When Height Carries Weight: Communicating Hidden Object Properties for Joint Action

Abstract

In the absence of pre‐established communicative conventions, people create novel communication systems to successfully coordinate their actions toward a joint goal. In this study, we address two types of such novel communication systems: sensorimotor communication, where the kinematics of instrumental actions are systematically modulated, versus symbolic communication. We ask which of the two systems co‐actors preferentially create when aiming to communicate about hidden object properties such as weight. The results of three experiments consistently show that actors who knew the weight of an object transmitted this weight information to their uninformed co‐actors by systematically modulating their instrumental actions, grasping objects of particular weights at particular heights. This preference for sensorimotor communication was reduced in a fourth experiment where co‐actors could communicate with weight‐related symbols. Our findings demonstrate that the use of sensorimotor communication extends beyond the communication of spatial locations to non‐spatial, hidden object properties.

Informing, Coordinating, and Performing: A Perspective on Functions of Sensorimotor Communication

“…This in turn, allowed them to be more synchronized. Other action features besides movement amplitude are modulated for communication, including grasp position on an object (Schmitz et al, 2018), grasp aperture while moving towards an object (Sacheli et al, 2013), and the speed with which to approach a target location (Vesper et al, 2017b).…”

Expression Unleashed: The evolutionary & cognitive foundations of human communication

“…Such behaviours are forms of 'coordination smoother', and are increasingly discussed and studied in informational terms (e.g. McEllin 7 Schmitz et al, 2018;Curioni et al, 2019;Pezzulo et al, 2019). However it is presently unclear whether and how this means of informing others is related to others discussed in this article.…”

Understanding others’ distal goals from proximal communicative actions

“…In the case of SMC, the relevant similarity is established between a particular movement used by the sender and the most likely goal that such movement achieves during natural performance. For example, a higher movement trajectory communicates a higher final grasp location [12]-because higher grasping movements are naturally performed with higher movement amplitude (also see [37]). A similar observation regarding the similarity between communicative movements and their goals has been made by researchers in sign language, who have argued that verbs in American Sign Language (ASL) used to refer to the manipulation of a tool (i.e., so-called handling classifier verbs such as BRUSH-HAIR or BOUNCE--BALL) are represented "motor-iconically" with a handshape that depicts how a person grasps and manipulates the tool, as well as the movements typically performed with it (e.g., brushing one's hair or bouncing a ball) [38].…”