Plasticity and Functional Recovery of the Brain after Trauma

Question 1

Plasticity

Answer 1

Also referred to as neuroplasticity or cortical remapping. This describes the brain’s tendency to change and adapt (functionally and nphysically) as a result of experience and new learning.

Question 2

Functional recovery

Answer 2

A form of plasticity. Following damage through trauma, the brain’s ability to redistribute or transfer functions usually performed by a damaged area(s) to other undamaged area(s).

Question 3

Cross-modal reassignment

Answer 3

Where the brain adapts and changes and so uses an area that would normally process a certain type of sensory information (such as sight) for a different type of sensory information instead (such as sound).

Question 4

What happens in the brain during recovery?

Answer 4

The brain is able to rewire and reorganise itself by forming new synaptic connections close to the
area of damage (a bit like avoiding roadworks on the way to school by finding a different route).
Secondary neural pathways that would not typically be used to carry out certain functions are
activated or ‘unmasked’ to enable functioning to continue, known as functional recovery.

Question 5

Functional Recovery of the Brain after Trauma

Answer 5

Following physical injury, unaffected areas of the brain are often able to adapt and compensate for
those areas that are damaged known as functional recovery. Healthy brain areas may take over the
functions of those areas that are damaged, destroyed, or even missing. Neuroscientists suggest that
this process can occur quickly after trauma (spontaneous recovery) and then slow down after
several weeks or months. (Doidge, 2007).

Question 6

What structural changes in the brain support functional recovery?

Answer 6

1. Axonal sprouting - The growth of new nerve endings which connect with other undamaged
   nerve cells to form new neuronal pathways.
2. Reformation of blood vessels.
3. Recruitment of homologous (similar) areas on the opposite side of the brain to perform
   specific tasks. An example would be if Broca’s area were damaged on the left side of the
   brain, the right-sided equivalent would carry out its functions. After a period of time,
   functionality may then shift back to the left side.

Question 7

What happens with age

Answer 7

Functional plasticity tends to reduce with age. The brain has a greater propensity for reorganisation
in childhood as it is constantly adapting to new experiences and learning.

Question 8

A03 - Research into plasticity

Answer 8

1. There is research support for plasticity.
2. Maguire et al. (2000) studied the brains of London taxi drivers and found significantly more
   grey matter in the posterior hippocampus than in a matched control group. This part of the
   brain is associated with the development of spatial and navigational skills in humans and
   other animals.
3. The research findings of this study indicate that as new knowledge is acquired this grey
   matter in the hippocampus grows.
4. Therefore, this supports the theory of neuroplasticity.

Question 9

A03 - Cross modal reassignment

Answer 9

1. Research support also supports cross-modal reassignment.
2. Grafman (2000) has shown that when a brain region does not receive sensory data as
   expected, say because a person has become blind, this brain region may become
   repurposed for another sense, such as touch (cross-modal reassignment). This can enable
   blind people to “see” Braille text with their fingers.
3. Likewise, some blind people learn to reuse their visual centres for hearing sounds, thus
   becoming capable of “echolocation” to navigate around environments (Thaler & Goodale,
   2010).
4. This means that neuroplasticity is not only supported by robust, empirical lab research, it
   also has a practical application to the changes that can occur to people in real life.

Question 10

A03 - Evidence for the recruitment for homologous areas

Answer 10

1. Research also supports the recruitment of homologous areas.
2. Grafman (2000) reported the case study of a youth with a right parietal lobe injury. The left
   parietal lobe took over some functions normally occurring on the right side, i.e. the
   recruitment of homologous areas in the left parietal lobe occurred.
3. As we know from Sperry’s research the left hemisphere controls movement in the right side
   of the body and the right hemisphere controls movement in the left side of the body. The
   youth then had difficulty with tasks normally occurring on the left side, because some
   right-side equivalents had taken over left-side brain resources.
4. Grafman’s research is further evidence that neuroplasticity occurs in some people following
   brain trauma.