ABSTRACT
This study aims to determine if, in children, subjective perception of space is modulated by the experience of reaching distal objects by means of tools and verbal labels. We presented 7–15-year-old participants with objects located in the near and far space, and in the threshold area between these spaces (border space). Before and after a training session, separate groups of participants estimated objects' location by providing a verbal estimation of their distance (n = 12) or by rolling a toy car to match their location (motor-based estimation; n = 16). The training session required interaction with the targets (i.e., actively experiencing the perceived distance) and included use of a rake or a linguistic label when far objects were involved. A control condition in which training implied use of a short, ineffective tool was also tested (n = 6). Results showed that verbal estimations were not affected by the training phase (p > .05). In contrast, training modulated motor-based estimations relative to border space. Specifically, maximal distance of toy car displacements was reduced following all kinds of training (p < .01). These results indicate that, similarly to adults, the boundary between near and far space is not fixed in children and that both active tool use and verbal labels can modulate this uncertain boundary.
ACKNOWLEDGMENTS
The authors thank Prof. Roberto Bolzani for statistical advice, Andrea Flumini for the help in conducting the experiments, and Michele Marzocchi for the script to export the kinematics analyses. They also thank the anonymous reviewers for comments on a previous version of the work. Finally, they thank the children who patiently participated to the experiments.
Funding
This work was supported by the European Community, project ROSSI: Emergence of communication in RObots through Sensorimotor and Social Interaction (Grant agreement no. 216125).