Abstract
A cutaneous electrical stimulation (CES) was applied to the skin over the left and right anterior tibial muscles of eight normal subjects, and the effect on reaction times (RTs) of finger extensions on the left and light hands was studied. RTs of fingers of both hands decreased significantly after receiving CES on the left while RTs of fingers of the right hand only decrease after receiving CES on the right. These results suggest that the left and right CESs differ from each other in the effect on behavioral alertness. If it is assumed that the pain relieving effect of CES is generated via the central arousal mechanism, this finding is critical in clinical application of the CES for relieving pain.
