plasticity + functional recovery

• what do we mean when one says the brain is 'plastic?'

  the brain's ability to change and adapt as a result of experience
• what is synaptic pruning?

  as we age, rarely used connections are deleted and frequently used connections are strengthened
• what is meant by the term 'use it or lose it'

  synaptic pruning will occur if we do not frequently use our connections, or we will lose them
• how does 'you can't teach an old dog new tricks' support old ideas about changes in plasticity over the lifespan?

  changes are limited to childhood
• what has recent research told us about plasticity over the lifespan?

  neural connections can be changed or reformed at any time because of learning and experience
• name 2 studies that used brain scans to show that plasticity continues throughout adulthood

  maguire et al (2000)

  draganski et al (2006)
• what was the procedure of maguire et al (2000) study?


  investigated london cab drivers brains as part of their training, they took a complex test and wanted to see what affect that had
• what were the findings of maguire et al (2000) study?

  the volume of neurone cell bodies in the posterior hippocampus (linked with the development of spatial + navigational skills) of london cab drivers was much greater than in a matched control group
• what was the conclusion of maguire et al (2000) study?

  the learning experience seems to alter the structure of the drivers' brains. the longer they had been in the job, the more pronounced the structural difference was, which suggests plasticity continues throughout adulthood
• what was the procedure of draganski et al (2006) study?

  investigated the brains of medical students three months before and three months after their final exams
• what were the findings of draganski et al (2006) study?

  changes had occurred in the posterior hippocampus (and parietal cortex) when scanned before and after their final exam
• what was the conclusion of draganski et al (2006) study?

  learning for their exams had changed their brain structure, which suggests that plasticity continues throughout adulthood
• what is meant by functional recovery of brain after trauma?

  after a traumatic experience, healthy and unaffected areas of the brain take over the functions of areas that have been damaged
• what is neural plasticity and how does it lead to functional recovery?

  the brains ability to regain functions which were lost due to injury/illness. the healthy brain areas take over the functions of damaged/missing areas
• what is axonal sprouting and how does it lead to functional recovery?

  the growth of new nerve endings which connect with other undamaged cells to form new neuronal pathways
• what is recruitment of homologous areas?

  recruitment of similar areas on the opposite side of the brain to perform certain tasks
• what is a positive evaluation point for plasticity and functional recovery?

  IRL application - movement therapies and electrical stimulations have been developed so we understand that the brain can heal itself up to a certain point but further intervention can make this more successful, contributing to neurorehabilitation

  animal studies support - researchers sowed a kitten's eye shut and found the area of visual cortex associated with the shut eye switched to processing info from the open eye, supporting idea that loss of function leads to compensatory activity in brain as valid
• what is a negative evaluation point for plasticity and functional recovery?

  lacks generalisability - neural plasticity is not the same for everyone and there are individual differences in the brains ability to recognise itself and factors like education influence this. a researcher had found the more time brain injury patients spent in education, the greater the chance of a disability-free recovery

  lacks generalisability + unethical - the kitten is not protected from harm but also as an animal, its findings cannot be generalised to humans
• what is a negative evaluation point for plasticity?

  age and plasticity is complex - functional plasticity tends to reduce with age as it is most likely to reorganise during childhood as it adapts to new experiences and learning but maguire and draganski's research contradicts this, so it is difficult to draw valid conclusions