Does Mental Practice Enhance Performance?
Driskell, J. E., Copper, C., & Moran, A. · 1994
grade Cmeta-analysisindependentreplicated
Population
Mixed adult samples (students, athletes, trainees); tasks ranging from highly cognitive to purely physical
Design
Classic meta-analysis of mental practice (cognitive rehearsal without overt movement) vs no-practice controls. Aggregates small pre-1994 lab experiments, mostly immediate post-tests on researcher-designed or simple sport/cognitive tasks; no modern publication-bias correction. k not verified from the paywalled original.
Key findings
The canonical 'mental practice works' number: d≈0.53 vs no practice. Two deflators inside the paper itself: the effect is larger for cognitive than physical tasks, and it DECAYS with retention interval — much of it is temporary performance, not durable learning. The comparator is NO practice, not the real decision (imagery vs more physical practice).
Genetic confound
Not addressed; imagery ability varies widely between people and is a plausible unmodeled aptitude moderator.
Replication notes
Methodologically replicated by Toth et al. (2020) on 1995-2018 studies at roughly half the magnitude (r=.131 vs r=.255).
Effects
| Outcome | Metric | Value | Measure | Timing | Vs | Horizon | Class |
|---|---|---|---|---|---|---|---|
| Mental practice vs no practice, overall | Cohen d (r = .255) | d = 0.527, z = 9.73, p < .001 | mixed | mostly acquisition/immediate post-test; lab | business-as-usual | end-of-treatment | domain-skill |
| Task-type moderator | d by cognitive vs motor content | Larger the more cognitive the task; smaller for purely physical tasks | mixed | acquisition/immediate; lab | business-as-usual | end-of-treatment | domain-skill |
| Retention-interval moderator | d by delay between MP and performance | Effect DECAYS as the interval lengthens — largely a temporary benefit | mixed | retention; delayed; lab | business-as-usual | unclear | domain-skill |
| Practice-duration moderator | d by length of MP intervention | Moderated by length — more mental practice is not monotonically better | mixed | acquisition; lab | business-as-usual | end-of-treatment | domain-skill |
Cited by
- Feedback frequency and mental practice in motor learningmixedconf: highgc: low