Performance descriptive statistics, M(SD).

Non-dominant hand contractions (NDHCs) have been shown to help expert motor skills in high-pressure scenarios that induce performance anxiety. Most studies of NHDCs under pressure have examined benefits in overlearned specialist movements (e.g., sporting skills), while few have considered if NDHCs can aid common movements with population-wide expertise (e.g., typing). Accordingly, across three experiments, we explored if NDHCs could protect or facilitate performance under time and/or evaluation pressure in a cursor positioning task (Experiments 1 & 2) and a typing task (Experiment 3). Despite varying the nature of the task, pressure manipulation, and design, and successfully manipulating state anxiety in each experiment, we found no evidence that NDHCs assist performance under pressure in these tasks. For the pressure × contraction condition interaction, the largest inclusion Bayes Factor was .40 for task response time and .62 for task error (Experiment 1), indicating evidence in favour of a null result. Our results, along with other recent studies in this area, cast doubt on the benefits of NDHCs under pressure outside sporting tasks and underline the need for a better mechanistic account of the phenomenon.非利手收缩（Non-dominant hand contractions, NDHCs）已被证实可在引发表现焦虑的高压情境中，助力专家级运动技能的发挥。既往针对高压情境下非利手收缩的研究，多聚焦于过度学习的专业动作（如运动技能）中的收益，却极少探讨其能否帮助具备全民普及性熟练度的日常动作（如打字）。据此，本研究通过三项实验，探究了非利手收缩在计时和/或评估压力下，对光标定位任务（实验1与实验2）及打字任务（实验3）的表现是否具有保护或促进作用。尽管本研究对任务性质、压力操控方式与实验设计进行了变量控制，并在每项实验中成功引发了状态焦虑，但未发现任何证据表明非利手收缩能在上述任务的高压情境中改善表现。针对压力×收缩条件的交互效应，实验1中任务反应时的最大包含贝叶斯因子（Bayes Factor）为0.40，任务错误率的最大包含贝叶斯因子为0.62，这一结果支持了无效应的原假设。本研究结果与该领域近期其他研究一同，对非利手收缩在运动任务之外的高压情境中的收益提出了质疑，并强调了对该现象背后机制进行更完善阐释的必要性。