Meta-analyzing enhanced expectancies on motor learning: positive effects but methodological concerns

ABSTRACT

The OPTIMAL theory of motor learning predicts enhanced expectancies facilitate learning. This meta-analysis investigated this prediction by quantifying effect sizes from studies manipulating feedback after good trials, comparative feedback, perceived task difficulty, conceptions of ability, self-modeling, or extrinsic rewards, and assessing learning. After searching databases, 48 studies met inclusion criteria for quantitative analysis. Fifty-six effect sizes were calculated from performance differences between enhanced expectancies and neutral/diminished expectancies groups at delayed retention tests. Results revealed a Hedges’ g = 0.54 (95% CI [0.38, 0.69]) that may be overestimated due to small-study effects and underpowered studies. Moderator analyses revealed feedback after good trials, comparative feedback, perceived task difficulty, and conceptions of ability manipulations significantly improved learning. Few studies used other manipulations, precluding reliable estimates of their effects. Further, significant effects of enhanced expectancies were shown for children/adolescents, young adults, and older adults. Few studies examined special populations, preventing a reliable effect estimate. Finally, the effect of enhanced expectancies on learning was not affected by type of comparison group (neutral/diminished expectancies). Findings suggest enhanced expectancies may facilitate motor learning, consistent with OPTIMAL theory, but pre-registered/registered reports and more powerful studies should be conducted to confirm the effect and estimate its size more accurately.

KEYWORDS:

• OPTIMAL theory
• meta-analysis
• motivation
• self-efficacy
• motor skill

Data availability statement

The data that support the findings of this study and supplementary materials are openly available in the Open Science Framework (OSF) repository at https://osf.io/mbux2/?view_only=2dc9697af80342ebbaf4c86f562b8bdd.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Notes

1 Two reasons guided our decision to focus on performance on delayed retention test. First, there is no theoretical explanation as to why enhanced expectancies may affect retention and transfer test performance differently. Second, given the significant variability in types of transfers tests found in this literature, adding performance on delayed transfer test to our meta-analysis would likely introduce unnecessary heterogeneity to our data.

2 If summed, the number of manipulations exceeds the total number of effect sizes included in the meta-analysis. This is because one effect size reflects two manipulations combined (i.e., feedback after good trials and conceptions of ability; Wulf et al., 2013).

3 The study by Wulf et al. (2013) manipulated both conceptions of ability and feedback after good trials. Until this point, the effect size of this study reflected a combination of these two manipulations (acquirable-better group vs. inherent-worse group). However, for the purposes of this moderator analysis, we decided to categorize this study as ‘conceptions of ability’ by comparing the acquirable-worse group and inherent worse-group given that this manipulation had fewer cases (n = 6) than the feedback after good trials one (n = 13). (We chose to compare the acquirable- vs. inherent-worse groups because we reasoned the acquirable- and inherent-better groups may both have enhanced expectancies, with the latter believing they are naturally good at the task.) In the supplementary material, we present the results of a sensitivity analysis in which this study is classified as feedback after good trials (effect size reflecting the difference between the inherent-better and inherent-worse group).