Abstract
It has been reported that the latency of sympathetic skin response (SSR) on the fingertip is shorter than the latency on the palm. The purpose of this study is to compare the arising time (latency) of SSRs on the fingertips with that time on the palm. The SSRs evoked by the stimulation were simultaneously obtained from Ag-AgCl electrodes placed on the four fingertips and palm of hand in normal 8 male and 17 female subjects. A reference electrode was placed on ipsilateral thumbnail. We defined as a “fingertip fast” the group that the latency of SSR on the fingertip is shorter 0.1 sec than that on the palm, “same speed” the group that the difference between the fingertip and the palm is less than 0.1 sec and “fingertip delay” the group that the fingertip is longer 0.1sec than the palm. The fingertip fast group had 9 subject (41%) in the sound stimulation and 11 subject (44%) in the deep inspiration respectively, and also 7 subject (32%) and 8 subject (32%) respectively were the same speed group, 6 subject (27%) and 6 subject (24%) respectively belonged in the fingertip delay group. The significant difference of latency between the fingertip and the palm was recognized in both of the sound and deep inspiration stimulation. However, we did not have known why the latency of fingertip SSR was shorter than palm SSR. We will study in the future about this reason from the following points: sweating function of fingertip, the mechanism of the SSR generator. [Jpn J Physiol 55 Suppl:S191 (2005)]
