前臂之间的测试触觉掩蔽
Summary
Here we explore contralateral tactile masking between the forearms in which tactile detection thresholds are modulated by vibration applied to a remote site. The details of which remote sites have an effect can tell us about how the body is represented in the brain.
Abstract
Masking, in which one stimulus affects the detection of another, is a classic technique that has been used in visual, auditory, and tactile research, usually using stimuli that are close together to reveal local interactions. Masking effects have also been demonstrated in which a tactile stimulus alters the perception of a touch at a distant location. Such effects can provide insight into how components of the body’s representations in the brain may be linked. Occasional reports have indicated that touches on one hand or forearm can affect tactile sensitivity at corresponding contralateral locations. To explore the matching of corresponding points across the body, we can measure the spatial tuning and effect of posture on contralateral masking. Careful controls are required to rule out direct effects of the remote stimulus, for example by mechanical transmission, and also attention effects in which thresholds may be altered by the participant’s attention being drawn away from the stimulus of interest. The use of this technique is beneficial as a behavioural measure for exploring which parts of the body are functionally connected and whether the two sides of the body interact in a somatotopic representation. This manuscript describes a behavioural protocol that can be used for studying contralateral tactile masking.
Introduction
触觉掩蔽是，其中在身体上的一个位置的触觉刺激改变在另一位置的触摸的感觉。这是由冯Bekesy 1率先露出位置的相互作用，特别是侧抑制，这是身体表面上的相邻的皮肤区域之间的技术。而触觉掩蔽已多年来广泛的研究，研究已经使用电刺激2，3，压力4和振动触觉刺激5,6主要研究同侧触觉掩蔽。相比之下，很少有研究着眼于对侧触觉掩蔽其中屏蔽和探测站点可能相去甚远。远距离触觉掩蔽效应已经示出镜面对称点之间的手和臂5,7 – 9但这些研究已经在很大程度上限于看手和手指的710，用全身的更广泛的地区基本上被忽视。这种远距离掩蔽实验的目的是为了表明如何人体的大脑中的代表性的成分可以功能性连接。这里，远程触觉掩蔽的现象是由调查如何施加到一个前臂振动可能会影响在相对前臂触觉敏感性阈值探讨。阈指的是需要检测的刺激的最小刺激。我们定义这个作为在该刺激被检测的75％的时间的强度。我们使用其中在一个前臂触觉敏感性（阈值的倒数）对身体的其他部分的振动刺激（掩模）的存在下测定的触觉掩模技术。有效掩蔽由增加了检测阈值，即 ，在灵敏度的降低表明。该技术可以与其它操作一起使用，如不同的肢体位置O- [R运动，探索其对屏蔽的效果影响。
在这里，我们使用振动触觉刺激作为掩蔽刺激。这样做的好处是，它刺激的频率，并且因此该受体类型可被控制。该技术可以扩展到看看使用电刺激作为探针或掩模或二者的疼痛。此外，任何部位可以用作掩蔽站点允许针刺部位例如调查。
Protocol
Representative Results
Discussion
这里，对于对侧触觉掩蔽一个详细的协议描述，并使用该技术来测试触觉检测阈值以前发表的结果示。这种方法的优点是，阈值被使用psychophysically严格技术测量。两替代强迫选择（2AFC）过程是相对不敏感的反应偏差，因此，从注意力的影响。因为大多数数据都与靠近阈值水平刺激强度收集关于实际阈值珩磨在自适应楼梯过程是非常有效的。蒙住眼睛的参与者，并让他们直视前方吞吐量数据采集?…
Disclosures
The authors have nothing to disclose.
Acknowledgements
LRH由加拿大自然科学和工程研究理事会（NSERC）的支持。 SD被部分从NSERC支持创建程序。
Materials
| C-2 tactor | ATAC Technology; Engineering Acoustics, Inc. | http://www.atactech.com/PR_tactors.html | |
| Magic Wand | Hitachi | http://magicwandoriginal.com/magic-wand-original/ | |
| FC5 Foot Pedals | Yamaha Corporation | http://ca.yamaha.com/en/products/music-production/accessories/footpedals/fc5/?mode=model | |
| MATLAB | The Mathworks, Inc. | http://www.mathworks.com/products/matlab/ | |
| Velcro | Velcro Industries B.V. | http://www.velcro.com/ |
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