The effect of non-communicative eye movements on joint attention.

Nathan Caruana,Genevieve Mcarthur,Ayeh Alhasan,Kirilee Wagner,David M Kaplan,Alexandra Woolgar

doi:10.1177/1747021820945604

Abstract

Eye movements provide important signals for joint attention. However, those eye movements that indicate bids for joint attention often occur among non-communicative eye movements. This study investigated the influence of these non-communicative eye movements on subsequent joint attention responsivity. Participants played an interactive game with an avatar which required both players to search for a visual target on a screen. The player who discovered the target used their eyes to initiate joint attention. We compared participants’ saccadic reaction times (SRTs) to the avatar’s joint attention bids when they were preceded by non-communicative eye movements that predicted the location of the target (Predictive Search), did not predict the location of the target (Random Search), and when there were no non-communicative eye gaze movements prior to joint attention (No Search). We also included a control condition in which participants completed the same task, but responded to a dynamic arrow stimulus instead of the avatar’s eye movements. For both eye and arrow conditions, participants had slower SRTs in Random Search trials than No Search and Predictive Search trials. However, these effects were smaller for eyes than for arrows. These data suggest that joint attention responsivity for eyes is relatively stable to the presence and predictability of spatial information conveyed by non-communicative gaze. Contrastingly, random sequences of dynamic arrows had a much more disruptive impact on subsequent responsivity compared with predictive arrow sequences. This may reflect specialised social mechanisms and expertise for selectively responding to communicative eye gaze cues during dynamic interactions, which is likely facilitated by the integration of ostensive eye contact cues.

Highlights

Navigating social interactions depends on a range of cognitive abilities, including joint attention which is the process by which we coordinate attention to share information with others
This study shows that joint attention responsivity is influenced by the presence and predictability of non-communicative eye movements made by a social partner before a joint attention bid
Responsivity to gaze-cued joint attention is relatively stable when compared with responsivity to dynamic arrow cues in matched task contexts, where participants demonstrate significantly larger costs in response times when there is a need to parse and disregard irrelevant and non-predictive spatial information

Summary

Introduction

Navigating social interactions depends on a range of cognitive abilities, including joint attention which is the process by which we coordinate attention to share information with others. Of critical importance to this study, this paradigm—unlike noninteractive gaze cueing paradigms—provides a dynamic mix of non-communicative and communicative eye gaze behaviours which participants must continuously evaluate and intentionally respond to in order to coordinate with their social partner (see Caruana, McArthur, Woolgar, & Brock, 2017, for an in-depth discussion and review of this approach). Our gaze-contingent algorithm ensures that Alan completes his search after the participant, so that once the participant fixates on Alan’s face, he searches 1–2 more houses before establishing eye contact This ensured that participants attend to Alan’s non-communicative and communicative eye gaze behaviours and allowed us to manipulate the presence and predictability of non-communicate gaze cues. Is it the case that all types of non-communicative eye movements are harmful to joint attention responses? Or could some types of non-communicative eye movements enhance the ability to respond to joint attention bids?

Results

Discussion

Conclusion