Department of Neuroscience, Johns Hopkins University School of Medicine, 813 Wood Basic Science Building, 725 N. Wolfe Street, Baltimore, MD 21205, USA.
Neuron. 2011 Feb 10;69(3):536-47. doi: 10.1016/j.neuron.2010.12.033.
How are local motion signals integrated to form a global motion percept? We investigate the neural mechanisms of tactile motion integration by presenting tactile gratings and plaids to the fingertips of monkeys, using the tactile analogue of a visual monitor and recording the responses evoked in somatosensory cortical neurons. The perceived directions of the gratings and plaids are measured in parallel psychophysical experiments. We identify a population of somatosensory neurons that exhibit integration properties comparable to those induced by analogous visual stimuli in area MT and find that these neural responses account for the perceived direction of the stimuli across all stimulus conditions tested. The preferred direction of the neurons and the perceived direction of the stimuli can be predicted from the weighted average of the directions of the individual stimulus features, highlighting that the somatosensory system implements a vector average mechanism to compute tactile motion direction that bears striking similarities to its visual counterpart.
局部运动信号如何整合形成整体运动知觉？我们通过向猴子指尖呈现触觉光栅和条带，利用视觉显示器的触觉模拟，并记录在躯体感觉皮层神经元中引发的反应，研究了触觉运动整合的神经机制。在平行的心理物理学实验中测量光栅和条带的感知方向。我们鉴定出一群体感神经元，其整合特性可与 MT 区中类似的视觉刺激诱导的特性相媲美，并发现这些神经反应可以解释在所有测试刺激条件下感知到的刺激方向。神经元的最佳方向和刺激的感知方向可以从各个刺激特征方向的加权平均值中预测出来，这突出表明，躯体感觉系统实现了一种矢量平均机制来计算触觉运动方向，这与视觉系统非常相似。
