plasticity and functional recovery after trauma

Question 1

what is brain plasticity?

Answer 1

• brains ability to grow and adapt to new functions and learning
• synaptic connections that are rarely used are lost and ones frequently used are strengthened
• brain not fixed after critical period

Question 2

+ what was Maguire’s research on plasticity?

Answer 2

• Maguire (00) studied brains of London taxi drivers who have to take 3 year knowledge test of London roads
• found more grey matter in posterior hippocampus (associated with spatial and navigation skills)
• positive correlation between length of job and amount of structural difference
  (correlation not causation)

Question 3

+ what is Draganski’s research on plasticity?

Answer 3

• brain image of medical students 3 months before and after final exam
• changes in posterior hippocampus and parietal cortex most likely due to the exam
  (correlation not causation)

Question 4

what is functional recovery of the brain after trauma?

Answer 4

• brain ability to transfer function from damaged area to damaged area
• occurs quickly after trauma and then slows down after weeks/ months (rehabilitative therapy required)

Question 5

how does the formation of new synaptic connections help functional recovery?

Answer 5

• new connections form near the damaged area and create secondary neural pathways not typically used for that function (Doidge 07)

Question 6

what structural changes can occur in the brain during functional recovery?

Answer 6

• axonal sprouting - new nerve ending connect to undamaged cells
• reformation of blood vessels
• recruitment of similar (homologous) areas of the brain in the opposite hemisphere

Question 7

+ Case study - Giffords

Answer 7

• gabby giffords a politician shot in head in 2011
• put in waking coma, then within months with rehabilitation she had control of her left arm and leg and can write with left hand (right hemisphere not as damaged)
• • however she was highly educated and it was a unique experience

Question 8

+ practical application

Answer 8

• plasticity and recovery slows down after several weeks so rehabilitative therapy needed
• research shows movement and therapy and electrical stimulation needed for best recovery

Question 9

• negative plasticity

Answer 9

• Medina (07) said things like drugs can cause poorer cognitive function and increase risk of dementia later in life
• 60-80% of amputees suffer phantom limb syndrome where sensation of missing limb in painful and unpleasant