Nefs Harold T, Kappers Astrid M L, Koenderink Jan J
Helmholtz Instituut, Department of Physics of Man, Universiteit Utrecht, Princetonplein 5, 3584 CC Utrecht, The Netherlands.
Exp Brain Res. 2005 May;163(1):123-7. doi: 10.1007/s00221-005-2227-8. Epub 2005 Mar 15.
For intermanual tactual discrimination to occur, it is thought that neural signals have to cross the corpus callosum in some way at least once. In this note we address the question of whether this interhemispheric transfer affects grating discrimination in active touch. Eight right-handed participants made intermanual and intramanual tactual discriminations of sinusoidal gratings that had slightly different spatial periods. Intramanual discrimination included comparisons in which the gratings were felt with the same finger, as well as comparisons made with two different fingers of the same hand. During intermanual discrimination the gratings were felt with corresponding fingers or with non-corresponding fingers of different hands. We found that thresholds for intramanual conditions were lower than for intermanual conditions in active dynamic touch. This suggests that there is a component of the task that is unilateral, as might be mediated by a somatosensory region that has predominantly or exclusively contralateral receptive fields.
为了实现双手间触觉辨别，人们认为神经信号必须至少以某种方式穿过胼胝体一次。在本报告中，我们探讨了这种半球间传递是否会影响主动触摸中光栅辨别的问题。八名右利手参与者对空间周期略有不同的正弦光栅进行了双手间和单手内的触觉辨别。单手内辨别包括用同一手指感受光栅的比较，以及用同一只手的两个不同手指进行的比较。在双手间辨别过程中，用不同手的对应手指或非对应手指感受光栅。我们发现，在主动动态触摸中，单手条件下的阈值低于双手条件下的阈值。这表明该任务存在一个单侧性的成分，可能由主要或专门具有对侧感受野的体感区域介导。
