Progressive Gait Training: Motor Learning Strategies and the Research

This forty-five minute webinar presented on April 12th, 2018, gives an overview of current research on motor learning, discussing motor skill acquisition through practice, feedback, and prompt reduction. It concludes with a demonstration of Rifton Pacer features that provide dynamic support and progressively faded physical prompting.

Webinar Slides

References: Gait Training

References: Motor Learning in Pediatric Therapy

See the webinar Q&A here.

Webinar Transcript

Slides 1 – 4

Welcome to our gait training webinar. Thank you for joining us. This webinar will be discussing motor learning and motor learning research. So a very important consideration when we think about learning is to differentiate between acquiring the skill initially, then retaining that skill over time and finally being able to generalize that skill to different situations, adapting it to new tasks. Learning is all of these.

Slides 5 – 6

We can think of it as the stages of learning. So where we would have acquiring a skill initially, you may not always be accurate, movement might be slower, but then with fluency you are going to become more proficient and achieving the skill without direction and instruction. Finally, generalizing and adapting is continuously learning to apply the skill in novel situations. As we consider the skills themselves we have discrete skills, (clear beginning and end) such as sitting to standing, more complex skills, and then finally continuous skills which would be walking. Walking is considered a continuous skill.

Slide 7

Now there’s also the environmental context. So in a closed situation it is very predictable and stable, but with an open situation, you cannot actually effectively plan your entire movement in advance because you may be adapting to a changing environment, such as walking through a crowded cafeteria. This is a continuum with a semi-predictable environment somewhere in between.

Slides 8 – 9

Think about the feedback or the amount of support or prompting that occurs when teaching a new skill. We will want to systemically fade down the amount of support from full physical support to perhaps modeling or demonstrating and finally verbal input until the child is able to perform their skill completely and independently. This would be a most-to-least prompting. Similarly we have least-to-most, and this may be in the later stages of learning where we allow a child to attempt their best effort and only provide verbal input for tactile and physical support when absolutely needed.

Slides 10 – 14

So how do our interventions impact learning? We need to look at both practice and feedback. When we think of practice we are thinking about what is practiced, when it is practiced, and how it is practiced. And we will look at specific motor learning terms related to each of these areas. The first is specificity. The motor learning is going to relate very distinctly to what specifically is practiced. And this is borne out by research where the limb involved in the motor task, in the motor skill that is practiced, there is actually a correlation to changes and neuroplasticity in the brain of the corresponding area. This research reviewed by Moreau also emphasizes that point where it is gait training that affects gait training outcomes. Strengthening does not. Salience discusses the importance and relevance to the person of the task that they are doing. And this is why goal setting is important, because we will have that motivation and that attention to task when it matters to the individual.

Slides 15 – 24

This brings us to thinking about when a skill is practiced. No one disputes that practice has a positive effect on learning. Other variables can be manipulated to benefit learning, but the sheer amount of practice is important. Those familiar with Malcolm Gladwell’s book, “The Outliers” are familiar with the idea that it takes ten-thousand hours of practice to separate a violin virtuoso from a mere violin player. As we think about these sheer hours of practice, is there anything we can do to speed learning? That is where these motor learning strategies come in. When we look at children - typically developing children learning to walk, it is thousands of steps in a day. However, they aren’t all done at once. They are broken up and performed intermittently between periods of not walking. Also, practice is performed in a variety of contexts. This contributes to learning. So practice scheduling matters. That’s the discussion of massed versus distributive practice. Mass practice has more time spent in practice than in rest, distributive practice has more time in rest periods than in practice. The motor learning theory here is that rest not only allows for restoration from fatigue and renewal of your motivation, but also something happens in the brain. There is a consolidation of learning that is occurring during that break. This is a landmark systematic review, most of the research up until that point was on continuous practice but this established that distributive practice does have good outcomes in terms of retention. Over all, more time will be required for distributive practice. For example walking for five minutes, resting for ten minutes, you would need to continue for one and a half hours to get thirty minutes of practice total. But we can also look at this as practicing walking for ten minutes at three times in the day, or for fifteen minutes twice a day.

Now for discrete tasks the effect of massed versus distributive practice is less clear. The 2013 references are actually able adults doing a specifically instructed sport-related motor skill, but we are seeing more current research suggesting that for a discrete skill, mass practice can be appropriate.

Slides 25 – 29

That brings us to how does the practice occur. The first point is that variability is very important for retention and learning. Variability can be a matter of the task variation, as well as the context or environment. Constant practice is when the parameters are essentially unchanged. You can imagine taking steps on a treadmill for example. Variable practice means that there are different parameters within that one practice session. The way we do this might be block practice where we do one skill drilling it over and over before moving onto another skill within that practice session. And then we have random practice where you are interspersing a number of different skills randomly within that same practice session. We find that acquisition is better with blocked practice. But skill retention and transfer is better with random practice. So what improves immediate performance is not necessarily what improves retention over the long run.

