Outline and evaluate the biological approach (16 marks)
The biological approach is a perspective that emphasises the importance of physical processes in the
body such as genetic inheritance and neural function. The biological approach suggests that
everything psychological is at first biological, so to be able to fully understand human behaviour, we
must look at the biological structures and process in the body. These processes include the role of
genetics, neurotransmitters, neurochemistry and hormones. From a biological perspective, one key
assumption of the biological approach is that the mind “lives” in the brain meaning all thoughts,
feelings and behaviours have a physical basis. This is a contrast from the cogntive approach that sees
mental process of the mind as being separate from the physical brain.
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 for mental disorder. For
example, low levels of the neurotransmitter serotonin in OCD and overproduction of dopamine in
schizophrenia. This is very deterministic as it suggests that the level of neurotransmitter has caused
the mental disorder, putting aside other possible contributory factors.
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 which measure the extent to which
twins share the same characteristic and have genetic similarity. If a certain characteristic is genetic,
we would expect all monozygotic twins to be concordant i.e. they would share 100% of the same
genes, whereas the same would not be true for dizygotic twins who share about 50% of the same
genes. In both cases the environment as assumed to be constant, which is called the equal-
environments assumption.
A person’s genotype is the actual genetic make up, whereas is a phenotype is the way the genes are
expressed through physical, behavioural and psychological characteristics. Despite having the same
genes, the way identical twins are expressed is different ie the phenotype is different. This can be
seen through the example of PKU, a genetic disorder caused by the inheritance of 2 recessive genes.
This illustrates what many biological psychologists would accept that much of human behaviour
depends upon the interaction between inherited factors and the environment ie nature vs nurture.
The evolution of animals and plants is a fact. In in the 19th century Charles Darwin propose the
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 ie will be naturally selected. This happens in a similar way to a farmer
deciding which animals to use for breeding as they select the ones who possesses the most desirable
characteristics. Nature the selection takes place naturally, so 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.
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 is a strength of the biological approach as it means that people with depression may
The biological approach is a perspective that emphasises the importance of physical processes in the
body such as genetic inheritance and neural function. The biological approach suggests that
everything psychological is at first biological, so to be able to fully understand human behaviour, we
must look at the biological structures and process in the body. These processes include the role of
genetics, neurotransmitters, neurochemistry and hormones. From a biological perspective, one key
assumption of the biological approach is that the mind “lives” in the brain meaning all thoughts,
feelings and behaviours have a physical basis. This is a contrast from the cogntive approach that sees
mental process of the mind as being separate from the physical brain.
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 for mental disorder. For
example, low levels of the neurotransmitter serotonin in OCD and overproduction of dopamine in
schizophrenia. This is very deterministic as it suggests that the level of neurotransmitter has caused
the mental disorder, putting aside other possible contributory factors.
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 which measure the extent to which
twins share the same characteristic and have genetic similarity. If a certain characteristic is genetic,
we would expect all monozygotic twins to be concordant i.e. they would share 100% of the same
genes, whereas the same would not be true for dizygotic twins who share about 50% of the same
genes. In both cases the environment as assumed to be constant, which is called the equal-
environments assumption.
A person’s genotype is the actual genetic make up, whereas is a phenotype is the way the genes are
expressed through physical, behavioural and psychological characteristics. Despite having the same
genes, the way identical twins are expressed is different ie the phenotype is different. This can be
seen through the example of PKU, a genetic disorder caused by the inheritance of 2 recessive genes.
This illustrates what many biological psychologists would accept that much of human behaviour
depends upon the interaction between inherited factors and the environment ie nature vs nurture.
The evolution of animals and plants is a fact. In in the 19th century Charles Darwin propose the
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 ie will be naturally selected. This happens in a similar way to a farmer
deciding which animals to use for breeding as they select the ones who possesses the most desirable
characteristics. Nature the selection takes place naturally, so 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.
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 is a strength of the biological approach as it means that people with depression may
