Athletes who squeezed a ball with their left hand immediately prior to execution of sports activities did not show performance deterioration under severe pressure (Beckmann, Gröpel, & Ehrlenspiel, 2013). This result has been explained by priming of the dominant right hemisphere. However, it remains unclear what variables have the greatest effect on asymmetrical brain activity (e.g., duration and strength of ball squeezing). We hypothesized that squeezing a ball harder for a longer period might lead to stronger asymmetrical activity because motor-related areas would have increased activation due to the more forceful movement. We used electroencephalograms (EEGs) to investigate the hemispheric asymmetry of brain activity produced by squeezing a ball with a unilateral hand. EEGs were assessed during a baseline period as well as in eight experimental conditions wherein the strength and duration of the ball squeeze were manipulated. Our results showed that right-hemispheric-dominant brain activation was maximized when participants squeezed with their left hand a ball that had an internal pressure of 100 hPa for 90 s or 20 hPa for 30 s. Moreover, squeezing the ball with 100 hPa internal pressure for 90 s created a prominent interhemispheric asymmetry of cortical activity. We suspect that squeezing a ball strongly for a long period might be helpful in dealing with “choking” under pressure by producing greater right-hemispheric activation. This result could help improve simple methods for competitive athletes to reduce the likelihood of exhibiting choking behavior that could be practiced with minimal effort, even during short breaks during a game.

中文翻译：

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单侧手部收缩对皮层活动的半球不对称持续性的影响

在进行体育活动之前立即用左手挤压球的运动员在剧烈的压力下并没有表现出运动成绩下降（Beckmann，Gröpel和Ehrlenspiel，2013年）。该结果已通过启动优势右半球来解释。但是，尚不清楚哪些变量对不对称大脑活动的影响最大（例如，持续时间和挤压球的强度）。我们假设长时间用力挤压球可能会导致更强的不对称运动，因为与运动相关的区域由于更加有力的运动而具有增强的激活性。我们使用脑电图（EEG）研究了用单侧手挤压球产生的大脑活动的半球不对称性。在基线期以及在八种实验条件下评估了脑电图，在这些条件下操纵了球挤压的强度和持续时间。我们的结果表明，当参与者用左手挤压内部压力为100 hPa持续90 s或20 hPa持续30 s的球时，右半球主导的大脑激活被最大化。此外，在100 hPa内压下将球挤压90 s会产生明显的半球间皮层活动不对称性。我们怀疑长时间强力挤压球可能会通过产生更大的右半球激活来应对压力下的“窒息”。这个结果可以帮助改进竞技运动员的简单方法，以减少表现出窒息行为的可能性，而这种行为可以通过最小的努力来实现，