Brain Plasticity and Recovery

What is ‘plasticity’?

The brain adapts in both its function and structure as a result of a change in the environment. These changes could be due to damage, or to meet the cognitive demands of learning new skills

What are the 4 reasons for plasticity?

• Learning new skills

• A result of developmental changes

• Response to direct trauma to area of the brain

• Response to indirect effects of damage such as brain swelling or bleeding (from stroke)

What is functional recovery?

The functions that were performed by areas of the brain that are lost (neuronal cell death) or damaged are performed by undamaged areas of the brain (functional reorganisation)

What is synaptic pruning?

The brain removes unused or weak connections (synapses) between neurones to become more efficient. Eg if a child doesn’t practice playing piano, the brain might prune the synapses related to that skill

What is axonal sprouting?

Existing neurones growing new axons to connect to adjacent neurones. This then causes neural regeneration which is the growth of new neuronal cells

What is denervation supersensitivity?

To compensate for the loss of axons in a pathway, the remaining axons become more sensitive. (More likely to fire). This can result in side effects such as pain

What are the 3 factors affecting functional recovery?

Age = Children have the best ability to recover, then young adults

Gender = Women are more able to recover from brain damage

Rehabilitative Therapy = Focused effort results in improvement

What is constraint induced therapy?

Stopping patients from using coping strategies (like body language for communication or using undamaged limbs or tasks) makes them improve via functional reorganisation

AO3 - Maguire (2000)

Structural MRI brain scans of 16 male taxi drivers were compared to the brain scans of 16 matched (age, gender) non taxi driver controls. The posterior hippocampi in the London taxi drivers were found to be significantly larger than the controls. Also, the size of the posterior hippocampi was positively correlated with the amount of time working as a taxi driver. This suggests the physical structure of the brain is plastic and able to reconfigure itself to better adapt to psychological demands, in this case to improve memory formation

AO3 - Danelli (2013)

Case study of 14 year old EB. At the age of 2 and a half EB had a hemispherectomy of the left side of his brain to remove a tumour. This removed the language centres of Broca’s and Wernicke’s areas. Immediately after surgery EB had lost all language ability (aphasia). However, after 2 years of recovery EB recovered his language ability. Even without his left hemisphere EB developed normally aside from some dyslexia like symptoms. Researchers noted FMRI scans showed the right hemisphere followed a ‘left like blueprint’ for language. This research suggests the brain adapts and recovers after significant damage, especially in early life, with the right hemisphere taking roles usually performed by the left

AO3 - Practical benefits

Research on brain plasticity and functional recovery has practical benefits. It has been useful in rehabilitative therapy, helping people return to their lives and productive work, ultimately benefiting the wider economy

AO3 - Mathias (2015)

Metanalysis demonstrated IQ and educational background are positively correlated with better outcomes after traumatic brain injury, suggesting some individuals have a greater cognitive reserve, helping in recovery

AO3 - Real world application

Research on individuals recovering lost function can help psychologists understand more about the functions of regions of the brain that were initially damaged