Slides 30 – 31

The open diamond is the random practice. The black rectangle is blocked practice. With early practice the movement time is shorter, showing better performance with blocked. And for intermediate practice the difference is not as extreme. But then in terms of retention for the individual who practiced with random variable practice, their long term retention was improved and they could perform that skill better. So variable practice improves that transfer, that generalization, that adaptation, that long-term outcome. Even though the variability produces more performance errors during the initial learning.

Slides 32 – 33

Contextual interference is a word that discusses this random practice. It is that interference resulting from practicing these various skills within the same session. So alternating from one task to another and then back demands that constant restructuring of performance with slightly different solutions each time. This problem solving is valuable for long-term retention and generalization. So, that high CI (Contextual Interference) is resulting in better learning and the low CI is actually inhibiting performance for those novel task demands. The Prado research in 2017 was in fact with individuals with cerebral palsy performing a computer maze and the random practice led to better performance for transfer tests.

Slides 34 – 36

For children, the effects of blocked versus random practice is less clear. Zipp did a research project with children who are performing a Frisbee toss. Interestingly, blocked practice in that case did show a benefit for retention and transfer. So it suggests that the task difficulty and the child’s stage of learning do need to be taken into consideration as we teach motor skills. So for simpler tasks it seems that we have random practice as our optimal option, whereas for highest difficulty tasks, random practice is less optimal. For beginners the lower level of CI is more appropriate and for highly skilled individuals random practice is more effective.

Slides 37 – 45

Difficulty is our next topic. If we are requiring the learner to repeat the problem solving process rather than just repeating a movement, the practice is difficult, effortful, but learning is achieved. We need to consider the skill level of the individual, the complexity of the task, the task environment as well as the assistance provided. And as these researchers point out, we need to look beyond the challenge of the task itself to the ability of the learner and the environmental context. So they differentiate between the functional task difficulty related to the ability level of the person and the environment context as compared to nominal task difficulty which is the characteristics of the task itself. Our optimal level of challenge will result in learning. On the one hand, increasing task difficulty increases learning potential. At the same time we have to realize that it is expected to decrease performance. So we want to maximize learning and yet minimize detriment to performance during practice. This tells us that in order to make progress we have to be comfortable with effort and we will only be growing and learning when we are uncomfortable. MOVE has a great way of putting this: just manageable difficulty. Challenging skill development but not making it too difficult.

Slides 46 – 48

Which brings us to part-whole practice, learning parts of a motor skill and then integrating it to practice the whole task, versus learning the entire skill as a whole. There are benefits to both types of practice and the field of motor learning offers considerations for the use of part and whole practice during motor skill acquisition. Naylor and Briggs gave us their hypothesis of task complexity and organization. Schmidt and Wrisburg - looking at skill classification.

Slides 49 – 51

Let’s think about the hypothesis of task complexity and organization. How many components are involved in the task? Walking would be considered a continuous skill, so that is low complexity. High complexity might be transitioning from lying to standing. In terms of the organization are the components interrelated or interdependent? Walking involves both upper and lower extremity reciprocal swing and multiple joint involvement. It would be considered high organization. Naylor and Briggs’ recommendation is that whole practice is appropriate for a skill that is low in complexity and high in organization. Walking is indeed a skill where whole practice is relevant.

Slide 52

And this has been borne out by research where we have had stroke patients balancing on their hemiparetic limb. The results after balance training did show that patients bore weight more symmetrically but did not in fact increase the single limb stance on the paretic limb when walking.

Slides 53 – 55

Now, there are advantages to part practice in certain circumstances when we need to simplify the skill or promote early success for motivation or focus practice on our problem components. So as we consider Part-Task versus Whole-Task, again we need to look at the task, the learner and the environment. And that brings us to the skill classification approach of Schmidt and Wrisburg where they consider the task, the environment, and also the person and their attention demands. The attention demands of the motor performance, the attention demands of the concurrent cognitive tasks for example and whether we can simplify and then increase challenge as learning progresses.

Slides 56 – 58

So learning parts of the task maybe helpful during the early stages, but whole task practice results in overall better movement quality and must be our final goal. As we segment those segments to practice we want to recombine them into sequencing. For example the practice from sit to stand and then taking a few steps following on that. Fractionalization is appropriate when it is a dual task. We practice each part and then recombine.  Or, we may simplify and then increase the challenge. Fontana’s meta-analysis has concluded that more research is necessary to find which practice, whole or part, is most ideal.

Slide 59

Transfer appropriate training is so important. Moving beyond the part and whole practice to utilizing the skill in the environments that are in the context where it will be used.

