3.1 OPTIMAL Theory of Motor Learning
In 2016, Gabriele Wulf and Rebecca Lewthwaite saw the lack in theoretical perspective on how specific practice methods could affect learning and performance. With the recent findings (relative to 2016) on the benefits of motivation and attention on learning, they proposed the OPTIMAL theory of motor learning. It was posited that motivational elements of enhanced expectancies and autonomy, with the attentional element of external focus, when working altogether, would reduce self-focus and increase task goal focus, and in turn enhance motor performance and learning. This is illustrated by Figure 1, which was published in the 2016 study.
Figure 1
(Wulf & Lewthwaite, 2016, p.1391)
Wulf and Lewthwaite (2016), when analysing the practical implications of the theory and schematic, suggested the idea of virtuous and vicious cycles. In a typical learning situation of a teacher and a student, when the knowledge is transferred through autonomous means, while enhancing student expectancies, and through a focus that is external, it will lead to a virtuous cycle in which motor learning and performance is continuously enhanced. This is illustrated by Figure 2.
Figure 2
(Wulf et al., p.1405)
However, the theory also postulated that the reverse is true; if the teacher threatens the learner’s autonomy, reduces their expectancies and teaches through internal focus, it leads to an overwhelming self-focus with low levels of focus on task goal and non-optimal motor learning and performance. This leads to a vicious cycle, as seen in Figure 3.
Figure 3
(Wulf et al., p.1405)
Wulf and Lewthwaite concluded with twelve predictions of the OPTIMAL theory, which either explained the relationships in the OPTIMAL theory schematic (Fig. 1), or would be explained through the subsequent sections of this chapter.
The subsequent subchapters serve as a summary of the explanation of the three elements of the theory: autonomy, enhanced expectancies, and external focus, as well as the idea on the “goal-action coupling” effect as termed by Wulf and Lewthwaite (2016). By doing so, they provide the grounds for the twelve predictions of the OPTIMAL theory.
As seen in Figure 2, the virtuous cycle illustrates that enhanced motor learning will lead to enhanced motor performance, in which it leads back to enhanced motor learning, effectively creating an endless loop. Hence, the terms “motor learning” and “motor performance” can be seen as interchangeable in the coming chapters and subchapters since they are essentially co-dependent.
Autonomy
Deci and Ryan’s self-determination theory (2000) identified three innate psychological needs: competence, autonomy and relatedness. When fulfilled, these psychological needs would enhance an individual’s motivation, as well as their mental health. It was also found through a number of studies that providing the individual the control over their practice would be beneficial to motor learning. Defined as the “[active] participat[tion] in determining one’s own behaviour”, autonomy benefits motor learning through deeper processing of relevant information, encouragement of error estimation, increased usage of self-regulation strategies, motivation, and increased task interest (Wulf et al., 2016).
Instead of viewing autonomy as a direct influence on motor learning, Wulf et al. (2016) argued that autonomy has a closer correlation to motivation, which then manifests in the motor learning and performance of individuals. They posited that “[c]onditions that provide an opportunity for choice may be motivating, because they indicate that one will be able to control upcoming events.” The two researchers also noted that even when having a minute effect on the result, the perception of control can increase motivation.
One method of increasing autonomy is through the control of learning conditions. This was studied extensively through numerous research through a yoking procedure. This allowed for comparisons between participants in a yoked group, that received feedback on an externally fixed schedule, and a self-control group, in which participants chose when they wanted to receive feedback. Wulf et al. (2016) drew evidence from throwing tasks, virtual tasks, observational learning, and even in a graffiti language learning task, showing that enhanced learning was presented in the group that received self-controlled feedback. Interestingly, Wulf and Lewthwaite also highlighted the virtue of choice in assistive devices, even when the devices had no extra help enhanced learning. This was seen through both healthy participants as well as in individuals with Parkinson’s Disease.
More effective learning (as compared to the yoked group) was also seen when participants, no matter their skill level, were allowed to make decisions relevant to the motor task such as the amount of extent and space between practice or choosing the order of exercises. However, when task-irrelevant choices (known as “incidental choices”) (e.g., choosing the colour of golf balls to putt, colour of balls to throw, or choosing a painting to be hung in the laboratory when doing a balancing task) were presented to individuals, they too, showed enhanced learning (Wulf et al. 2016).
