Plasticity and Functional Recovery of the Brain After Trauma

Question 1

What is brain plasticity?

Answer 1

The brains ability to change and adapt (functionally and physically) as a result of or in reaction to the environment, experience and new learning

Question 2

What is synaptogenesis?

Answer 2

Where many new synapses are formed. This can occur throughout life but during infancy there’s an explosion of synaptic formation (known as exuberant synaptogenesis)

Question 3

What is neurogenesis?

Answer 3

When new neurons are grown. In infancy this is responsible for populating the growing brain with neurons, but also occurs in adulthood

Question 4

What is synaptic pruning?

Answer 4

Otherwise known as axon pruning. The process of synapse elimination that typically happens between early childhood and the onset of puberty. However, this has also been shown to occur to a lesser extent in adulthood

Question 5

Computer gaming - Kuhn et al study

Answer 5

Kuhn et al 2014 illustrated the potential benefits of playing super Mario for 2 months playing for 30 minutes a day. They found significant increases in areas of the brain (e.g., the hippocampus, the cortex and the cerebellum) responsible for key behaviours such as working memory, planning and motor performance

Question 6

Taxi driving study - Maguire et al 2000

Answer 6

studied the brains of London taxi drivers using an MRI and found significantly more grey matter in the posterior hippocampus than in the matched control group. This part of the brain is associated with the development of spatial and navigational skills in humans and other animals. As part of their training, they must take a complex test called ‘the knowledge’ which assesses the recall of the city sheets and possible routes. It is also worth noting that the longer they had been doing the job the more pronounced the structural difference (positive correlation)

Question 7

Astronauts study - Seidler et al 2017

Answer 7

Seidler et al 2017 conducted a study on astronauts, they had MRI’s before and after space missions which revealed that astronauts’ brains compress and expand during space flight, according to a University of Michigan study. They found large regions of grey matter volume decreases which could be related to redistribution of cerebrospinal fluid in space. Seidler said “gravity is not available to pull fluids down in the body, resulting in so called puffy face in space. This may result in a shift of brain position or compression” This is an extreme example of neuroplasticity in the brain because you’re in a microgravity environment 24 hours a day. This likely reflects brain plasticity associated with “learning how to move in microgravity”

Question 8

What are the 3 types of brain plasticity?

Answer 8

Synaptogenesis, axon pruning and neurogenesis

Question 9

What are the 3 types of functional recovery?

Answer 9

Neural regeneration, neural unmasking and neural reorganisation

Question 10

What is neural regeneration?

Answer 10

Also known as axon sprouting, occurs when new nerve endings grow and connect with undamaged areas. This can compensate for damaged areas and enable the recovery lost function

Question 11

What is neural unmasking?

Answer 11

Occurs when ‘dormant synapses’ are opened and become functional. Can occur when a surrounding brain area becomes damaged as the rate of input to these dormant synapses would increase opening connections to regions of the brain that are not normally activated and allowing gradual development of new structures

Question 12

What is neural reorganisation

Answer 12

Occurs when the brain transfers function from the damaged area to the undamaged sections of the brain. For example, if Broca’s area in the left hemisphere was more damaged then an area on the right hemisphere may take over.

Question 13

Factors affecting functional recovery:

Answer 13

Age - children have the best ability to recover, then young adults
Gender - women have a higher likelihood to recover from brain damage
Rehabilitative therapy - Focused effort results in improvement

Question 14

Danelli (2013) study

Answer 14

investigated a case of an Italian Boy (EB) who had most of his left hemisphere removed aged 2 ½ to remove a tumour. With intensive therapy, his right hemisphere was able to take over almost all the functioning (language, speech etc.) that would normally have been done by the left. This is largely because EB’s brain would have shown maximal plasticity

Question 15

Positive evaluation of plasticity and functional recovery - research to support

Answer 15

There is research to support the idea that the brain can recover (at least to some extent) from significant trauma. For example, Danelli (2013) investigated a case of an Italian boy (EB) who had most of his left hemisphere removed aged 2 ½ to remove a tumour. With intensive therapy, his right hemisphere was able to take over almost all the functioning (language, speech etc) that would normally have been done by the left. This is largely because EB’s brain would have shown maximal plasticity. This implies, the brain is more than capable at reorganising itself through functional recovery and supports the concept of plasticity at a young age

Question 16

Positive evaluation of plasticity and functional recovery - practical applications

Answer 16

This research will inevitably lead to very useful PRACTICAL APPLICATIONS. Newer research into the role of early onset dementia and ways of treating this promote the use of video games. Gazzeley et al 2013 developed a game called NEURORACER that can be prescribed to adults to help preserve their cognitive functioning. Hence this research suggests plasticity can have enormous and novel uses to help society.

Question 17

Negative evaluation of plasticity and functional recovery - case study, populational validity

Answer 17

However, this research is a case study and therefore lacks population validity. The research into EB only relates to a male Italian patient so the finding can be considered androcentric so is potentially not representative of females/ Also these results may not represent people from diverse cultures (so ethnocentric too) and this may not represent people of different ages either. This implies support for plasticity and functional recovery if case study based, my not be generalisable so may cast doubt on the idea of the plasticity and functional recovery of the brain.

Question 18

Negative evaluation of plasticity and functional recovery - not universal, several factors

Answer 18

Recovery from brain trauma is not universal and there are several factors that may influence and individual’s ability to recover. One identified factor is age, with most research indicating that functional plasticity reduces with age. For example, Teubar (1975) found a negative correlation with age and recovery when investigating soldiers’ recovery from brain injury. 60% of those under 20 year – huge improvement, whereas 20% over 25 similar improvements. This could mean that plasticity of the brain is clearly affected by age so it is not a case that all individuals would benefit from functional plasticity.