functional recovery

Question 1

what is functional recovery (FR)?

Answer 1

• a form of plasticity
• the brain’s ability to redistribute or transfer functions usually performed by a damaged area to other undamaged areas following damage through trauma

Question 2

describe the process of recovery after brain trauma

Answer 2

• following physical injury, or other forms of trauma such as the experience of stroke, unaffected areas of the brain are often able to adapt and compensate for those areas that are damaged
• healthy brain areas may take over the functions of those areas that are damaged, destroyed or missing
• neuroscientists suggest that this process can occur quickly after trauma (spontaneous recovery) and slow down after several weeks or months
• at this point the individual may require rehabilitative therapy to further their recovery

Question 3

what happens in the brain during recovery?

Answer 3

• the brain is able to rewire and reorganise itself by forming new synaptic connections close to the area of damage
• secondary neural pathways that would not typically be used to carry out certain functions are activated to enable functioning to continue, often in the same way as before (doidge 2007)

Question 4

what structural changes in the brain support the process of brain recovery?

Answer 4

• axonal sprouting
• denervation supersensitivity
• recruitment of homologous areas on the opposite of the brain

Question 5

what is axonal sprouting?

Answer 5

the growth of new nerve endings which connect with other undamaged nerve cells to form new neuronal pathways

Question 6

what is denervation supersensitivity?

Answer 6

when axons that do a similar job become aroused to a higher level to compensate for the ones that are lost

Question 7

what is a consequence of denervation supersensitivity?

Answer 7

oversensitivity to messages such as pain

Question 8

what does recruitment of homologous areas on the opposite side of the brain mean?

Answer 8

• specific tasks can still be performed
• eg. 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 9

evaluation: real-world application

Answer 9

• understanding the processes involved in plasticity has contributed to the field of neurorehabilitation
• understanding that axonal growth is possible encourages new therapies to be tried
• eg. constraint-induced movement therapy is used with stroke patients whereby they repeatedly practise using the affected part of their body (such as an arm) while the unaffected arm is restrained
• this shows that research into functional recovery is useful as it helps medical professionals know when interventions need to be made

Question 10

evaluation: cognitive reserve

Answer 10

• level of education may influence recovery rates
• schneider et al. (2014) revealed that the more time people with a brain injury had spent in education (taken as an indication of their ‘cognitive reserve’) the greater their chances of disability free-recovery (DFR)
• 40% of those who achieved DFR had more than 16 years’ education compared to ~10% of those who had <12 years’ education
• this would imply that people with brain damage who had insufficient DFR are less likely to achieve a full recovery
• socioeconomic sensitivity needed

Question 11

evaluation: new research

Answer 11

• banerjee et al. (2014) treated people who had total anterior circulation stroke with stem cells
• all participants in this trial recovered compared to the more typical level of 4% recovery
• however, this study drew conclusions based on just 5 participants and had no control group, lowering the validity of the findings

Question 12

evaluation: the case of gabby giffords

Answer 12

• former US democratic politician who survived an assassination attempt in 2011 when she was shot in the head from point blank range
• doctors placed giffords into a waking coma
• within months, she had made astonishing progress
• with the aid of physical rehabilitation, she was able to walk under supervision with perfect control of her left arm and leg, and able to write with her left hand
• she could also read, understand and speak in short phrases
• doctors suggested that her progress would place her in the top 5% of people recovering from serious brain injury