Outline and evaluate plasticity and/or functional recovery after trauma. (16 marks)
Plasticity is the ability of the brain to change and adapt its structure and function in response to the
environment, for example new learning. According to Gopnik, the brain increases the number of synaptic
connections throughout infancy, peaking at around 1500 connections at age 3. Through the process of synaptic
pruning – which occurs throughout life – the number of connections decreases as rarely-used connections are
deleted, whilst frequently used connections are strengthened.
Functional recovery is a form of plasticity, whereby after trauma, the brain has the ability to redistribute
functions that would have been performed by the now damaged areas to unaffected areas. This ability to
recover decreases with age. Neuronal unmasking is where dormant areas of the brain near damaged areas are
activated, and these connections are strengthened to allow functioning to continue. Axonal sprouting is where
new nerve endings grow and connect with undamaged neurons, creating new connections. Homologous areas
on the opposite hemisphere to the damage may be recruited to perform specific tasks. Functional recovery may
occur quickly after trauma, but will then slow after several weeks; rehabilitative therapy, such as constraint-
induced therapy, may be needed for further recovery.
A strength of plasticity is that there is research support. Maguire studied the brains of taxi drivers who
had to take ‘The Knowledge’ exam. In comparison to a control group, the posterior hippocampus – which deals
with spatial awareness and navigation skills – regions were found to be larger in the taxi drivers. Draganski found
similar learning-induced changes when comparing the brains of medical students three months before and after
their final examinations. It is clear that the necessary regions of the brain for learning were structurally
developed in response to preparing for exams, supporting the idea of plasticity as the brain adapted to excel in
its environment.
A strength of plasticity is that it has derived successful practical applications in physical therapy for
stroke patients. Functional recovery recognises that the brain can fix itself after trauma to a certain extent.
Understanding plasticity has led to movement and electrical therapies that allow further recovery after
spontaneous recovery has slowed down. However, plasticity can also have negative consequences.
Ramachandran and Hirstein found that 60-80% of amputees experience phantom limb syndrome, whereby they
still feel sensations of their missing limb, due to cortical remapping in the somatosensory cortex. The concept of
plasticity is certainly strengthened by its practical applications in aiding functional recovery; however it is
important that we also focus on its potentially unpleasant consequences and how to deal with these.
A limitation of plasticity is that it does not acknowledge individual differences. Supposedly plastic
abilities decline with age; however, Bezzola studied the fMRI scans of novice golfers aged 40-60 and found that
they had reduced motor cortex activity when playing compared to a control group, indicating that more efficient
neural connections had been made during training. Furthermore, Schneider found that cognitive reserve affects
a brain-damaged individual’s likelihood of a disability-free recovery. It may be that individual factors – such as
age, cognitive reserve, pre-existing factors and how quickly treatment is accessed – affect the brain’s plastic
abilities, however the current explanations of plasticity do not account for this.
Word count: 191 + 334
Plasticity is the ability of the brain to change and adapt its structure and function in response to the
environment, for example new learning. According to Gopnik, the brain increases the number of synaptic
connections throughout infancy, peaking at around 1500 connections at age 3. Through the process of synaptic
pruning – which occurs throughout life – the number of connections decreases as rarely-used connections are
deleted, whilst frequently used connections are strengthened.
Functional recovery is a form of plasticity, whereby after trauma, the brain has the ability to redistribute
functions that would have been performed by the now damaged areas to unaffected areas. This ability to
recover decreases with age. Neuronal unmasking is where dormant areas of the brain near damaged areas are
activated, and these connections are strengthened to allow functioning to continue. Axonal sprouting is where
new nerve endings grow and connect with undamaged neurons, creating new connections. Homologous areas
on the opposite hemisphere to the damage may be recruited to perform specific tasks. Functional recovery may
occur quickly after trauma, but will then slow after several weeks; rehabilitative therapy, such as constraint-
induced therapy, may be needed for further recovery.
A strength of plasticity is that there is research support. Maguire studied the brains of taxi drivers who
had to take ‘The Knowledge’ exam. In comparison to a control group, the posterior hippocampus – which deals
with spatial awareness and navigation skills – regions were found to be larger in the taxi drivers. Draganski found
similar learning-induced changes when comparing the brains of medical students three months before and after
their final examinations. It is clear that the necessary regions of the brain for learning were structurally
developed in response to preparing for exams, supporting the idea of plasticity as the brain adapted to excel in
its environment.
A strength of plasticity is that it has derived successful practical applications in physical therapy for
stroke patients. Functional recovery recognises that the brain can fix itself after trauma to a certain extent.
Understanding plasticity has led to movement and electrical therapies that allow further recovery after
spontaneous recovery has slowed down. However, plasticity can also have negative consequences.
Ramachandran and Hirstein found that 60-80% of amputees experience phantom limb syndrome, whereby they
still feel sensations of their missing limb, due to cortical remapping in the somatosensory cortex. The concept of
plasticity is certainly strengthened by its practical applications in aiding functional recovery; however it is
important that we also focus on its potentially unpleasant consequences and how to deal with these.
A limitation of plasticity is that it does not acknowledge individual differences. Supposedly plastic
abilities decline with age; however, Bezzola studied the fMRI scans of novice golfers aged 40-60 and found that
they had reduced motor cortex activity when playing compared to a control group, indicating that more efficient
neural connections had been made during training. Furthermore, Schneider found that cognitive reserve affects
a brain-damaged individual’s likelihood of a disability-free recovery. It may be that individual factors – such as
age, cognitive reserve, pre-existing factors and how quickly treatment is accessed – affect the brain’s plastic
abilities, however the current explanations of plasticity do not account for this.
Word count: 191 + 334
