To clarify whether there is left-right difference in arousal induced by position changes, vocal reaction times (RTs) were measured at three different positions of the arms for 10 normal subjects. RTs at the facilitating position of either arm were faster than RTs at the neutral position, and RTs at the facilitating position of the left arm were faster than those of the right. The results indicate that the left facilitating position is more effective for increasing arousal than the right one.