Summers Ian R, Chanter Craig M
School of Physics, University of Exeter, United Kingdom.
J Acoust Soc Am. 2002 Nov;112(5 Pt 1):2118-26. doi: 10.1121/1.1510140.
A stimulator array is described which can deliver a wide range of displacement waveforms from each contactor, allowing vibratory stimuli to be targeted towards different populations of mechanoreceptors in the skin. The array has a working bandwidth of 20-400 Hz and 100 moving contactors covering an area of 1 cm2 on the fingertip. The array was validated with two experiments on the perception of moving vibratory targets within a uniform background vibration. In the first experiment, with target and background at the same frequency, equivalent discrimination of target movement was obtained at higher values of target/background amplitude ratio for 40-Hz stimuli than for 320-Hz stimuli. In the second experiment, discrimination of target movement within a different-frequency background (320-Hz target and 40-Hz background, or vice versa) was found to be much easier than within a same-frequency background. These results suggest that tactile spatial acuity is better at 320 Hz than 40 Hz and that it is possible to target different receptor populations in the skin by using these frequencies. However, there are problems with this interpretation: on the basis of characterization of touch receptors in previous studies, spatial acuity is expected to be worse at 320 Hz than at 40 Hz.
描述了一种刺激器阵列，其能够从每个接触器传递广泛的位移波形，从而使振动刺激能够针对皮肤中不同群体的机械感受器。该阵列的工作带宽为20 - 400Hz，有100个移动接触器，覆盖指尖上1平方厘米的区域。通过在均匀背景振动中对移动振动目标的感知进行的两个实验，对该阵列进行了验证。在第一个实验中，当目标和背景频率相同时，对于40Hz的刺激，在目标/背景振幅比更高的值时，获得了与320Hz刺激相当的目标运动辨别能力。在第二个实验中，发现在不同频率背景（320Hz目标和40Hz背景，或反之亦然）中辨别目标运动比在同频率背景中要容易得多。这些结果表明，320Hz时的触觉空间敏锐度比40Hz时更好，并且通过使用这些频率有可能针对皮肤中的不同受体群体。然而，这种解释存在问题：根据先前研究中对触觉感受器的表征，预计320Hz时的空间敏锐度比40Hz时更差。