Slides 60 – 63

So we can think of it as first practicing those most needed components, then the whole task, and finally taking that task and generalizing it into natural environments: Walking to the office to take the attendance, walking to a vending machine, combining walking with saying hello to favorite people in the hallway without stopping the gait. This brings us to the feedback segment of our presentation. If we think about feedback, first we attempt the skill, then we receive feedback, and then we’re adapting that approach to attempt a skill again with more success. Explicit learning is conscious. We can verbally describe those critical parameters of the task, consciously finding solutions. Implicit learning is occurring on a subconscious level and is a response to the environmental demands. So implicit learning is actually possible regardless of age, intelligence or motor ability and it’s seen as appropriate for children with cerebral palsy or altered movement dynamics.

Slides 64 – 66

Our feedback may be intrinsic, verbal feedback, modeling or physical guidance and this rings back to our most-to-least and least-to- most prompting slide. If we think about intrinsic feedback versus the explicit feedback (of verbal and modeling input) – so the intrinsic feedback is inherent in the sensory motor system and is not conscious, promoting implicit learning.

Slides 67 – 68

So the intrinsic feedback is not under conscious control and this implicit learning can be facilitated by structuring the tasks and the environment, supporting those effective movement patterns. We want to limit verbal feedback because that would contribute to more conscious learning. This will enhance implicit motor learning, it involves the external focus of attention and practicing the whole skill in entirety.

Slide 69

Extrinsic feedback on the other hand augments and supplements the intrinsic feedback. This is related to conscious learning. This compares to extrinsic feedback involving verbal instructions, or visual observational learning with modeling and/or physical guidance and this is supplementing the intrinsic feedback. How essential is this? Well, the outcome with the augmented feedback is definitely going to depend on the type or the difficulty of the skill, the person’s ability, and their stage of learning, but if done correctly it can help speed the process of learning. So we are going to take some time to look at the research on extrinsic feedback.

Slides 70 – 74

We can think about the type or the content of the feedback as well as the amount and timing of the feedback. This influences outcome. Content may be focusing on the process of the movement, whether in feedback or in instruction. It may be focusing on the outcome of the movement, it may focus on error, it may focus on success. Timing is important – whether we are giving that feedback consistently or less often, when we give the feedback and whether that is the summary, or fading it over time. Or only providing it at a certain bandwidth. So all these approaches have motor learning terms and we will just look at the research for each of these.

Slides 75 – 78

Knowledge of performance pertains to the movement pattern. Knowledge of results is in regards to the outcome of the movement, in terms of the environmental goal. So both forms of feedback have their place. This 2018 study by Bishop was with children with attention deficit hyperactivity disorder, practicing an underhand toss for corn hole. Knowledge of performance feedback maybe helpful when a specific movement is required for a skill, or the movement is more complex. This may be prescriptive where we tell a person what to do to prevent or correct errors, or it may be descriptive, where we are simply describing and encouraging the learner to find their own solutions. So prescriptive is appropriate right at the beginning but descriptive later on will encourage learners to find their own solutions.

Slide 79

Knowledge of results on the other hand is focusing on the outcome of performing a skill in terms of achieving the goal and does not describe the process or movement involved. There is a lot more research on knowledge of results(KR) feedback.

Slide 80

Knowledge of a result when given verbally can be helpful when the task-intrinsic or knowledge of performance feedback isn’t being processed well, and can help promote certainty.

Slides 81 – 82

That brings us to the concept of internal versus external focus. The internal focus has more to do with the movement of the body part whereas the external focus is looking at the concrete environmental outcome of the movement. We can think, for example, of a child who attempts to walk straight by evening out the stride length versus the child who walks along aside a wall and avoids veering into the wall.

Slide 83

The internal focus results in conscious control over one’s movement and may actually constrain the motor system. Whereas the external focus allows the motor system to naturally self-organize with the abilities that are available and inherent to the person, resulting in more effective learning without that conscious control.

Slides 84 – 85

Errors versus correct. What is better, to point out errors or to praise positive performance? Let’s first think about implicit learning. This is where the feedback is occurring intrinsically through your sensory system. For the initial stages of practice we may do better to constrain errors and rather promote good movement for gaining a skill.

Slide 86

Explicit learning on the other hand is that verbal conscious feedback. We do know that providing error information will improve skills. However, providing positive information is motivating. So we do need a combination in order to promote what is known as a growth mind set.

Slides 87 – 88

Motivational praise can be done in more than one way. This study was with ten year old children performing a throwing task for accuracy. Both groups received truthful feedback on the accuracy of their throw, but one group received bogus positive praise complementing their performances as being above average and better than their peers. Those that received that additional praise actually performed better in retention trials.

Slides 89 – 90

And we can also look at that feedback as either focusing on the child themselves as a great player, soccer player, or on the task as something that is acquirable. And in the outcomes of the research the children who received non-generic feedback focusing more on the task than on the child themselves, performed better on the retention test.

