Opsommer E, Weiss T, Miltner W H, Plaghki L
Faculty of Medicine, Université catholique de Louvain, Avenue Mounier 53/READ 5375, B-1200, Brussels, Belgium.
Clin Neurophysiol. 2001 Oct;112(10):1868-74. doi: 10.1016/s1388-2457(01)00622-8.
To investigate (1) the scalp topography of ultralate laser evoked potentials (LEPs) related to C-fibre activation, which can directly be obtained by thulium YAG (Tm YAG) laser stimulation of tiny skin surface areas (about 0.23 mm(2)) and (2) the influence of the performance of a motor task on ultralate LEPs.
Laser stimuli were applied to the dorsum of the left hand. LEPs were recorded with 58 scalp electrodes from 9 healthy subjects in two different conditions, with and without a reaction time (RT) task (press a button upon detection).
On high resolution electroenchephalogram recordings, ultralate LEPs were characterized by a broad positive component (peak latency: 1133+/-91 ms) with maximum amplitude about the vertex. Moreover, the performance of a RT task had no influence on latency, amplitude and topographical patterns of two maps chosen at the positive peak latency in ultralate LEPs. Nevertheless, a negative inflexion (latency 1300 ms) appeared after the positive component in the task condition possibly reflecting movement-related potentials.
Tm YAG laser stimulation of tiny skin surface areas allows recording the dynamic scalp topography of ultralate (C-fibres) LEPs, with or without the performance of a RT task.
研究（1）与C纤维激活相关的超晚期激光诱发电位（LEP）的头皮地形图，其可通过铥钇铝石榴石（Tm YAG）激光刺激微小皮肤表面积（约0.23平方毫米）直接获得，以及（2）运动任务表现对超晚期LEP的影响。
将激光刺激施加于左手背。在两种不同条件下，即有和没有反应时间（RT）任务（检测到后按按钮）时，用58个头皮电极记录9名健康受试者的LEP。
在高分辨率脑电图记录中，超晚期LEP的特征是一个广泛的正成分（峰值潜伏期：1133±91毫秒），在头顶处振幅最大。此外，RT任务的表现对超晚期LEP在正峰值潜伏期选择的两张图谱的潜伏期、振幅和地形图模式没有影响。然而，在任务条件下，正成分之后出现了一个负拐点（潜伏期1300毫秒），可能反映了与运动相关的电位。
Tm YAG激光刺激微小皮肤表面积能够记录超晚期（C纤维）LEP的动态头皮地形图，无论是否执行RT任务。
