Plasticity & Functional Recovery of the Brain

Question 1

What is brain plasticity?

Answer 1

• As we grow our brain grows in synaptic connections peaking at around 15,000
• When we rarely use the synapses we have grown they are deleted
• Ones used more frequently are strengthened this is known as Synaptic Pruning
• Research suggests that at any time in life existing neural connections can change and be formed this is known as Plasticity

Question 2

What are 2 strengths of Plasticity?

Answer 2

Video Game Research
- A study compared a control group with video game training group who trained for 2 months at least 30 minutes/day
- They found significant increase in grey matter in various brain areas including the cortex, hippocampus and cerebellum
- This was not evident in the control group that did not play super Mario

Researchers concluded that video game training had resulted in new synaptic connections in the brain involved in spatial navigation, planning, memory and motor skills

Taxi Drivers Plasticity
- Maguire studied the brains of London Taxi drivers and found significantly more volume of grey matter in the posterior hippocampus than in a matched control group
- Taxi drivers had to take ‘the knowledge’ which makes them learn every street and how to get from A to B

The longer they had been on the job and more they had driven showed more pronounced structural differences

Question 3

What is functional recovery?

Answer 3

• Following physically injury or strokes, unaffected areas of the brain are able to adapt and compensate for those areas that are damaged
• The brain effectively rewires itself over time with healthy brain areas taking over functions that have been lost
• Patients may require further rehabilitative therapy to further their recovery

Question 4

What are methods of brain recovery?

Answer 4

• Regenerative developments in brain functions arise from the brain plasticity
• Brain can rewire new synaptic connections close to area of damage to find new routes to complete the same functions
• This is done by either, Neuronal Unmasking or Stem Cells

Question 5

What is Neuronal Unmasking?

Answer 5

• Dormant synapses are synaptic connections that exist anatomically but hither functions are blocked
• Under normal circumstances these synapses may be ineffective because the rate or neural input to them is too low for them to be activated
• If a brain suffers damage then these synapses could open (unmask) and allow connections to regions of the brain that are not normally activated

Question 6

What can Stem cells do? (Super-swing)

Answer 6

• Stem cells are unspecialised cells that have the potential to rise to different cells types that cary out different functions
• Stem cells can form into cells to provide treatments for brain damage caused by injury or neurodegenerative disorders
  1) Stem cells could be implanted into the brain to directly replace dead or dying cells
  2) Stem cells could secrete growth factors that rescue injured cells
  3) Working cells could be transplanted to an injured area of the brain

Question 7

What are 3 strengths of Functional Recovery?

Answer 7

Animal Studies
- A study provided evidence for the role of stem cells from brain injury
- Randomly assigned rats with traumatic brain injury to 1 of 2 groups
- 1 group received transplanted stem cells into injured brain
- Other group received no stem cells to injured brain
- 3 months post brain injury, stem cell rats showed development of neuron like cells
- Not seen in the control group with no stem cells
Supporting the role of functional recovery in brain repair

Intelligence linked with increased functional recovery
- Study found that patients with the equivalent of a college education are 7x more likely to be disability free and almost fully recover after a traumatic brain injury
- A study including 769 brain injury patients: 214 had disability free recovery (DFR)
- 39.2% of patients with 16+ education had DFR
- 30.8% with 12-15 years of education
- 9.7% with less than 12 years
Concluded that cognitive reserve could be a factor in neural adaptation during recovery

Decreases with age but still possible
- Commonly accepted that plasticity and recovery decreases with age but if has been found that this can still occur in adults the same as younger adults and children
Concluded that it is still much more common in children but still possible in adults