Coordinating Joint Action in a Real-Life Activity

Humans engage in joint actions on a daily basis. Some of these joint actions are explicitly coordinated using, for example, speech and gesture, and the others are implicitly coordinated with the actions themselves. The first chapter of this dissertation reviews the use of speech, gesture, and intentional behavioral signals in explicit coordination of joint action and identifies three cognitive mechanisms that enable implicit coordination of joint action, namely, motor resonance, joint intentionality, and environmental and social affordance. The second chapter reports an empirical study exploring the employment of explicit and implicit coordination of joint action in a complex real-life joint activity, assembling a TV cart from its parts. We coded the content of the utterances and gestures that pairs of participants used throughout the assembly and the major and subordinate joint actions they performed. We then coded how each joint action was coordinated, that is, using speech, gestures, or action itself. The results showed speech and gesture served primarily to establish and sustain a shared mental model of the environmental affordances between the co-actors, which occurred primari