Otto Selz Institute for Applied Psychology, Mannheim Centre for Work and Health, University of Mannheim, 68131, Mannheim, Germany.
Exp Brain Res. 2010 Sep;206(1):47-57. doi: 10.1007/s00221-010-2396-y. Epub 2010 Aug 17.
It is an unresolved question whether the posture of single fingers relative to each other is represented in the brain within an external frame of reference. In two experiments, we investigated postural influences on the processing of tactile stimuli at fingers and hands. Healthy subjects received two simultaneous tactile stimuli at the fingertips while the fingers of both hands were either interleaved or not. In speeded response tasks, they were asked to discriminate (experiment 1) or to identify (experiment 2) the touched body parts, either regarding hand laterality or finger type. The results demonstrate that both finger discrimination and finger identification are influenced by body posture. We conclude that the assumption of a solely somatotopic representation of fingers is not tenable and that an external reference system must be available for the detection of single fingers. The results are discussed in terms of a mental segmentation of external space, based on body posture and task requirements.
手指之间的相对姿势是否在大脑中以外部参照系来表示，这是一个尚未解决的问题。在两项实验中，我们研究了姿势对指尖触觉刺激处理的影响。健康受试者在双手手指交错或不交错的情况下，同时接受两个指尖的触觉刺激。在快速反应任务中，他们被要求辨别（实验 1）或识别（实验 2）被触摸的身体部位，无论是关于手的左右侧还是手指类型。结果表明，手指的辨别和识别都受到身体姿势的影响。我们的结论是，不能仅仅假设手指有一个单纯的躯体定位代表，必须有一个外部参照系来检测单个手指。根据基于身体姿势和任务要求的外部空间的心理分割，对结果进行了讨论。
