Neuroplasticity and Motor Learning Flashcards
1
Q
What is neuroplasticity
A
- the nervous system is plastic or modifiable
- ability of the brain to reorganize connections/wiring to optimize function & structure in response to internal/external stimuli
- Brain uses similar mechanisms during development, learning/memory, in response to injury/disease and in therapy
- Physiological basis of learning & memory and for recovery of function after injury
2
Q
What levels can neuroplasticity occur at
A
- Molecular
- Cellular
- Intercellular/synapse
- Network
- Systems
3
Q
Conceptual parallels between neuroplasticity and learning
A
- Neural modifiability: short term functional changes in efficacy of connections -> changes in synaptic efficiency -> persisting changes -> changes in synaptic connections -> long term structural changes
- Parallel continuum of learning: short term learning/memory -> short term changes -> persisting changes -> long term changes -> long term memory
4
Q
Common neuroplasticity concepts
A
- Critical period/window of neuroplastic mechanisms
- Similar critical period windows for development or for recovery after injury
- Positive/adaptive neuroplasticity versus maladaptive neuroplasticity
5
Q
Describe spontaneous versus activity induced neuroplasticity
A
- Spontaneous: some processes occur independent of external factors, guided by genetic/biochemical cues, mostly lead to initial improvements in function
- Activity induced: other processes are influenced by external input, sensory experience, motor experience, task training
6
Q
Response of CNS to injury by changing network/circuitry and/or cortical representation
A
- Strengthen parallel connections
- Unmask/activate silent connections
- Create new connections from cortex & alter cortical representation
7
Q
Response of CNS to injury through cortical mapping following peripheral lesions
A
- If silent/weak connections are spared (less severe injury): reactivation will occur by increasing responsiveness of existing previously masked/weak connections, cortical representation does not change much
- If injury involves larger body parts (receiving connections from a large area of cortex; ex. extremity amputation): cortical remapping happens by expansion of neighboring cortical areas
8
Q
Response of CNS to injury through cortical remapping following central lesions
A
- Reorganization in the affected hemisphere: recovery of function can happen with neighboring areas taking up lost function (ex. stroke in internal capsule, recovery of hand showed extension into face area of cortex); lesion in primary motor area can also result in activation of premotor & supplementary motor area
- Reorganization in the unaffected hemisphere (supplying uncrossed pathways): use of paretic hand activated both contralateral & ipsilateral motor areas
9
Q
Remapping of connections come from
A
- Adjacent areas
- Association areas
- Contralateral areas
10
Q
Cortical remapping patterns associated with good or poor functional recovery
A
- Bilateral activation was associated with poorer recovery compared to contralateral activation in case of more complete recovery
- Best recovery happens when cortical remapping looks like original ( areas closest to injury take up lost function
11
Q
Principles of neuroplasticity induced by activity or training
A
- Use it or lose it
- Use it and improve it
12
Q
Adaptive/positive neuroplasticity associated with therapy induced recovery
A
- In chronic stroke pts 3 wks of robot based PT pf paretic hand to improve grasp function was associated with 20 fold increase in contralateral sensorimotor cortex activation (use it or lose it); also increased laterally back towards lesioned side was associated with good functional gains
- Principle of specificity
13
Q
Principles of activity-dependent neuroplasticity
A
- Use it or lose it: neural circuits not actively engaged in task performance for an extended period of time start to degrade
- Use it and improve it: training can protect and/or improve networks that were impaired after injury
- Specificity: plasticity is specific to training of a particular new task or relearning a lost skill due to injury (skill training will improve skills while strength training will not improve skills)
- Intensity matters: training must be sufficiently intense to stimulate activity-dependent plasticity, needs to be progressively upgraded to match pt’s improving skills
- Repetition matters: repetition of newly learned task is required to induce long lasting changes
- Time matters: critical window of plasticity
- Salience matters: need to engage attention networks for experience-dependent plasticity to reorganize brain & improve skills
- Age matters: activity-dependent synaptic potentiation, synaptogenesis, cortical map reorganization all reduced with aging
- Transference/generalization: neuroplasticity in one circuit can promote plasticity in other related circuits
- Interference: plastic changes in a given circuit can impede induction of ew plasticity in same circuit ( may need to first unlearn compensatory techniques to learn the best way)
14
Q
Which principle is supported by the OPTIMAL theory and describe the OPTIMAL theory
A
- Salience matters
- OPTIMAL theory attempts to enhance expectancies, support patient autonomy, & promotes external focus of attention
15
Q
Describe motor learning
A
- a process of acquiring new abilities for skilled action
- cannot be measured directly but can be inferred indirectly from change in behavior/performance
- relatively permanent change in behavior
- theories of motor learning based ons stages of changing behavior
16
Q
Fitts and Posner’s 3 stage model of motor learning
A
- Cognitive stage (1st): trying out a variety of strategies, needs a lot of attention & conscious effort, makes many mistakes, improvements can be large
- Associative stage (2nd): makes less mistakes, practices more to refine the skill, needs less attention, improvements are slower/smaller
- Autonomous stage (3rd): performance mostly automatic, can divert attention to other tasks
17
Q
Bernstein’s 3 stage model of motor learning - mastering the degrees of freedom
A