Wulf et al. (2016) also highlighted that another key to unlocking autonomy was the usage of instructional language. Instructions that enable autonomy leads to superior learning over instructions that restricts the learner’s ability to exercise personal control. Cortisol responses were also noted to be different between controlling and autonomy inducing instructions. The OPTIMAL theory predicts that “Autonomy support facilitates performance by enhancing expectancies”. Furthermore, Girelli et al. (2018) supports the prediction with their findings that students who had enhanced autonomy from parents and teachers were found to have improved self-efficacy in their studies. We will delve into self-efficacy in the next section, “Enhanced Expectancies”.
Enhanced Expectancies
In the OPTIMAL theory, enhanced expectancies was defined as “a range of forward-directed anticipatory or predictive cognitions or beliefs about what is to occur” (Wulf et al., 2016). It goes on to mention that theyencompass self-efficacy and outcome expectations, including placebos, as well as signals predicting extrinsic rewards. However, Wulf et al. (2016) stated that the type of expectation that is extremely relevant to motor learning and performance would be self-efficacy expectations. This is also further corroborated in a meta-analysis by Moritz, Feltz, Fahrbach & Mack (2000) which found a significant correlation between self-efficacy and performance in sports through analysing 45 studies (or 102 correlations) that were previously done.
Self-efficacy, a concept first introduced by psychologist Albert Bandura in 1977, refers to the self-belief of an individual in their ability to attain specific task outcomes. The theory also proposed that the successes or failures from past experiences are the main determinants of an individual’s self-efficacy level. Self-efficacy will be explained in greater details in Chapter 3.2.
Wulf et al. (2016), through substantiating with numerous research done, further discussed the factors that enhanced motor learning and performance through enhancing efficacy levels during practice. These were:
a) Positive feedback
More effective learning can be achieved through highlighting successful performances while looking past less successful ones. For example, a music teacher saying “That sounded great!” or “I am impressed by your improvement!” to their student, instead of “You played this wrong.”
b) Social-comparative feedback
Social-comparative feedback determined efficacy levels through the evaluation of one’s competence through normative information (information about the average performance of peers). Studies showed that individuals receiving positive normative feedback fared better in learning than their peers receiving negative or even no normative feedback at all. The last two groups also demonstrated lower levels of motor control in terms of automaticity and efficiency. In a scenario of music competitions, if an individual were to hear their competitors playing much worse than themself, this individual would most likely be more confident in their abilities on stage. Likewise, the reverse is true.
Besides better motor performance and learning, positive normative feedback was identified to “increase perceived competence, reduce concerns and nervousness about performance and ability, increase satisfaction with performance and motivation to learn, and increase positive affect” (Wulf et al., 2016). On the flipside, negative normative feedback was shown to “trigger thoughts about the self and resulting self-regulatory activities that hamper learning of the primary task”, as well as inducing “defensive, self-enhancing reactions to the self-related threat” (Wulf et al., 2016).
c) Self-modeling
Another suggestion by Wulf and Lewthwaite (2016), was to enhance efficacy levels through “self-modeling”, a term that was coined through studies that investigated learning through the feedback from an edited video feedback of the participants’ best performance. This method proved to enhance learning, motivation and satisfaction with performance.
d) Perceived task difficulty
Perceived task difficulty was another factor that could influence an individual’s efficacy. Musicians that receive appraisal of their abilities, set relatively attainable goals, define their successes more liberally, have faith or perception that certain objects will boost performance, undergo hypnosis, or have positive beliefs of performing well under certain conditions (e.g. pressure) would more likely to view performance less difficult. Therefore, they would have more of a self-efficacious perception of performing.
e) Conceptions of ability
The individual’s conception of their own abilities - as either fixed at a certain standard or malleable with time and effort - was established to affect efficacy levels as well in the theory. Musicians that view their ability as fixed (also known as entity theorists) are relatively more focused on proving themselves, and are easily intimidated by mistakes or negative feedback since they expose shortfalls. Conversely, musicians that view their ability and alterable (also known as incremental theorists) are less intimidated by mistakes or negative feedback, and view them as temporal and inherent in the learning process. These musicians are at a higher disposition to tackle challenges through practice, and are relatively more concerned with growth and improvement on any given task.
