Plasticity and functional recovery of the brain after trauma

Question 1

what is brain plasticity?

Answer 1

• ability to change throughout life
• infancy the brain has rapid growth in the number of synaptic connections
• has double the amount that the adult brain
• new neural connections are made due to new demands on the brain

Question 2

what is synaptic pruning?

Answer 2

• rarely used connections are deleted
• frequently used connections are strengthened

Question 3

research into plasticity: London taxi drivers

Answer 3

• Maguire et al. found more grey matter in posterior hippocampus in taxi drivers than control group
• area of the brain is in control of spatial and navigational skills
• the longer they had had the job, the more pronounced the structural difference

Question 4

research into plasticity evaluation limitation: Negative plasticity

Answer 4

-brains adaptation due to prolonged drug use, led to worse cognitive functioning and increased risk of dementia
- 60-80% of amputees have phantom limb syndrome, due to cortical reorganisation in the somatosensory cortex

Question 5

research into plasticity evaluation: strength age and plasticity

Answer 5

• general plasticity reduces with age
• Bezzola et al. showed 40 hours of golf training produced changes in the neural representations of movements in participants aged 40-60
• using fMRI observed increase in motor activity cortex in novice golfers rather than control group

Question 6

Functional recovery

Answer 6

• plasticity following damage through trauma
• brain ability to redistribute or transfer functions usually performed by a damaged area to a non damaged area

Question 7

functional recovery: after brain trauma

Answer 7

• healthy brain areas take over the functions of areas that were damaged or missing
• this process can occur quickly then slow down after weeks or months
• may then need rehab therapy

Question 8

what happens in the brain during recovery?

Answer 8

• forms new synaptic connections close to the area of damage
• secondary neural pathways are activated or unmasked to enable functioning to continue, in the same way as before

Question 9

structural changes in the brain

Answer 9

• axonal sprouting
• denervation supersensitivity
• recruitment of the homologous

Question 10

what is axonal sprouting?

Answer 10

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

Question 11

what is denervation supersensitivity ?

Answer 11

• occurs when the axons that do a similar job become aroused to a higher level to compensate for the ones that were lost
• Although can be negative when they become oversensitive to pain

Question 12

what is the recruitment of the homologous?

Answer 12

• areas on the opposite side of the brain
• specific tasks can still be performed
• if brocas area was damaged on the left the right side would carry out its equivalent functions
• after a while functionality may shift back to the left side

Question 13

Functional recover evaluation: strength real-world application

Answer 13

• understanding plasticity has contributed to the field of neurorehabilitation
• encourages new therapies
• research into functional recovery is useful as it helps medical professionals know when interventions need to be made

Question 14

Functional recovery evaluation: limitation cognitive reserve

Answer 14

• the level of education may affect recovery rates
• Schneider et al. said the more time people with brain injuries had spent in education the greater their chances of disability free recovery (DFR)
• 40% who had DFR had 16 years + of education compared to 10% who had less than 12 years of education