Craig James C, Belser Adrienne N
Department of Psychology, Indiana University, Bloomington, IN 47405, USA.
Perception. 2006;35(11):1561-72. doi: 10.1068/p5481.
Several recent studies have shown that judgments of temporal order for tactile stimuli presented to the two hands are greatly affected by crossing the hands. The size of the threshold for judging temporal order may be up to four times larger with the hands crossed as compared to the hands uncrossed. The results from these recent studies suggest that with crossed hands, contrary to many situations involving the integration of tactile and proprioceptive information, subjects have difficulty in adjusting their perception of tactile inputs to correspond with the spatial positions of the hands. In the present study we examined the effect of training in judging temporal order on the size of this crossed-hands deficit--the difference in the thresholds for temporal-order judgments when the hands are crossed and uncrossed. All training procedures produced significant declines in the size of the deficit. With training, the difference between crossed-hands and uncrossed-hands temporal-order thresholds dropped from several hundred milliseconds to as little as 19 ms. A group of percussionists with experience in playing with crossed hands showed the same crossed-hands effects as non-musicians. The results were consistent in showing that the crossed-hands deficit was never completely eliminated but was greatly reduced with training. The implication is that subjects are able to adjust to the crossed-hands posture with modest amounts of training. The results are discussed in terms of the explanations that have been offered for the crossed-hands deficit.
最近的几项研究表明，呈现给双手的触觉刺激的时间顺序判断会受到双手交叉的极大影响。与双手不交叉相比，双手交叉时判断时间顺序的阈值大小可能会高出四倍。这些最新研究的结果表明，与许多涉及触觉和本体感觉信息整合的情况相反，双手交叉时，受试者难以调整他们对触觉输入的感知，以使其与双手的空间位置相对应。在本研究中，我们考察了时间顺序判断训练对这种双手交叉缺陷大小的影响——双手交叉和不交叉时时间顺序判断阈值的差异。所有训练程序都使缺陷大小显著下降。通过训练，双手交叉和不交叉时的时间顺序阈值之差从几百毫秒降至低至19毫秒。一组有双手交叉演奏经验的打击乐手表现出与非音乐家相同的双手交叉效应。结果一致表明，双手交叉缺陷从未完全消除，但通过训练可大大减少。这意味着受试者能够通过适量训练适应双手交叉的姿势。我们根据针对双手交叉缺陷所提出的解释对结果进行了讨论。