- Novice, advanced, and expert stages (same as Fitts and Posner’s stages)
-Talks about releasing degrees of freedom at different joints with higher stages - Releasing degrees of freedom allows for more efficient & flexible movements according to task & environment demands
18
Q
Clinical application of Bernstein’s 3 stage model of motor learning
A
- Need to provide external support during early stages of learning to constrain degrees of freedom, support can be gradually released with improved performance
19
Q
Essential requirements for motor learning
A
- Acquisition of skill: successful performance of skill
- Retention of skill: successful demonstration of skill at a later time without practice during the intervening period
- Transfer of skill: successful application of the rules of movement of the skill to a related skill in a different environment
20
Q
When has a patient learned a skill
A
- a patient is said to have truly learnt a skill only if transfer or at least retention is demonstrated
- need to complete retention or transfer tests to assess motor learning
21
Q
Important ingredients to promote motor learning
A
- Practice: from principles of neuroplasticity (intensity & repetition matters); perfect practice makes perfect; practice patterns
- Feedback: feedback patterns = what type of feedback to provide, how often, timing
- Design treatment sessions with appropriate practice & feedback patterns for optimal motor learning
22
Q
Practice types
A
- Massed
- Distributed
- Constant: good for acquisition of skill
- Variable: good for retention and transfer of skills
- Random
- Blocked
- Whole: for continuous movement
- Part: for movements that can be broken into parts
- Mental
23
Q
Massed versus distributed practice
A
- Massed: all practice trials at once, amount of practice time is greater than amount of rest, may lead to fatigue
- Distributed: divide reps into smaller chunks, amount of rest between trials is equal or greater than the amount of time for the time
24
Q
Is massed or distributed practice better
A
- no evidence that one is consistently better but need to consider the patient’s impairments like strength, cognitive status, attention span, etc.
25
Constant versus variable practice
- Constant: practice of given task under constant/unchanging conditions, may improve acquisition of skill (use it to improve it)
- Variable: practice of a given task under variable conditions, better for retention & transfer of skill (transference principle)
26
Blocked versus serial versus random practice (ways to increase variable practice)
- Blocked: practice a single type task before going to the nest type (10 A's, 10 B's, 10 C's)
- Serial: ABC, ABC, ABC, and so on
- Random: practicing different types in random order (A, C, B, A, A, C, B, B, and so on)
27
Is blocked, serial, or random practice better for true motor learning
- Random variable practice is best for motor learning (true motor learning)
28
When is random practice useful
- in random practice initial performance is worse during acquisition stage but performance later is better
- Patient needs good cognitive abilities to benefit from random practice, not good for patients with cognitive impairment & might be hard to motivate patient since little initial success
29
Knowledge of results versus performance
- Knowledge of results: terminal feedback about the outcome of a movement in terms of achieving goal (telling the patient good job you did the task that was asked)
- Knowledge of performance: feedback relating to the movement quality/pattern used to achieve the goal (patient could have been faster, used more of their arms, directed toward of the patient completed the task, more qualitative)
30
Whole versus part practice
- Whole: practice the entire task together
- Part: practice of an individual impaired component(s) of a task from movement analysis of tasks, ultimately needs to practice the whole task to improve function
31
General guideline for whole versus part practice
- perform whole task for continuous tasks, & part practice followed by whole task for tasks that can be broken down into natural components
- breaking down linked components artificially might not be helpful or might even hinder learning
32
Describe mental practice
- performance of skill in one's imagination without physical action can produce positive effects on performance
- Trigger of neural circuits responsible for motor planning during mental practice (SMA test activated during mental practice - motor control physiology class)
- Can help with motor learning when physical practice is not yet possible
33
What kind of feedback is most effective for retention and transfer of skills
- Knowledge pf results is more effective than knowledge of performance
34
Types of feedback
- constant
- intermittent
- bandwidth
- fading
35
Describe constraint induced movement therapy
- Strongest research support
- Involves high intensity treatment daily for several hrs for 2-3 wks, after constraining the unaffected limb
- UE must retain some voluntary function on which to build
- Showed best results in subactue/chronic stroke (3-21 mo post stroke)
- Should not be considered for use with patients before 4 wks post stroke
36
Describe body weight supported treadmill training (BW-STT)
- Improved gait speed and balance comparable to traditional over-ground gait training
- Due to unweighting, BW-STT can provide a higher reps/volumes of training than over-ground training, so is more likely to induce neuroplasticity
37
Describe high intensity gait training (HIGT)
- Purpose is to improve locomotion function (walking speed and distance)
- Gait training at moderate to high intensity (65-85% HRmax/60-80% HRR) or based on RPE scale of 14-17
- Based on research using individuals who were able to walk w/o substantial assistance , may not apply to individuals with limited ambulatory function
38
Other interventions that have shown good motor learning of skills
- Mirror therapy with hemiparetic UE: patient moves the less affected UE while watching it move in mirror as though it were the more affected UE
- Bilateral arm training: performance of tasks with symmetrical patterns
- Mental practice
