Plasticity and functional recovery after brain trauma Flashcards
What is plasticity?
Neuroplasticity or cortical remapping describes the brains tendency to change and adapt as a result of experience and new learning
What is functional recovery?
A form of plasticity. Following damage through trauma, it is the brains ability to redistribute or transfer functions usually performed by the damaged area to other undamaged areas
How does the brain appear to be plastic?
It has the ability to change throughout a lifetime - the brain experiences rapid change and growth in number of synaptic connections during infancy (peaking at around 15,00 aged 2-3 - twice as many as adult brain
What happens to connections as we age?
Rarely used connections are deleted and those frequently used are strengthened - this synaptic pruning
What was previously thought about the adult brain?
That it was fixed and static in terms of function and structure however recent research found that neural connections can change at any time
What was Maguire et al’s research into plasticity?
He studied the brains of London taxi drivers and found significantly more volume of grey matter in the posterior hippocampus than in the matched control group
What is it that the posterior hippocampus is linked with?
Navigation and spatial skills
What do taxi drivers have to do as part of their driving?
‘The Knowledge’ - which assesses their ability to navigate streets including all possible routes - it appears this process strengthens this area in the brain as the longer they had been in the job the more pronounced the structural differences
What did Draganski et al find about plasticity?
Imaged the brains of medical students three months before their exams and after their final exam and found that structural changes appeared in the posterior hippocampus and parietal cortex
What did Mechelli et al find about plasticity?
Found there was a larger parietal cortex in the brains of people who were bilingual compared to matched monolingual controls
After physical injury and trauma such as strokes what are unaffected areas able to do?
Adapt and compensate
When does functional recovery occur?
Quickly after the trauma (spontaneous recovery) and then will slow down after several weeks or months and at this point the patient may require rehabilitative therapy
How does a brain recover?
It is able to rewire and reorganise itself by forming new synaptic connections close to the area of damage. Secondary neural pathways are activated or unmasked to enable functioning to continue - this is supported by structural changes in the brain (e.g. axonal sprouting)
What is axonal sprouting?
The growth of nerve endings which connect with the other undamaged nerve cells to form new neuronal pathways
What two other things does the brain do to recover?
Reformation of blood vessels
Recruitment of homologous (similar) areas on the opposite side of the brain to perform specific tasks
