(16 marks)
Plasticity is the brain tendency to change and adapt throughout a person’s life
(functionally and physically) as a result of experience and new learning. Research suggests
that the brain continues to create new neural pathways and alter existing ones in response
to changing experiences. As we get older synaptic connections that are not used are
removed and the ones used are strengthened. (Synaptic pruning)
The brain also appears to show evidence of functional recovery, which is the transfer of
functions from a damaged area of the brain after a trauma or physical damage to other
undamaged areas. Neuroscientists suggest that this process can occur quickly after a trauma
(spontaneous recovery) and then slow down after several weeks or months. During
recovery, the brain rewires and organises itself by forming new synaptic connections.
Secondary neural pathways are activated ‘unmasked’ to enable functioning to continue and
recovering any damage that has occurred in specific regions.
A strength of plasticity and functional recovery is real life application. This is as research
into the processes of plasticity and functional recovery has led to the development of
neurohabilitation which uses movement therapy and electrical stimulation of the brain to
counter the deficits in motor and cognitive functions following accidents or injuries like
strokes. Thus, research in this area is useful in real life as it helps improve cognitive
functions of people suffering from injuries.
Another strength of plasticity is there is research to support it. For example, Maguire et al
found that the posterior hippocampus volume of taxi driver’s brains in London correlated
positively with their experience as taxi driver and there was a significant difference between
the brain of the control group and the drivers. Evidence from this research shows the brain
can alter permanently due to regular exposure to a particular task. Therefore, this research
supports plasticity as it implies life experience can cause plasticity in the brain. However, a
limitation of Maguire study is we can’t be sure that the difference is due to ‘knowledge’ as
the taxi drivers were not tested before becoming taxi drivers so a clear change in the
structures of the brain as a result of their experiences cannot be concluded. It may be the
drivers already had larger hippocampus before becoming taxi drivers. Thus, a cause and
effect relationship between changes in the brain and experience is unable to be established.
Another strength of plasticity is there is supporting research for it. For example, Kuhn et al
found that after participants played video games for 30 minutes over a two-month period
there was a significant increase in grey matter in various regions of the brain. This matter
because Kuhn provides evidence for brain plasticity and shows how experience playing
video games can cause structural changes in the brain.