Nishimura, A. 1, 2 , Ariga, A. 3 & Michimata, C. 1
1 Department of Psychology. Sophia University. Tokyo, Japan.
2 JSPS. Tokyo, Japan.
3 Department of Psychology. Rissho University. Tokyo, Japan.
We investigated the effects of direction (left, right), identity (left hand, right hand), and finger (index finger, little finger) of a task-irrelevant pointing hand stimulus on bimanual left/right key press responses with index or little fingers. Participants made left or right key press response according to the color of a centrally presented target. Before the onset of the target, a pointing hand stimulus, which was irrelevant to the task, was briefly presented at the center of the screen. The spatial correspondence effect based on the pointing direction and the response key position was larger for the hand stimulus of index finger pointing than of little finger pointing, indicating the spatial compatibility effect based on others’ intention. The stimulus-response hand correspondence exerted a positive effect when the responses were made with little fingers, but the effect was negative when the responses were made with index fingers. The results indicate the importance of controllability of the effector in automatic imitation. The present study showed multiple automatic influences induced by perception of others’ pointing hand on our own action.