Plasticity and Functional Recovery of the Brain

• Plasticity - the ability of the brain to change and adapt to new experiences and learning.
• Functional Recovery - A form of plasticity following damage through trauma, the brains ability to redistribute or transfer functions usually performed by a damaged area to undamaged areas. Quick and spontaneous recovery . It is not long term and may slow down so the patient may need rehab.
• Synaptic pruning - Where neural connections are lost due to lack of use and the frequently used connections are strengthened. 15,000 neural connections at 2-3 years old.
• Research into plasticity carried out by Davidson et al (2004) - Maguire (2000) found significantly more grey matter in the prosterior hippocampus than the matched control group in the brains of London taxi drivers. The cabbies have to take 'The Knowledge' test and there was more pronounced structural differences in those who have been in the job longer.
• Draganski (2006) also imaged brains of medical students 3 months before and after their final exams and found learning induced changes occured in the posterior hippocampus and parietal cortex presumably a result of learning.
• Doige (2007) suggested that brains can rewire and reorganise. New synaptic connections which are close to the area of damage are activated and unmasked for functioning to continue.
• Structural changes in the brain occur by axonal sprouting, denervation supersensitivity, recruitment of homologous areas.
• What is axonal sprouting in structural changes in the brain?

  The growth of new nerve endings which connect with undamaged nerve cells to form new neuronal pathways.
• What is denervation supersensitivity in structural changes in the brain?

  Occurs when axons that do a similar job are used to a higher level to compensate for the ones which are lost. but this can have negative consequences such as oversensitivity to pain.
• What is the recruitment of homologous areas on opposite sides?

  Specific tasks can still be performed using compensation from the other side of the brain.
• Give an example of recruitment of homologous areas on opposite sides?

  If Broca's area on the left were to be damaged, the right hemisphere of the brain would compensate by carrying out its functions for a period of time.