Motor Control Laboratory, School of Exercise and Nutritional Sciences, San Diego State University, San Diego, California 92182, USA.
Alcohol Clin Exp Res. 2012 Feb;36(2):302-9. doi: 10.1111/j.1530-0277.2011.01625.x. Epub 2011 Oct 20.
Production of isometric (i.e., constant) force is an essential component of performing everyday functional tasks, yet no studies have investigated how this type of force is regulated in children with confirmed histories of heavy prenatal alcohol exposure.
Children 7 to 17 years old with heavy prenatal alcohol exposure (n = 25) and without exposure (n = 18) applied force to a load cell to generate an isometric force that matched a criterion target force displayed on a computer monitor. Two levels of target force were investigated in combination with 3 levels of visual feedback frequency that appeared on the computer monitor as a series of yellow dots. Force was maintained for 20 seconds and participants completed 6 trials per test condition.
Root-mean-square error, signal-to-noise ratio, and sample entropy indexed response accuracy, response variability, and signal complexity, respectively. The analyses revealed that in comparison with controls, children with gestational ethanol exposure were significantly less accurate and more variable in regulating their force output and generated a response signal with greater regularity and less complexity in the time domain.
Children with prenatal alcohol exposure experience significant deficits in isometric force production that may impede their ability to perform basic motor skills and activities in everyday tasks.
产生等长（即恒定）力是执行日常功能任务的重要组成部分，但尚无研究调查在有明确的大量产前酒精暴露史的儿童中，这种类型的力是如何调节的。
7 至 17 岁的儿童有大量产前酒精暴露（n=25）和无暴露（n=18），他们向力传感器施加力，以产生与计算机监视器上显示的目标力相匹配的等长力。研究了两种目标力水平，并结合计算机监视器上显示的黄色点系列的三种视觉反馈频率水平进行了研究。力保持 20 秒，参与者在每个测试条件下完成 6 次试验。
均方根误差、信噪比和样本熵分别表示响应准确性、响应变异性和信号复杂性。分析表明，与对照组相比，胎儿乙醇暴露的儿童在调节其力量输出时准确性明显降低，变异性明显增加，并且在时域中产生的响应信号具有更大的规律性和更少的复杂性。
有产前酒精暴露的儿童在等长力产生方面存在明显缺陷，这可能会妨碍他们在日常任务中执行基本运动技能和活动的能力。
