Self-confidence and performance: A little self-doubt helps.

Objectives: To test the hypothesis that a decrease in confidence on a well-learned task will increase effort and performance. Design: A 2 (group: control, experimental) 2 (trial: practice, competition) mixed-model with repeated measures on the second factor. Method: Expert skippers’ (n ¼ 28) self-confidence was reduced via a combination of task (i.e., change of rope) and competitive demands. Performance was the number of skips in a 1-min period. On-task effort was measured via the verbal reaction time to an auditory probe. Results: The group trial interaction (F (1, 26) ¼ 6.73, p < .05, h2 ¼ .21) supported the hypothesis: Posthoc tests revealed a significant decrease in self-confidence and a significant improvement in performance from practice to competition for the experimental group only. No significant effort effects were revealed. Conclusions: Some self-doubt can benefit performance, which calls into question the widely accepted positive linear relationship between self-confidence and performance. As effort did not increase with decreased confidence, the precise mechanisms via which self-confidence will lead to an increase or a decrease in performance remain to be elucidated.N/