Plasticity & functional recovery of the brain after trauma

Question 1

What is brain plasticity?

Answer 1

The idea that the brain is like plastic how it changes & adapts as a result of experience and new learning

Question 2

When does the brain experience a rapid growth in synaptic connections?

Answer 2

During infancy it peaks at around 15000 synapses per neuron at the ages 2-3

Question 3

What happens to these synaptic connections as we age?

Answer 3

The rarely used connections are deleted whilst the frequently used ones are strengthened

Question 4

What were the original thoughts on brain plasticity & how has it changed after more recent research?

Answer 4

• Changes to the brain were restricted to the developing brain and an adult brain has a fixed structure & function
• More research suggests that neural connections can change at any time in life & new connections can form as a result of learning and experience

Question 5

What research did Mechelli et al do into plasticity?

Answer 5

He found a larger parietal cortex in bilingual people’s brain compared to monolingual person’s brain

Question 6

What happens to unaffected areas of the brain after a physical injury or other forms of trauma?

Answer 6

It is able to adapt and compensate for the damaged areas

Question 7

What is functional recovery?

Answer 7

A form of plasticity where the brain is able to redistribute or transfer functions usually performed by the damaged areas after damage through trauma

Question 8

What do neuroscientists suggest about the process of functional recovery?

Answer 8

It can happen quickly after trauma (spontaneous recovery) and then slow down after several weeks or months

Question 9

What happens in the brain after recovery?

Answer 9

• The brain is able to reorganise itself & form new synaptic connections close to the damaged area
• Secondary neural pathways that wouldn’t typically be used to carry out certain functions are activated to enable functioning to continue

Question 10

What are the 3 structural changes that happen in the brain during recovery?

Answer 10

Axon sprouting, reformation of blood vessels & recruitment of homologous areas on the opposite side of the brain to perform specific functions

Question 11

What is axon sprouting?

Answer 11

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

Question 12

What is reformation of blood vessels?

Answer 12

Damaged blood vessels are reformed to ensure the brain functions in affected areas

Question 13

Evaluation: Practical application

Answer 13

• Understanding processes in plasticity has contributed to neurorehabilitation
• Since spontaneous recovery slows down after several weeks/months a form of physical therapy may be required to maintain improvements in functioning
• Techniques may include movement therapy & electric stimulation of the brain to counter deficits in motor/cognitive functioning from a stroke for e.g.
• shows that the brain may be capable to ‘fix itself’ to an extent and further intervention needed for success

Question 14

Evaluation: Negative plasticity

Answer 14

• The brain’s ability to rewire itself may have negative behavioural consequences
• ## Prolonged drug use shown to result in poorer cognitive functioning & increased risk of dementia