By studying entity theorists or inducing an entity mindset in children, it was found that they showed less motivation, greater negative self-assessment, regression of motor performance, and relatively ineffective learning. In adults, innate incremental theorists or an induced incremental mindset showed higher self-efficacy levels, greater positive affective self-reactions, more task interest, enhanced learning, as well as greater motor performance and automaticity (Wulf et al., 2016).
f) Extrinsic rewards
Extrinsic rewards was considered a factor in enhancing expectancies as it presents the effects of expectations through “anticipation of reward (broadly defined) or reward prediction error” (Wulf et al., 2016). Monetary prospects were shown to improve motor performance in individuals afflicted with Parkinson’s disease, as well as in healthy individuals. (Wulf et al., 2016)
g) Positive affect
Positive affect refers to the inclination of an individual to experience positive moods. As goals are achieved, positive affect can be expected. Musicians that are inclined to be positive, would anticipate positive affects before learning or performing, turning the positive affect into a sense of reward, and in turn leading to enhanced expectancies. Positive affect has been shown to improve cognition in healthy individuals, as well as in individuals with Parkinson’s disease (Wulf et al., 2016).
Enhanced expectancies, with the goal-action coupling, was suggested by Wulf et al. (2016) to have a dual role of increasing task goal focus as well as reducing self-focus, which is illustrated in the model for the OPTIMAL theory. The reverse was also hypothesised to be true, in which levels of expectancies on the other side of the spectrum would “activate conflicting responses or act in the manner of a self-invoking trigger, inviting potentially task-incompatible concerns, anxiety, negative affective reactions, and neuromuscular activity, necessitating resource deployment to self-regulation and recovery” (Wulf et al., 2016).
Wulf et al., (2016) revealed that studies showed that sporadic application of challenge or stress, although temporarily reducing dopamine levels from anticipated reward, demonstrated enhanced learning when it resulted in a positive performance. Due to greater effort and attention, which ultimately improves performance, the potential of achieving success under challenge brings about greater learning and retention.
External Focus
An external focus of attention refers to the act of concentration on the intended movement effect, while an internal focus of attention refers to the act of concentration on the movement instead. The link between external focus and enhanced motor learning was first published in 1998 by Wulf, Höß and Prinz, in which they were studying the effects of how instructions that induced different focus of attention would enhance motor skill learning through two experiments.
The first experiment involved two groups of participants using a ski-simulator, one group focusing on exerting force on their feet (internal focus), while the other focusing on exerting force on the wheels of the machine (external focus). The second experiment was carried out to “examine the robustness and generalizability of the findings of Experiment 1” (Wulf, Höß, & Prinz, 1998) and saw participants performing a stabilometer task. The internal focus group were asked to focus on their feet and keep them at the same height while the external focus group were asked to focus on the markers attached to the machine’s platform. In the retention tests (a test of the same task given after practice trials) of both experiments, the external focus group consistently showed enhanced learning than their counterparts.
Following the 1998 study, numerous studies followed up with investigations on various motor movements and the benefits external focus brought about. Wulf et al., (2016) looked into these studies, organised them based on the benefits they had, and these were:
a) Movement effectiveness (balance and accuracy)
b) Movement efficiency (muscular activity, maximum force production, speed, and endurance)
c) Movement form
d) Promotion of automaticity
Besides showing these results in retention tests, they were also seen in transfer tests, which are tests of a different but related task from the practised task. These studies were all done through experiments from a variety of sports (e.g. golf, darts, basketball, swimming, rowing, frisbee, etc.), as well as gross motor skills (e.g. jumping, balancing, running, weight lifting, etc.) and all showed that external focus consistently presented better results in terms of the benefits mentioned above, as compared to internal focus. Wulf et al. (2016) noted that the same effect was also seen through varying skill, age, as well as other differences in individuals.
The first time the focal length of external focus was investigated was in a 2003 study carried out by McNevin, Shea and Wulf. It was observed that when the markers of the balance platform were placed at a greater distance from the feet, participants fared better in a balance task on a stabilometer. This showed that the further the focus was away from the body, the greater the enhancement of motor learning and performance. Since then, numerous studies have substantiated this through a range of movement types and sports such as golfing (Kearney, 2015), dart throwing (McKay & Wulf, 2012), standing long jump (King & Power, 2021), kayak sprinting (Banks, Higgins, Sproule, & Wulf, 2015).
