A01 Plasticity/Functional Recovery Of The Brain After Trauma

• Brain plasticity


  Brain appears to have the ability to change throughout life. During infancy, the brain experiences a rapid growth in the number of synaptic connections peaking at 15,000 synapses per neuron at age 2-3 years. This equates to double the number of adult synapses in the adult brain
• Synaptic prunning


  The elimination of neurons as the result of nonuse or lack of stimulation as we age
• Oringinal theories


  Thought that changes only occur in childhood and adult brain havingmoved beyond a critical point, remained fixed. Recent research however suggests the brian always changes due to learning and experiences (plasticity)
• Research into plasticity


  Maguire et al studied the brains of London taxi drivers and compared them against a control group and used a complex test called the 'Knowledge' as drivers needed to know the London streets thoroughly.
• Maguire et al findings


  They found significantly more volume of grey matter in the posterior hippocampus in the taxi drivers than in a matched control group. This part of the brain is associated with the development of spatial and navigational skills in humans and other animals. This difference shows plasticity.
• Draganski et al


  Imaged brains of medical students 3 months before and after final exams. Learning changes occurred in posterior hippocampus and parietal cortex as a result of the exam
• Mechelli et al


  Found a larger parietal cortex in the brains of people who were bilingual compared to matched monolingual controls
• Functional recovery of the brain after trauma


  When damage occurs, the unaffected areas of the brain are often able to adapt and compensate for the damaged areas. Functional recovery is another example of neural plasticity.
• Process of recovery


  Healthy brain areas take over the functions of those areas that are damaged. Neurologists suggest spontaneous recovery occurs where the brain immediately works in recovery yet slows down after several weeks/months. Therefore, the individual may need rehabilitative therapy for further recovery
• What happens in the brain during recovery?

  The brain is able to rewire and reorganise itself by forming new synaptic connections close to the area of damage. Secondary neural pathways that wouldn't typically be used to execute functions are activated to enable continued function.This process is supported by axonal sprouting, reformation of blood vessels and recruitment of similar areas.
• Axonal sprouting


  The growth of new nerve endings which connect with other undamaged nerve cells to form new neuronal pathways