Evaluation of Brain Plasticity and Functional Recovery

• strengths

  • research support from animal studies for neural plasticity
  • research support from humans for neural plasticity
  • support from animal studies for functional recovery
• research support from animal studies for neural plasticity 


  Kempermann et al (1998)- found evidence of new neurons in the brains of rats housed in complex environments compared to rats housed in laboratory cages. the rats housed in the complex environment= an increase in neurons in the hippocampus (associated with the ability to navigate from one location to another)
• research support from animal studies for neural plasticity COUNTER ARGUMENT 


  can't generalise animals to humans as humans are complex
• research support from humans for neural plasticity 


  Maguire et al. (2000) London Cabbies and Davidson et al. (2004) Tibetan Monks

  • both uses a control group- allows us to conclude that there is a significant difference
  • use of scientific, objective measurements (MRI and electrodes fitted to brain)
  • both attempted to study a real world phenonema- high ecological validity
• support from animal studies for functional recovery 


  Hubel and Wiesel (1963)- sewed one eye of a kitten shut and analysed the brains cortical responses. it was found that the area of the visual cortex associated with the shut eye was not idle (as predicted) but continued to process information from the open eye
• support from animal studies for functional recovery COUNTER ARGUMENT

  • ethical issues
  • animals can't be applied to more complex humans
• limitations

  • negative plasticity
  • plasticity changes with age
  • level of education may influence functional recovery
• negative plasticity

  • the brain's ability to rewire itself can sometimes have maladaptive behavioural consequences
  • it was found that prolonged use of marijuana resulted in poorer cognitive functioning as well as increased risk of dementia later in life
  • phantom limb syndrome- 60-80% of amputees have been known to develop this. they continue to experience sensations in the missing limb as if it were still there. these sensations are usually unpleasant and are thought to be due to the cortical reorginisation in the somatosensory cortex that occurs as a result of limb loss
• plasticity changes with age 


  age is a confounding variable which affects the plasticity of the brain. functional plasticity tends to reduce with age. according to this view the only option following traumatic brain injury beyond childhood is to develop compensatory behavioural strategies to work around the deficit (such as seeking social support for developing strategies to deal with cognitive deficits)
• plasticity changes with age COUNTER ARGUMENT 


  some studies have shown that even abilities commonly thought to be fixed in childhood can still be modified in adults with intense retraining. researchers showed that 40 hours of golf training in 40-60 year olds produces changes in the neural representation of movement -> suggests that neural plasticity is evident in all ages and not just young people
• level of education may influence functional recovery 


  the level of education may influence functional recovery rates. Schneider et al. (2014)- the more time people with a brain injury had spent in education (taken as an indication of their cognitive reserve) the greater their chances of disability free recovery (DFR). 40% of those who had more than 16 years' education compared to 10% of those who had less than 12 years' education. implies that people with brain damage who had insufficient DFR are less likely to achieve a full recovery.