Chapter 25 - Recovery, Plasticity, and Rehab

Question 1

What is recovery of function

Answer 1

process where the brain regains lost abilities after injury, but can range from complete restoration to partial improvement

Question 2

What is compensation

Answer 2

finding new ways to perform tasks, rather than restoring the lost function itself

Question 3

Who decides if recovery has occurred

Answer 3

patient, physician, spouse, employer, WEC, insurance?

depends on who is the right person to ask

ex. family thought injured patient showed great recovery and Kolb’s disagreed

Question 4

When does recovery occur

Answer 4

common view = over by 6-12 months (wrong)

not a specific timeline!

can occur for a long time after

Question 5

What does the portrait case tell us

Answer 5

15 year old that had right hemisphere stroke. (due to rib breaking) had some motor recovery but remained severely impaired in left hand

23 years later started swimming and began to feel movement in his left hand

Question 6

What are the levels of analysis in plasticity

Answer 6

1. behaviour
2. neural imaging
3. cortical maps (invasive and noninvasive)
4. physiology (LPT)
5. synaptic organization
6. mitotic activity
7. molecular structure

Question 7

cortical maps

Answer 7

can see in monkeys the digit and wrist movement during tasks
specific experiences produce specific changes

Question 8

physiological level

Answer 8

stimulation of neuron and get responses.
now blast the cell, now records a new average response
result in changes to dendritic and more synapses

Question 9

mitotic activity

Answer 9

exercise increases generation of new neurons and increased blood flow

Question 10

What are the 10 principles of brain plasticity

Answer 10

1. common to all NSs: plasticity is a universal trait
2. can be analyzed at multiple levels
3. 2 general types of plasticity = experience expectant (during development) and experience-dependent (brain changes that are already present) both change from experience
4. even similar behaviours can lead to different plastic changes and different regions
5. experience-dependent changes interact = past experiences like stress can influence future experiences
6. varies with age - younger brains are more flexible
7. time-dependent - some changes are permanent and others are short lived
8. linked to experience’s relevance
9. intensity and frequency influence - more intense and frequent experiences lead to greater/faster brain changes
10. maladaptive - can have negative effects

Question 11

experience expectant vs experience dependent plasticity

Answer 11

expectant = something that changes due to experience that you were predicting/expecting
dependent = changes that occur due to experience, but were not expecting (ex. taking a neuro class when you were born)

Question 12

What is metaplasticity

Answer 12

refers to the flexibility of synaptic plasticity and the brains ability to change how it adapts and learns based on past experiences

Question 13

What is maladaptive plasticity

Answer 13

when brain changes lead to negative outcomes
due to drug use, motor disorders, hyperconnectivity, conditions

Question 14

What is the key structural changes is where

Answer 14

at the synapse

Question 15

What is learned nonuse

Answer 15

people learn to not use where they had an injury
ex. have a stroke and can’t use left hand, so learn how to live without using it (negative outcome because can’t recover if don’t use it)

Question 16

What are 3 early postinjury treatments

Answer 16

1. tPA to unblock vessels in ischemic stroke (a block)
2. neuroprotectants (drug reduces body temperature in rats, we are too big for it to work,) protect neurons from damage after injury, reduce secondary damage, minimize further harm
3. thrombectomy (procedure to remove a blood clot from the brain, restoring blood flow)

Question 17

What factors influence recovery of function

Answer 17

age (young), handedness (left-handed = less lateralized), sex (female), intelligence (higher intelligence), personality, small lesion

more connections

Question 18

what assumptions regarding cortical organization are challenged by the concept of recovery

Answer 18

brain functions are not rigidly fixed to specific locations
cortical maps can remap after injury

Question 19

What mechanisms might be responsible for recovery

Answer 19

neuroplasticity - form new connections and reorganize existing ones
cortical reorganization - undamaged areas take over
neurogenesis - new neurons generated
compensatory mechanisms

Question 20

What evidence is there that recovery (compensation) occurs

Answer 20

neuroimaging studies = show other areas take over
animal models = research shows animals form new connections and areas of the brain compensate
rehabilitation
neuroplasticity
genetic and pharmacological evidence - boost neurotrophic factors and reduce inflammation to promote recovery

Question 21

what types of therapies might prove beneficial

Answer 21

electrical stimulation (vagus nerve stimulation), cognitive rehabilitation (targeted exercises), tactile stimulation (massage), growth factors and stem cells, pharmacological therapies (drugs), physiotherapy, musical and behaviour therapies

Question 22

what physiological events are associated with brain damage

Answer 22

cellular injury and death
excitotoxicity - excessive release of glutamate to overstimulate neurons that damage cells
inflammation - worsening damage
oxidative stress - injury causes production of reactive oxygen species

Question 23

what does the nudo experiment show

Answer 23

cortical plasticity, of motor function recovery after brain injury after monkeys experienced sensorimotor cortex lesion

cortex reorganized and adjacent areas took over motor functions, rehabilitation significantly increased cortical reorganization from repetitive motor training that underwent practice with impaired limbs, can recover motor abilities through plasticity

Question 24

how does age relate to recovery

Answer 24

younger individuals recovery better due to higher neuroplasticity and cell regeneration

older brain = reduced plasticity and cognitive reserve

Question 25

outline the ways in which imaging studies show plasticity after injury

Answer 25

get feedback about which areas of the brain need to work in order to do so, or when something works they can see that on the imaging and tell them to do it again

Question 26

what are the issues surrounding the use of stem cells for recovery

Answer 26

ethical concerns, safety (tumor formation and immune rejection), effectiveness (not integrate well into existing brain), legal issues (lengthy approval process), cost

Question 27

outline the therapeutic approaches to brain recovery

Answer 27

behavioural therapy
pharmacological therapy
brain stimulation
rt-fMRI
brain tissue transplants and stem-cell induction
diet as building blocks

Question 28

What is constraint-induced behavioural therapy

Answer 28

therapy to improve motor function after brain injury

healthy limb is immobilized to prevent use, encouraged to use impaired limb for daily tasks, gradually increase difficulty of task

Question 29

what is CamSense and how does it work to enhance memory

Answer 29

strategy to promote neural plasticity to reorganize and form new neural connections

sensing brain activity and stimulating specific neural regions

Question 30

give an example of a pharmacological therapy

Answer 30

stimulants (amphetamine, nicotine, etc).
cause the brain to change, nicotine stimulates brain to change, and will do and see those changes

Question 31

what is NoGo-A? What type of treatment is used to block the actions of it

Answer 31

antibody that blocks NoGo-A, it will enhance plasticity (because NoGo-A limits neuronal regeneration)

pharmacological treatment

will increase in number of spines and is underlying reason to recover