Humans Can’t Resist Robot Eyes – Reflexive Cueing With Pseudo-Social Stimuli

Abstract

Joint attention is a key mechanism for humans to coordinate their social behavior. Whether and how this mechanism can benefit the interaction with pseudo-social partners such as robots is not well understood. To investigate the potential use of robot eyes as pseudo-social cues that ease attentional shifts we conducted an online study using a modified spatial cueing paradigm. The cue was either a non-social (arrow), a pseudo-social (two versions of an abstract robot eye), or a social stimulus (photographed human eyes) that was presented either paired (e.g. two eyes) or single (e.g. one eye). The latter was varied to separate two assumed triggers of joint attention: the social nature of the stimulus, and the additional spatial information that is conveyed only by paired stimuli. Results support the assumption that pseudo-social stimuli, in our case abstract robot eyes, have the potential to facilitate human-robot interaction as they trigger reflexive cueing. To our surprise, actual social cues did not evoke reflexive shifts in attention. We suspect that the robot eyes elicited the desired effects because they were human-like enough while at the same time being much easier to perceive than human eyes, due to a design with strong contrasts and clean lines. Moreover, results indicate that for reflexive cueing it does not seem to make a difference if the stimulus is presented single or paired. This might be a first indicator that joint attention depends rather on the stimulus’ social nature or familiarity than its spatial expressiveness. Overall, the study suggests that using paired abstract robot eyes might be a good design practice for fostering a positive perception of a robot and to facilitate joint attention as a precursor for coordinated behavior.

The potential of robot eyes as predictive cues in HRI—an eye-tracking study

“…Moreover, the measurement of attention was only realized via covert measures in terms of reaction times. Thus, to further strengthen results and the interpretation that abstract anthropomorphic eyes induce reflexive gaze cueing, the aim of the current study was therefore to validate findings of the previous online study (Onnasch et al, 2022) in a highly controlled laboratory environment and to further deepen insights by introducing direct attentional measures via eye-tracking. We investigated how the design of highly abstract anthropomorphic eyes for a potential use on a collaborative robot should look like in order to reflexively trigger attention reallocation to improve the prediction of robot motion.…”

“…1,000 ms later the gaze averted to a position where the target appeared after a stimulus onset asynchrony (SOA) of 420 ms,. The target disappeared upon participants' reaction or a time-out of 2000 ms (description taken from Onnasch et al, 2022).…”

“…Whether abstract anthropomorphic eyes like robot eyes, trigger joint attention has therefore been the subject of several studies, which point to a great potential (Admoni and Scassellati, 2017). People have no problems reliably following a robot's gaze (e.g., Wiese et al, 2018;Onnasch et al, 2022), and use it to predict target positions before these are verbalized (Boucher et al, 2012). Even people's decision-making can be influenced by a robot's gaze.…”

“…According to these requirements, we investigated in a previous study directional stimuli differing in their degree of anthropomorphism to facilitate attentional shifts for the potential use as robot eyes on an industrial robot (Onnasch et al, 2022). The online study used a modified version of the spatial cueing paradigm (Posner, 1980), using either arrows, abstract anthropomorphic eyes or photographed human eyes as directional stimuli.…”

Effects of predictive robot eyes on attentional processes in HRI

“…However, it is still unclear to what extent automatic, i.e. reflexive attentional shifts are triggered by anthropomorphic robot eyes (Onnasch et al, 2022;Admoni et al, 2011). The aim of the current study therefore was to investigate in a highly controlled experiment what the design of eyes for the use on a collaborative robot should look like in order to reflexively trigger attention reallocation, hence improving the prediction of robotic motion.…”