Brain Plasticity

Question 1

Brain Plasticity Definition

Answer 1

-During infancy, the brain experiences a rapid growth in the number of synaptic connections it has.
-As we age, rarely used connections are deleted and frequently used connections are strengthened- synaptic pruning
-Originally thought that these changes were restricted to only happen in childhood. However, recent research suggests that at any time in life existing neural connections can change and new connections formed as a result of learning and experience

Question 2

Research into plasticity (Maguire et al 2000)

Answer 2

Maguire et al 2000 studied the brains of London taxi drivers and found significantly more volume of grey matter in the hippocampus than in a matched control group

-This part of the brain is associated with the development of spatial and navigational skills in humans.

-London cab drivers have to complete “The Knowledge” which assesses their recall of the city streets and possible routes. It was found that they longer they were in the job, the more pronounced the difference in their brain was

Question 3

Research into plasticity (Draganski et al)

Answer 3

-Imaged the brains of medical students three months before and after their final exams
-Learning-induced changed were seen to have occurred in the hippocampus and the parietal cortex due to the exam .

Question 4

Functional recovery of the brain after trauma

Answer 4

-After injury, unaffected areas of the brain are often able to adapt and compensate for those areas that are damaged
-The functional recovery that many occur in the brain after trauma is another example of neural plasticity.
-Healthy brain areas may take over the functions of those areas that are damaged, destroyed or even missing,
-Suggested it can happen quickly after trauma

Question 5

What happens in the brain during recovery?

Answer 5

-The brain is able to rewire itself and reorganise itself by forming new synaptic connections close to the area of damage
-Secondary neural pathways that are not usually used are activated to enable functioning to continue

Structural Changes:
-Axonal Sprouting= growth of new nerve endings which connect undamaged nerve cells to form new neuronal pathways
-Reformation of blood vessels
-Recruitment of homologous areas on the opposite side of the brain to perform specific tasks

Question 6

A03- Age and Plasticity

Answer 6

P=It is well thought that functional plasticity reduces with age.
E=However, Bezzola et al demonstrated how 40 hours of golf training produced changes in the brain in ppts aged 40-60
The golfers demonstrated reduced motor cortex activity compared to a control group
E=This suggests that the motor cortex became more efficient after training. Therefore, this shows that neural plasticity does continue throughout lifespan

Question 7

A03- Support from animal studies

Answer 7

P=There is evidence of neuroplasticity from animal studies.
E=Research involved sewing one eye of a kitten shut and analysing the brain’s cortical responses
E=It was found that the area of the visual cortex associated with the shut eye was not idle but continued to process info from the open eye.

I+D
Ethical Issues
Generalisability

Question 8

A03-Negative Plasticity

Answer 8

P=The way the brain rewires itself can sometimes have a negative behavioural consequence
E= 60-80% of amputees have been known to develop phantom limb syndrome- the continued experience of sensations in the missing limb as if it was still there
E=These sensations are usually unpleasant, painful and are thought to be due to cortical reorganisation in the somatosensory cortex that occurs as a result of limb loss

I+D
Biological Reductionism