5. biological approach Flashcards
biological ASSUMPTIONS
The biological approach suggests that everything psychological is at first biological, so to fully understand human behaviour, we must look to biological structures and processes within the body.
From a biological perspective, all thoughts, feelings, and behaviour ultimately have a physical basis in contrast to cognitive approach that sees mental processes of the mind as being separate from the physical brain.
THE NEUROCHEMICAL BASIS OF BEHAVIOUR
Neurochemistry refers to the action of chemicals in the brain.
Much of our thought and behaviour relies on chemical transmission in the brain this occurs
using neurotransmitters.
An imbalance of neurochemicals in the brain has been implicated as a possible cause of mental disorder, for example low levels of the neurotransmitter serotonin in OCD and overproduction of dopamine in schizophrenia.
THE GENETIC BASIS OF BEHAVIOUR
Psychological characteristics, such as intelligence, are inherited in the same way as height or eye colour 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 twins share the same characteristic if a characteristic is genetic, we would expect all identical (monozygotic) twins to be concordant (they share 100% of the same genes).
Whereas the same would not be true for non-identical (dizygotic) twins who share about 50% of the same genes.
In both cases the environment is assumed to be constant.
GENOTYPE AND PHENOTYPE
A person’s genotype is their actual genetic make-up, whereas phenotype is the way that genes are expressed through physical, behavioural, and psychological characteristics.
Despite having the same genes, the way identical twins’ genes are expressed (the phenotype) is different
illustrates what many biological psychologists would accept - much of human behaviour depends upon an interaction between inherited factors (nature) and the environment (nurture).
EVOLUTION AND BEHAVIOUR
The evolution of animals and plants is a fact. The theory of natural selection suggests that any genetically determined behaviour that enhances an individual’s survival (and reproduction) will continue in future generations.
In nature this selection takes place ‘naturally’ -
no one ‘decides, the selection occurs simply because some traits give the possessor certain advantages.
The possessor is more likely to survive, reproduce and pass on these traits.
If the individual survives but does not reproduce, the traits do not remain in the gene pool for successive generations.
AO3: limitation of the biological approach
deterministic
One limitation of the biological approach is that it is determinist.
The biological approach is determinist in that it sees human behaviour as governed by internal, genetic causes over which we have no control.
However, the way an individual’s genotype is expressed (phenotype) is heavily influenced by the environment. Not even identical twins who share the same genes look the same and think the same. Also, a purely genetic argument becomes problematic in the real world when we consider things such as crime. A criminal could excuse their actions by claiming their behaviour was controlled by a ‘crime gene’.
This suggests that the biological view is often too simplistic and ignores the mediating effects of the environment.
AO3: strength of the biological approach
real-world application - drug therapy
One strength of the biological approach is that it has real-world application.
Increased understanding of neurochemical processes in the brain is associated with the use of psychoactive drugs to treat serious mental disorders. For example, the biological approach has promoted the treatment of clinical depression using antidepressant drugs that increase levels of the neurotransmitter serotonin at synapses in the brain. Such drugs have been associated with the reduction of depressive symptoms.
This means that people with depression may be better able to manage their condition and live their lives in the community, rather than remain in hospital.
AO3: strength of the biological approach
scientific methods
Another strength of the approach is that it uses scientific methods of investigation.
In order to investigate the genetic and biological basis of behaviour, the biological approach makes use of a range of precise and highly objective methods. These include scanning techniques, such as fMRIs and EEGs. With advances in technology, it is possible to accurately measure physiological and neural processes in ways that are not open to bias.
This means that much of the biological approach is based on objective and reliable data.
