The Biological Approach Flashcards
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, the mind lives in the brain - meaning that all thoughts, feelings and behaviour ultimately have a physical basis. This is in contrast to, say, the cognitive approach that see 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 (neural’ refers to 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.
Genotype and phenotype
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 - see also the example of PKU (see facing page). This illustrates what many biological psychologists would accept, that 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. In the 19th century, Charles Darwin proposed a theory to explain this fact - the theory of natural selection. The main principle of this theory is that any genetically determined behaviour that enhances an individual’s survival (and reproduction) will continue in future generations, i.e. be naturally selected. This happens in a similar way to a farmer deciding which animals to use for breeding - the farmer selects the ones who possess desirable characteristics. For example, if one of a farmer’s cows has a high milk yield the farmer chooses this cow for further breeding so his stock of cows become progressively better milk producers.
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, remain in the gene pool for successive generations.
reproduce and pass on these traits. If the individual survives but does not reproduce, the traits do not
Evolution of behaviour- as seen in animals and humans
-memory-human memory evolved because it provided advantages
-attachment-bowlby argued that attachment to a primary caregiver is adaptive
-mental disorder-some mental disorders such as ocd may have a genetic basis. Psychologists argue therefore that these genes must have some adaptive advantage.
Strength- real world application
Increased understanding of neurochemical processes in the brain is associated with the use of psychoactive drugs to treat serious mental disorders. Biological approach has promoted treatment of clinical depression using antidepressant drugs that increase levels of the neurotransmitter serotonin at synapses in the brain. Reduce depressive symptoms. People with depression can manage their condition.
Counterpoint-antidepressant drugs don’t work for everyone. 21 antidepressant drugs were compared and found wide variations in their effectiveness. More effective than placebos, researchers concluded the effectiveness of antidepressants were mainly modest. Suggests that brain chemistry alone may not account for all cases of depression.
Strength- scientific method
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. Include scanning techniques like fMRI and EEGs. With advances in technology it is possible to accurately measure phsyiological and neural processes in ways that are not open to bias. Based on objective and reliable data.
Limitation-deterministic
The biological approach is deterministic because it sees human behaviour as governed by internal, genetic causes over which we have no control. However we have seen that the way in which an individuals genotype is expressed 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 when we consider things like crime. Could a criminal excuse their behaviour because of a crime gene? Suggests biological approach is often too simple and ignores mediating effects of the environment.
Limitation natural selection
Can’t prove natural selection has happened as we can’t show evolution happening- others claim you can due to fossils.
