Joint action syntax in Japanese martial arts

PLoS One. 2013 Sep 4;8(9):e72436. doi: 10.1371/journal.pone.0072436. eCollection 2013.

Abstract

Participation in interpersonal competitions, such as fencing or Japanese martial arts, requires players to make instantaneous decisions and execute appropriate motor behaviors in response to various situations. Such actions can be understood as complex phenomena emerging from simple principles. We examined the intentional switching dynamics associated with continuous movement during interpersonal competition in terms of their emergence from a simple syntax. Linear functions on return maps identified two attractors as well as the transitions between them. The effects of skill differences were evident in the second- and third-order state-transition diagrams for these two attractors. Our results suggest that abrupt switching between attractors is related to the diverse continuous movements resulting from quick responses to sudden changes in the environment. This abrupt-switching-quick-response behavior is characterized by a joint action syntax. The resulting hybrid dynamical system is composed of a higher module with discrete dynamics and a lower module with continuous dynamics. Our results suggest that intelligent human behavior and robust autonomy in real-life scenarios are based on this hybrid dynamical system, which connects interpersonal coordination and competition.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Competitive Behavior / physiology
  • Humans
  • Male
  • Martial Arts*
  • Movement / physiology*
  • Young Adult

Grants and funding

This work was partially supported by Grants-in-Aid for Scientific Research (A) 20240060 and 24240085 from MEXT, Japan and a Grant-in-Aid for Challenging Exploratory Research 22650146 from the JSPS, Japan. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.