BIO: Plasticity and functional recovery

Question 1

define neuroplasticity

Answer 1

the ability to change and adapt in response to experience (plasticity)

Question 2

background info on evolution of neuroplasticity:

Answer 2

• humans are born with small incomplete brains
• connections are made after new experiences- very quickly in children

Question 3

How do Pathways work:

Answer 3

• pathways that are used more will grow thicker and develop more branches
• pathways that are not often used are destroyed

Question 4

what can plasticity help us recover from?

Answer 4

injury

Question 5

what are the two types of plasticity?

Answer 5

1. structural plasticity (growth)
2. functional plasticity (recovery)

Question 6

define structural plasticity (growth)

Answer 6

experiences cause a change to brain structure

Question 7

define functional plasticity (recovery)

Answer 7

localised functions move from a damaged region to an undamaged region after injury

Question 8

Structural plasticity (growth+change) -Process:

Answer 8

Stage 1. Synaptic Pruning- axons that aren’t used will weaken and eventually be lost
Stage 2. Neural unmasking- a hormone; nerve growth factor (NGF) encourages growth
Stage 3. Axonal Sprouting- chemicals called neurotrophins sustain and encourage growth
Stage 4. Synaptic Connection- the new connection makes its parent network stronger

Question 9

Functional recovery - Process:

Answer 9

Stage 1. Axon damage (axotomy) e.g. stroke- axon is severed due to injury (dendrites would just regrow)
Stage 2. Axonal sprouting- new axon/dendrite growth towards target
Stage 3. Blood vessels re-form (capillaries and glial cells)- ‘Glial’ cells wrap around capillaries, support blood-brain barrier
Stage 4. recruitment of homologous (similar) areas- usually on the opposite hemisphere

Question 10

Jody Miller study:

Answer 10

• had epileptic seizures
• removed right hemisphere of her brain
• she was fine and could learn to walk and move because of plasticity

Question 11

Evaluation 1: (applications)

Answer 11

P- Applications
E- healthcare, mindfulness (strengthens connections) anxiety treatments
E- Furthermore, case of Jody Miller
L- ecological validity

Question 12

Evaluation 2: (Supporting evidence)

Answer 12

P- supporting evidence
E- Macguire et. al, (2000) found hippocampal volume increases when working memory was used intensely due to structural plasticity
E- Schneider et. al. (2014) found recovery from traumatic brain injury was positively correlated with years of education
L- Lots of external validity

Question 13

Evaluation 3: (Nature vs Nurture)

Answer 13

P- Nature vs Nurture
E- Shows that behavior affects the biological structure of your brain (can improve nature by nurturing your brain