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
& findings into Plasticity (2000)

Answer 4

• studied the brain of London taxi drivers who 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
• which is the 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)
• but 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

What is the limitation that plasticity may have negative behavioural consequences?

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
• researchers also found that 60-80% of amputees develop phantom limb syndrome (sensation in limb as if it was still there)> painful/unpleasant experience
• said to be due to cortical reorganisation in the somatosensory cortex that occurs as a result of limb loss

Question 11

What is a limitation of functional recovery (DFR)?

Answer 11

• level of education may influence recovery rates
• Schneider et al > the more time people with a brain injury had spent in education (taken as an indication of their cognitive reserve) > 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 12

What is a strength of plasticity and functional recovery?

Answer 12

• real life application
• research into plasticity & functional recovery has led to development of neurorehabilitation >
• 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 intervene