brain treat a variety of mental illnesses
Soomro et al (2009) SSRIs (antidepressants) significantly more effective than placebos in treating OCD
BUT, CBT is equally as effective as drugs for depression (81% - March et al (2007))
