Functional recovery

Question 1

Define neuronal reorganisation

Answer 1

• This is where healthy areas of the brain take over functions of damaged, destroyed or missing areas of the brain.

Question 2

How does the brain rewire and reorganise itself?

Answer 2

• By forming new synaptic connections close to the area of damage.
• Secondary neural pathways are activated, or ‘unmasked’ to enable functioning to continue often in the same ways as before.
• This process is supported by structural changes in the brain.

Question 3

What are the 2 structural changes in the brain?

Answer 3

1. Axonal sprouting.
2. Reformation of blood vessels.

Question 4

What is axonal sprouting

Answer 4

• Is the growth of new nerve endings which connect with other undamaged nerve cells to form neural pathways.
• This can be stimulated through rehabilitation- each time a behaviour is encouraged it activates the neural pathway and strengthens it.

Question 5

Recruitment of homologous areas

Answer 5

• This is when a homologous area of the brain on the opposite side is used to perform a specific task.

Question 6

Example of the recruitment of homologous areas…

Answer 6

• One example would be if Broca’s area was 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

Research to support the recruitment of homologous areas

Answer 7

• Lashley suggested that although each hemisphere has dominant functions, there is ‘equipotentiality’ for the other hemisphere to take on those roles.

Question 8

What is another adaptation of the brain that aids recovery?

Answer 8

• Denervation super sensitivity.

Question 9

When does denervation super sensitivity occur?

Answer 9

• Occurs when there is a loss of nerve supply (through damage or decay) and the neurons are unable to transmit their messages efficiently.

Question 10

What has to happen to adapt to the loss of nerve supply?

Answer 10

• The post-synaptic neuron adapts to increase its sensitivity to the neurochemical transmission at the synapse.
• This stimulates excitatory binding and makes the transmission of information more efficient.