Plasticity & Functional of the brain after trauma Flashcards
What is plasticity?
- This describes the brains tendency to change and adapt as a result of experience and new learning
What does Gopnik et al say about growth in brain at infancy?
- brain experiences rapid growth in the number of synaptic connections it has
- peaks at about 15,000 per neuron at 2-3 years of age
As we age what happens to our connections and what is this process known as?
- rarely-used connections are deleted & frequently-used connections are strengthened
- known as synaptic pruning
Outline Maguire et al’s research
& findings into Plasticity (2000)
- studied the brain of London taxi drivers who had taken ‘The Knowledge’ test
- found greater volume of grey matter in posterior hippocampus compared to control group
- longer time in job= more pronounced structural difference
What is the posteriori hippocampus associated with ?
- Development of spatial and navigational skills in humans and animals
What is functional recovery after trauma?
- form of plasticity
- which is the brains ability to redistribute/transfer functions usually performed by a damaged area(s) to other undamaged area(s)
What do neuroscientist suggest about the process of functional recovery?
- occurs quickly after trauma (spontaneous recovery)
- but slows down after several weeks or months so individual may require rehabilitative therapy to further their recovery
What happens to the brain during recovery?
- brain is able to rewire and reorganise itself by forming new synaptic connections
- secondary neural pathways are ‘unmasked’ to enable functioning to continue
What structural changes occur in the brain during recovery?
- Axon sprouting
- Denervation super sensitivity
- Recruitment of homologous areas on the opposite side of the brain -specific task can still be performed
What is Axonal sprouting?
- growth of new nerve endings which connect with other undamaged nerve cells to form neuronal pathways
What is denervation super sensitivity?
- occurs when axon that do a similar job become aroused to a higher level to compensate for the ones that are lost
What is a limitation of functional recovery (DFR)?
- level of education may influence recovery rates
- Schneider et al > the more time people with a brain injury had spent in education (taken as an indication of their cognitive reserve) > greater their chances were of disability free recovery
- 40% who achieved DFR had more than 16 years in ed compared to 10% who had less than 12 years in ed
- people with brain damage & less time ed are less likely to achieve full recovery (other variables involved)
What is a strength of plasticity and functional recovery?
- real life application
- research into plasticity & functional recovery has led to development of neurorehabilitation
- uses movement therapy & electrical stimulation of brain to counter the deficits in motor & cognitive functions following accidents or injuries e.g. strokes
- research useful as it helps medical professionals know when to intervene to help improve cognitive functions of people suffering with injuries > external validity
What is a strength of plasticity?
research support
- Maguire et al >studied the brain of London taxi drivers who had taken ‘The Knowledge’ test
- found that the posteriori hippocampi volume correlated positively with their experiences as a taxi driver & also found a greater volume of grey matter in posterior hippocampus compared to control group
- implies experiences cause plasticity
What is a counterpoint to the strength of plasticity?
- limitation of Maguires study is that we cannot be sure whether the differences is due to ‘The knowledge’ as the taxis drivers were not tested before becoming taxi drivers
- thus a clear change in the structures of the brain as a result of their experiences cannot be concluded
- it may be that the drivers had a larger hippocampus before becoming taxi drivers
- cause & effect relationship between experience and changes in the brain cannot be established
