Plasticity and functional recovery of the brain after trauma Flashcards
what is brain plasticity?
- 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
what is synaptic pruning?
- rarely used connections are deleted
- frequently used connections are strengthened
research into plasticity: London taxi drivers
- 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
research into plasticity evaluation limitation: Negative plasticity
-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
research into plasticity evaluation: strength age and plasticity
- 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
Functional recovery
- plasticity following damage through trauma
- brain ability to redistribute or transfer functions usually performed by a damaged area to a non damaged area
functional recovery: after brain trauma
- 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
what happens in the brain during recovery?
- 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
structural changes in the brain
- axonal sprouting
- denervation supersensitivity
- recruitment of the homologous
what is axonal sprouting?
- the growth of new nerve endings which connect with other undamaged nerve cells to form new neuronal pathways
what is denervation supersensitivity ?
- 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
what is the recruitment of the homologous?
- 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
Functional recover evaluation: strength real-world application
- 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
Functional recovery evaluation: limitation cognitive reserve
- 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