Plasticity and Functional Recovery

Question 1

Define plasticity.

Answer 1

The brains ability to adapt and change as a result of learning and experience.

Question 2

Define synaptic pruning.

Answer 2

Rarely used connections in the brain are deleted as we age and frequently used connections are strengthened. Therefore, new neural connections are formed in response to demand in the brain.

Question 3

What is the benefit of synaptic pruning?

Answer 3

It enables lifelong plasticity which helps us to adapt and change as needed.

Question 4

How many men were studied in Maguire’s London taxi driver study?
How many men in the control group?

Answer 4

16 tested.
50 in the control group.

Question 5

What brain scanning technique did Maguire use to study her PPTs?

Answer 5

fMRI scans

Question 6

What was kept the same/different about the PPTs and the control group.

Answer 6

The men were of a similar age.
The control group were not taxi drivers.

Question 7

What did Maguire find from her study?’
What does this show about plasticity?

Answer 7

There was a larger volume of grey matter in the posterior hippocampus of the taxi drivers due to them requiring more knowledge of the roads.
This shows how the brain is able to adapt as needed, such as when a high volume of information is required to be remembered, therefore showing plasticity is a result of experience.

Question 8

Name a type of plasticity.

Answer 8

Functional recovery

Question 9

Describe the correlation between the size of the posterior hippocampus and the length of time spent as a taxi driver.

Answer 9

Positive correlation between the size of the posterior hippocampus and the length of time spent as a taxi driver.

Question 10

Define functional recovery.

Answer 10

A type of plasticity which causes the transfer of functions from damaged areas of the brain to undamaged areas. (from lobe to lobe or hemisphere to hemisphere).

Question 11

What is neural unmasking?

Answer 11

The activation of dormant synapses to compensate for areas of damage to the brain.

Question 12

What is axon sprouting?

Answer 12

New nerve endings grow and connect to other undamaged nerves to form new neuronal pathways.

Question 13

What is recruitment of homologous areas?

Answer 13

Similar areas in the opposite hemisphere become activated to carry out the function of the damaged area in the other hemisphere.

Question 13

What is denervation supersensitivity?

Answer 13

Nerves that perform a similar job to undamaged nerves become aroused to a higher level to compensate for the neurons that have been damaged.

Question 14

Explain the strength of plasticity being a lifelong ability. (Age)
Use the example from Bezzola, who found that plasticity still occurred in golfers aged 40-60.
Bezzola found that activity increased whereabouts in the brain?

Answer 14

Generally, plasticity reduces with age, however, Bezzola demonstrated how 40 hours of golf training caused changes in the neural representations of movement in PPTs aged 40-60. fMRI scans showed that activity increased in the motor cortex in novice golfers, compared to a control group. This suggests that neural representations are more efficient after training. This shows that neural plasticity continues through life.

Question 15

Explain the strength of there being research support from Danelli for plasticity. (Italian Boy case study)

Answer 15

The Italian Boy case study focuses on a boy who has his LH removed at age 2.5yrs. However, by the age of 17, his language and speech abilities compared to those of a healthy adult. This therefore demonstrates evidence for functional recovery as it suggests that his RH took over the functions of his LH. This is called recruitment of homologous areas. Therefore, provides evidence for plasticity and shows that the theory is valid.

Question 16

Explain the limitation of plasticity sometimes having negative consequences.
Use the example of phantom limb syndrome, experienced by amputees.

Answer 16

For example, 60-80% of amputees have been known to develop phantom limb syndrome, where a patient experiences pain/tingling in the limb that has been amputated. This is caused by cortical reorganisation in the somatosensory area. This means that the brains ability to adapt to damage may not always be beneficial.

Question 17

Explain the limitation that recovery rates by functional recovery may be influenced by the amount of education a person has received.
Use the example of research from Schneider ‘40% of people who made a disability free recovery had 16+ years in education’. Compare this to those who had 12 years in education.

Answer 17

Schneider found that the more time a person with brain damage had spent in education, the higher their chance of making a disability free recovery. 40% of those who had a disability free recovery had spent 16+ years in education whereas only 10% of people who had around 12 years in education made a disability free recovery. This would mean that people with less education are less likely to make a disability free recovery.