Explain the Localisation of Brain Function assumption [4]
Biological Psychology explains that certain parts of the brain play different roles, and damage or
malfunction of individual parts can explain behaviours or mental illness. The cerebrum is the largest part of
the brain, split into 4 lobes with higher mental functions. The parietal lobe processes sensory information
for touch and body positing, the occipital lobe processes information from the eyes, the frontal lobe is
responsible for thinking and creativity and the temporal lobe is responsible for memory and auditory
information. There are two small parts in the brain which are associated with language- patients with
limited speech have been found to have a damaged Broca’s area, and those who struggle to understand
language may have a damaged Wernicke’s area. A famous demonstration of localisation of brain function
is Phineas Gage, who experienced major personality changes after being impaled with a rod from a railway
line.
Explain the Neurotransmitters assumption [4]
The nervous system is formed on a foundation of billions of neurons which have long branches allowing
them to connect with others, passing messages via neurotransmitters. Neurotransmitters are released
from presynaptic vesicles in one neuron and will then stimulate or inhibit receptors in another. An
imbalance of certain neurotransmitters can explain mental illness and negative behavioural traits, as
proven by the success of drugs which change the way neurotransmitters behave. Serotonin, for instance,
is responsible for mood appetite and sleep, and depression can be partially attributed to serotonin
deficiency. Dopamine gives people a ‘natural high’ and over production is linked with the positive
symptoms of psychotic illnesses such as hallucinations and mania.
Explain the Evolutionary Influences assumption [4]
Evolution is the changing of a species over time due to the most adaptive traits being passed down over
generations. This is based on the notion of Natural Selection, found in Darwin’s ‘On the Origin of Species’,
the individual with the characteristics best fitting to the environment are most likely to survive to
reproduce, thus passing down those genes. The Environment of Evolutionary Adaptation in the place to
which a species will change behaviours to survive within, and overtime biological changes will also occur.
This can explain why humans have such a relatively large brain, to keep up with the increasingly complex
societal structure.
Explain how the biological approach might explain relationship formation [6]
Over time, humans have evolved to have adaptive traits which increase chances of survival and
reproduction, so unsurprisingly a number of adaptations are related to finding a healthy, fertile mate. Men
often find curvaceous bodies, large eyes and glossy hair attractive as these are all signs of youth and
fertility. Parental Investment Theory explains that because a woman invests so much emotionally and
physically into her child, she is likely to seek a partner who will be able to provide in terms of food and
shelter etc. A study by Buss on 10,000 people from all over the world showed that women were more
concerned with traits such as ambition and drive, whereas men favoured ascetic qualities.
Neurotransmitters play a role in the way we interact with partners, in particular oxytocin, or the ‘love
hormone’. There are high levels of oxytocin in the first 6 months of a relationship, and these levels drop
when physical contact is reduced, which explains the feelings of anxiety when one is separated from their
partner. Dopamine is associated with motivation and drive, so setting the goal of finding a partner gives a
hit of it; this is also linked to evolutionary influences as if you want your genes to be passed on you need
to be in a romantic relationship, so the mind encourages us to pursue one.
