The role of object motion in visuo-haptic exploration during development

Since infancy we explore novel objects to infer their shape. However, how exploration strategies are planned to combine different sensory inputs is still an open question. In this work we focus on the development of visuo-haptic exploration strategies, by analyzing how school-aged children explore iCube, a sensorized cube measuring its orientation in space and contacts location. Participants' task was to find specific cube faces while they could either only touch the static cube (tactile), move and touch it (haptic) or move, touch and look at it (visuo-haptic). Visuo-haptic performances were adult-like at 7 years of age, whereas haptic exploration was not as effective until 9 years. Moreover, the possibility to rotate the object represented a difficulty rather than an advantage for the youngest age group. These findings are discussed in relation to the development of visuo-haptic integration and in the perspective of enabling early anomalies detection in explorative behaviors.