Slides 91 – 93

Now we will look at the amount and the timing of the feedback. Findings show that more frequent feedback interferes with learning. And this Hemayattalab study was with children with cerebral palsy ages five to seventeen performing a dart throw. The group that had one hundred percent knowledge of results feedback for all their trials did not perform as well for long term learning. This may be because consistent feedback promotes a reliance on that feedback and discourages the individual’s ability to detect the error intrinsically and this is borne out with research on adults.

Slide 94

Interestingly, these findings are borne out more with adult research whereas with children, more feedback actually results in better learning when the task is difficult or complex. So the frequency of feedback will depend on the task difficulty as well as on the age and skill level of the learner. There may be times when more feedback is better.

Slides 95 – 98

Now let’s think about when the feedback is given. The problem with concurrent feedback or feedback given immediately at completion or right after the movement is that it may improve performance during the practice, but it is not better for learning retention. Again we’re distracting from that task intrinsic feedback and that important implicit learning that is needed. So the only times when this type of feedback may be appropriate would be again when it’s facilitating learning of critical features of the task where task-intrinsic feedback is difficult to process. But we don’t want to promote dependence on the feedback. Instantaneous knowledge of results degrades learning whereas when we wait a few seconds we have better results with feedback. When it’s given too soon it interferes with internal processing, but when it is delayed it can facilitate that processing.

Slides 99 – 100

Think about the time between the end of the practice and the provided feedback. We want that delay. Also think about the time between the feedback given and the beginning of the next practice attempt. Don’t rush that. This post-cKR interval is also important. That’s when the learner is engaging in planning and processing that feedback to implement their next attempt plan of action.

Slides 101 – 103

When we think about producing feedback there are ways to do this. Summary, faded and bandwidth. Summary is giving that feedback after a certain merge trials which can be averaged and for simple skills we can do those as longer summaries less frequently. For more complex skills we will probably want to provide shorter summaries and more frequently.

Slides 104 – 105

Fading the feedback is reducing the feedback frequency, even to the point of only providing when requested by the learner. As an example giving feedback for fifty percent of the trials and reducing that to when it becomes self-selected. And in our case it may be a matter of a child turning and looking to us to indicate that they would like feedback.

Slides 106 – 107

Bandwidth is providing feedback only if the errors are outside a certain range of correctness and we may decide to give no feedback within that band. So bandwidth feedback is when the knowledge of results is given only if the outcome of the movement is more than a certain amount in error. And the important thing here is as we individualize it and set that standard perhaps the bandwidth size doesn’t matter so much as the fact that the learner knows when they will be receiving less feedback.

Slide 108

Here we can see it visually, the child’s performance across the top of the graph there, summary feedback given at intervals, faded feedback given at first more frequently and then less frequently, and bandwidth feedback only when the child is outside a certain margin of error.

Slides 109 – 110

So we have covered all these terms with motor learning. We will just finish up with modeling and physical guidance and that will bring us to our product demo.

Slides 111 – 115

Observational learning is when demonstration may provide information that otherwise would be hard to grasp through verbal input. And that can be useful in the case of children with disabilities particularly when a specific movement is needed or for more complex tasks where that observational learning is helpful. Modeling or demonstration is less effective when you are trying to refine an existing movement pattern or when the goal outcome is not actually dependent on one way of doing it. And again demonstration can be self-selected, or self-controlled. We want to consider how we can couple that modeling with a verbal focus on an outcome goal. The main thing being that our learner is encouraged to find novel solutions to the problem at hand and is not prescribed something that may not be effective given their particular motor abilities.

Slides 116 – 117

Peer modeling can be useful, hearing the feedback given to another learning model, or observing a variety of other models. But let’s remember demonstration is not necessarily more effective than verbal feedback, certainly not as effective as physical practice and we can always allow the learner to first perform physical practice and then observe the demonstration or alternate between. Physical guidance may be manual guidance to provide correct positioning, physical support is giving stability or constraining movement to reduce the degrees of freedom that the learner needs to control.

Slide 118

And here is where our equipment comes in. As we look at the human body we can think about the trunk and upper extremities and we can think about the lower extremities. Walking demands that core strength and postural control. It also demands lower extremity strength and maintaining the center of gravity over the base of support. So think about the core stability and how the hand held support requires more independence on the part of the individual than support at the shoulders or trunk. In terms of the lower extremity we can provide weight bearing assist or we can provide guidance at the limbs.

Slide 119

Fading that physical support becomes very important and these examples are from the MOVE Curriculum in terms of transitioning from a solid mechanical support to where the child is able to simply walk with a flexible strap held between your hand and theirs.

Slides 120 – 121

So let’s now move to our product demonstration looking at prompt reduction concepts.