Preemptive Action: Accelerating Human Reaction using Electrical Muscle Stimulation

Shunichi Kasahara / (SonyCSL)
Jun Nishida (The University of Chicago)
Pedro Lopes  (The University of Chicago)
本プロジェクトは、シカゴ大学の西田 惇氏、Pedro Lopes氏との共同研究です。

Even computer actuates us before our will, we perceive  “I did it” in some condition. We investigate time window and foundation of the induction of pseudo Sense of Agency with the preemptive action with EMS (Electrical muscle stimulation).

Limen for generating the sense of agency with the computational preemption

As the evolution of computer prediction and technology for direct control of the body itself, it will be possible to drive our body faster and more accurately than our own will. With this situation, what we have to guarantee is the sense of agency : the subjective awareness of initiating, executing, and controlling one’s own volitional actions.

In this project, by using the EMS (muscle electrical stimulation), we artificially archived faster and voluntary congruent finger motion and then measured perceived agency score with various preemption parameters. We found that, when the user and system move congruently, user feels that they initiated the motion, yet their reaction time is faster than usual. Our analysis uncovered that there is a time window to hold the sense of agency even if it precedes the usual visual reaction by approximately 80-100 msec faster.

This is a collaborative research project with Jun Nishida and Pedro Lopes  (The University of Chicago).

Talk / Presentation

Shunichi Kasahara, Jun Nishida, and Pedro Lopes. 2019. Preemptive Action: Accelerating Human Reaction using Electrical Muscle Stimulation Without Compromising Agency, In CHI Conference on Human Factors in Computing Systems Proceedings (CHI 2019), May 4–9, 2019, Glasgow, Scotland Uk. ACM, New York, NY, USA, 15 pages.

Jun Nishida, Shunichi Kasahara, and Pedro Lopes. 2019. Demonstrating preemptive reaction: accelerating human reaction using electrical muscle stimulation without compromising agency. In ACM SIGGRAPH 2019 Emerging Technologies (SIGGRAPH ’19). ACM, New York, NY, USA, Article 10, 2 pages. DOI:
(Laval Virtual Grand Prize)


— Japanese —

Preemptive Action  : 意志よりも早く動かされる身体”自分がやった”知覚の境界を探る

自分の意志によって身体が動く前に、コンピュータによって“動かされた”としても、その行為を”自らが行った” (Sense of Agency)と知覚することがある。本研究は、EMS(筋電気刺激) を用いて、その時間的領域と成立条件を探る。


コンピュータによる予測性能の向上と、身体そのものを直接制御するテクノロジの進化によって、自分の意志よりも早く・正確に自身の身体を駆動させることが可能になる。その時保障するべきは、行為の主体は自分であるという感覚(Sense of Agency)であり、これを生み出すための制御基盤が今後重要になる。

本研究では、 EMS(筋電気刺激) を用いて、人工的に自分の意志と同じであるが、自分の能力よりも早く身体(指)を駆動させ、その行為に対する行為主体感計測した。結果、通常の視覚反応よりも約80-100msec 時間先行させても行為主体感を保持する時間境界があることが示唆された。

Related Work:

Jun Nishida, Shunichi Kasahara, and Kenji Suzuki. 2017. Wired muscle: generating faster kinesthetic reaction by inter-personally connecting muscles. In ACM SIGGRAPH 2017 Emerging Technologies (SIGGRAPH ’17). ACM, New York, NY, USA, Article 26, 2 pages. DOI:

Posted by:shunichikasahara