Plasticity & Functional of the brain after trauma

Question 1

What is plasticity?

Answer 1

This describes the brains tendency to change and adapt as a result of experience and new learning

Question 2

What does Gopnik et al say about growth in brain at infancy?

Answer 2

-brain experiences rapid growth in the number of synaptic connections it has
-peaks at about 15,000 per neuron at 2-3 years of age

Question 3

As we age what happens to our connections and what is this process known as ?

Answer 3

.rarely-used connections are deleted
.frequently-used connections are strengthened
known as synaptic pruning

Question 4

Outline Maguire et al’s research into Plasticity (2000)

Answer 4

-studied the brain of London taxi drivers= had taken ‘The Knowledge’ test
- found greater volume of grey matter in posterior hippocampus compared to control group
- longer time in job= more pronounced structural difference

Question 5

What is the posteriori hippocampus associated with ?

Answer 5

Development of spatial and navigational skills in humans and animals

Question 6

What is functional recovery after trauma?

Answer 6

• form of plasticity
  -brains ability to redistribute/transfer functions usually performed by a damaged area(s) to other undamaged area(s)

Question 7

What do neuroscientist suggest about the process of functional recovery?

Answer 7

-occurs quickly after trauma (spontaneous recovery)
-slows down after several weeks or months so individual may require rehabilitative therapy to further their recovery

Question 8

What happens to the brain during recovery?

Answer 8

-brain is able to rewire and reorganise itself by forming new synaptic connections

-secondary neural pathways not typically used are ‘unmasked’ to enable functioning to continue

Question 9

What structural changes occur in the brain during recovery?

Answer 9

Axon sprouting -growth of new nerve endings which connect with other undamaged nerve cells to form neuronal pathways

Denervation supersensitivity-axons that do a similar job become aroused to higher level to compensate for the ones that are lost

Recruitment of homologous areas on the opposite side of the brain -specific task can still be performed

Question 10

Explain why plasticity may have negative behavioural consequences (Median et al)

Answer 10

Medina et al - brain’s adaptation to prolonged drug use leads to poorer cognitive functioning in later life as well as increased risk of dementia

Question 11

Explain why plasticity may have negative behavioural consequences (Ramachandran & Hirstein)

Answer 11

-60-80% of amputees develop phantom limb syndrome (sensation in limb as if it was still there)
-painful, unpleasant experience
-due to cortical reorganisation in the somatosensory cortex that occurs as a result of limb loss

Question 12

What is a limitation of FR ( DFR)?

Answer 12

-level of education may influence recovery rates
-Schneider et al revealed that the more time people with a brain injury had spent in education (taken as an indication of their cognitive reserve)
the greater their chances were of disability free recovery
-40% who achieved DFR had more than 16 years in ed compared to 10% who had less than 12 years in ed
-people with insufficient DFR less likely to achieve full recovery (other variables involved)

Question 13

strength of plasticity and functional recovery?

Answer 13

-real life application
research into plasticity & functional recovery has led to development of neurorehabilitation which uses movement therapy & electrical stimulation of brain to counter the deficits in motor & cognitive functions following accidents or injuries
-research useful as it helps medical professionals know when to intervenes