Through all the studies examined in the theory, both internal and external foci were prescribed through the use of instructions, demonstrating its innate powers (when accurately given) in enhancing learning and performance. Wulf et al., (2016), through referencing the studies by Richard Masters, where implicit learning showed enhanced motor learning and performance, suggested that instructions should be “kept to a minimum” since “they increase the likelihood that learners “reinvest” acquired knowledge and engage in conscious control processes that interfere with the automatic execution of the movement”.
Wulf et al., (2016) attributed the effectiveness of external focus to the constrained action hypothesis (Wulf, McNevin, & Shea, 2001). It was hypothesised that when consciously trying to control movement that is automatic, it interferes with the natural processes that regulate it. On the other hand, when focusing on the effect that the movement has, it provides freedom for the body in producing these movements and by doing so, enhances motor learning and performance.
Wulf et al., (2016) also proposed that the effects brought about by external focus were brought about by the dual role of promoting task goal focus while reducing self focus. Through this virtue, motor performance is more successful, which results in enhanced expectancies. This cyclical relationship is illustrated by the arrow linking improved motor performance back to enhanced expectancies in Figure 1. Hence, it can be seen that the three elements of autonomy, enhanced expectancies and external focus do have influence on each other, which is explained by the “goal-action coupling” effect as described in Figure 1. This will be further discussed in the next subchapter.
An example by Wulf and Lewthwaithe (2016) aptly sums up the fundamental need for external focus, in which they highlighted the intrinsic nature of it through a evolutionary standpoint:
“What does the mountain goat about to jump across a chasm focus on? Presumably, it focuses on the other side of the chasm to which it is jumping. Its motor system seems to “know” what it has to do to achieve the desired outcome. …It is hard to imagine other animals moving affirmatively for food or survival with a constant internal conversation regarding how to move their limbs most effectively. Likely, they pursue their goals with purpose and action unimpaired by digressions into self-reflection or concerns about how to coordinate their muscles and joints.”
Goal-action Coupling
Studies have demonstrated the cumulative effect when autonomy, enhanced expectancies and external focus were involved in the learning process. This was first investigated through the series of studies by Wulf (in groups of two elements, and the three permutations) of the additive benefits of:
a) Autonomy support and enhanced expectancies (Wulf, Chiviacowsky, & Cardozo, 2014)
b) External focus and autonomy support (Wulf, Chiviacowsky, & Drews, 2015)
c) External focus and enhanced expectancies (Pascua, Wulf, & Lewthwaite, 2015)
All three studies involved participants learning and performing a throwing task with their non-dominant hand. Participants were split into four groups, the first group were to receive two elements (out of the three of autonomy, enhanced expectancies and external focus), a second group to receive one element, the third group to receive the other element and final group which was the control group that did not receive any of the elements. All three studies conclusively demonstrated through their respective retention and transfer tests that the group exposed to the combination of two elements consistently outperformed the other three groups.
Abdollahipour, Nieto, Psotta and Wulf (2017) also replicated the same results when investigating the additive benefits of external focus and autonomy support on children performing a bowling task.
And finally in 2018, the trifecta of the OPTIMAL theory elements were put to the test for additive benefits in a study by Wulf, Lewthwaite, Cardozo and Chiviacowsky. Participants were placed into groups of four, with the first three groups assigned a permutation of two of the three elements, and the final group having exposure to all three elements. Similar to the series of studies earlier, participants were once again asked to perform a throwing task with their non-dominant hand. The retention test not only proved that the group with the combination of all three elements had the highest accuracy scores but also proved that it was the only group that showed an improvement in accuracy as compared to the pre-test scores. It was also noted that the other three groups produced similar results, no matter the permutation of elements.
The idea of goal-action coupling of the motivation (enhanced expectancies and autonomy) and external focus was explained through a neuroscientific approach. Wulf et al. (2016) hypothesised that with optimal motivation and external focus, enhanced neural connections lead to better learning and performance. This was attributed to the strengthened connections in the grey and white matter in the brain when practising or performing.
As mentioned previously, with the goal-action coupling, the three elements of the theory lead to enhanced motor performance. Successful motor performances will greatly enhance expectancies and release higher levels of dopamine, the chemical in the brain associated with anticipation of reward. Dopamine is shown to create stronger and long-term cellular connections, enhance new neutral connections, is involved with the memory of motor skills before and after practice, and contributes to consolidation by enhancing the reactivation of memories during rest. (Wulf et al., 2016)
[Next: Chapter 3.2 - Literature Directly Related to the OPTIMAL Theory]