Finally getting to Part 3 of @ACLStudyDay - integrating motor learning into #ACL rehab, with @Dusty_Grooms !

First: required pre-reading:
1) https://www.jospt.org/doi/10.2519/jospt.2015.4986
2) https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6548061/

Thread of my notes from the lectures to follow .....

The brain functions as a hierarchy of networks that promote movement. Everything eventually links to the motor cortex.

Environmental context influences how well a patient looks in different environments.

Neuroplasticity results in:
- incr cortical area assoc w/ the skill (the more you do a skill, the more your brain dedicates to it)
- new neuron support cells to facilitate skill
- improves neural efficiency (as ability incr, neural activity req decr for more complex tasks)

ACL Injury results in:
- altered sensory info (somatosensory) into primary sensory cortex
- brain tries to maintain neural drive to motor cortex --> gets missing primary sensory info (visual, vestibular)

ACL injury causes:
1) mechanical instability
2) mechanoreceptor destruction
3) inflammation/edema

Creates spinal inhibition + motor neuron disruption = disrupted afferent signal

Results in arthrogenic muscle inhibition. Need CNS re-organization to get pre-injury motor control.

Exam of brain activation pattern:
- people w/ high risk landing strategy have add'l brain activation patterns
- these patterns are activated in people AFTER injury (premotor planning, cognitive region activity)

MAYBE can address to reduce initial AND post-injury risk?

Next topic: Motor Control and Motor Learning

Motor performance = ability to perform a specific motor task

Motor learning = transfer of trained, rehearsed mov't patterns/skill to AUTOMATICA and robust to unanticipated events

Motor performance can be TEMPORARILY affected by motivation, stress, attention, fatigue ... but these are temporary.

Motor performance shouldn't be equated 100% with motor learning.

For highly complex tasks, want pt to be initially very focused to get good performance.

Motor learning:
"The ability to generalize learned motor skills enables us to modify our movement strategy in novel situations."

Requires:
1) goal-directed motor task
2) repeated practice/experience
3) feedback (variable, goal-directed)

Retention test = measures how well can perform the task after temporary practice effects have worn off

Transfer test = measures if the learned skill transfers from one condition to another

More terms!

Explicit learning = can recall the steps or processes of the motor task
** concentrated in fewer brain areas

Implicit learning = you can't exactly describe what you did to do the task
** highly distributed across multiple brain regions

Stages of Motor Learning:
1) Cognitive: Skill acquisition. Lots of mistakes, high performance variability
2) Associative: start to consolidate/develop skills - slow improvement in performance, variability decr
3) Autonomous: indpt, mastered motor skill - adapt to new situations

So how do you apply this clinically to test for motor learning?

Example: Dual cognitive task. Have them do the task counting backwards by 7, for ex. See if the motor performance is the same.

Errors can ENHANCE learning.

Practice variability leads to optimal learning, better ability to transfer motor skills from one situation to another (novel).

(Obviously, millions of errors not ideal, but some errors, that can be corrected, are safe for adaptation)

Error correction:
Start with motor plan, do action, get feedback (ankle inverts and hurts), know you have an error --> either correct immediately or update motor plan for next time.

Brain determines if predicted outcome equals what happens - helps w/ error detection/correction

CLINICAL APPLICATIONS!

Repetition is needed but repetition of the same task isn't going to help in the long term. Require problem-solving through error detection/correction.

Scheduling practice in more of a distributed fashion (eg, circuit training) can help with improving motor planning/error detection.

If you mass practice (eg, do same thing over &over), performance improves but the motor planning doesn't transfer. May be impt for fatigue tho

Feedback:
- knowledge of performance: tell them exactly what to do
- knowledge of results: get the outcome to happen

Usually in PT, we want performance to be same as results (eg, good mov't pattern during motor skill). Initially start w/ explicit feedback (PT gives feedback), progress to implicit feedback (they know what did right/wrong)

Consider autonomy support:
- ask the patient what they want to do in a session (give choices, all which meet your goals)
- ask the patient when they want feedback or how often

Enhanced Expectancies: (for pts w/ high physical ability but low confidence)

"Wow you're doing better than others at this stage / peer matched controls"

"I know you will be successful with this task"

Change attentional focus:

Ex: during squat
- internal: keep knees from moving inward
- external: aim knees towards the cones
- internal: don't lose balance
- external: keep bar level

**Internal feedback helps people move better right away but not ability in novel tasks

Summary:
- pt should be active participant in planning, problem-solving of mov'ts
- practice allows some errors to enhance learning

As therapist, identify:
- goal of task
- what it should look like
- what feedback is ESSENTIAL vs DETRIMENTAL to learning
- where the pt's attention should be during practice