We studied coordination and movement kinematics in a mirror game. 32 participants (18 f, 14 m; mean age 25.2 years, range 19–37) performed circle­drawing and freely improvised hand movement mirroring tasks in dyads. The participants were standing face­to­face, right index fingers pointed at each other, fingertips 10–15 cm apart. In turn, one of the participants was appointed the leader, or the dyad was instructed to share leadership. Hand movements were recorded using an optical motion capture system. Joint leadership resulted in smoother performances than the leader–follower condition; the follower participant would often hesitate or correct their movements, resulting in oscillatory 2–3 Hz jitter. In joint leadership tasks this jitter was 23% lower than in followers (p < 0.01). This corresponds with the “co­confident motion” observed in joint leadership mirror task by Noy et al. (2011). In leader­follower tasks the follower trailed the leader by approximately 0.3 seconds. Joint leadership trials resulted in mutual adaptation, with both participants “following” each other at similar lags. Windowed analysis revealed that the direction of the lag varied at sub­second intervals. Hand movements were faster in circle drawing than in free improvisation, but there were no velocity differences between the leadership conditions. These findings imply that dyads that share leadership perform smoother movements and exhibit stronger mutual adaptation than dyads where one participant is externally assigned as the leader. Our study on coordination of three­dimensional movements extends the scope of previous dyadic interaction studies that used rhythmic tapping and 1D movements.
Mot(s) clés libre(s) : interaction linguistique, improvisation

Is Europe becoming Asia ? Chair : Antoinette Fauve-Chamoux (EHESS) Speakers: Helena Hirata (CNRS) Care work in a comparative perspective: societal models, contexts, influences. Barbara Hobson (Stockholm University) Within, Beneath and Beyond the State: A Multi-dimensional Approach to Fathers’ Capabilities and Agency for Worklife Balance 
Mot(s) clés libre(s) : transformation, Asie, care, sociologie de la famille