Gaze-following Behavior Research Articles

A dual mobile eye tracking study on natural eye contact during live interactions

Human eyes convey a wealth of social information, with mutual looks representing one of the hallmark gaze communication behaviors. However, it remains relatively unknown if such reciprocal communication requires eye-to-eye contact or if general face-to-face looking is sufficient. To address this question, while recording looking behavior in live interacting dyads using dual mobile eye trackers, we analyzed how often participants engaged in mutual looks as a function of looking towards the top (i.e., the Eye region) and bottom half of the face (i.e., the Mouth region). We further examined how these different types of mutual looks during an interaction connected with later gaze-following behavior elicited in an individual experimental task. The results indicated that dyads engaged in mutual looks in various looking combinations (Eye-to-eye, Eye-to-mouth, and Mouth-to-Mouth) but proportionately spent little time in direct eye-to-eye gaze contact. However, the time spent in eye-to-eye contact significantly predicted the magnitude of later gaze following response elicited by the partner’s gaze direction. Thus, humans engage in looking patterns toward different face parts during interactions, with direct eye-to-eye looks occurring relatively infrequently; however, social messages relayed during eye-to-eye contact appear to carry key information that propagates to affect subsequent individual social behavior.

Atypical gaze-following behaviour in infants with congenital heart disease

BackgroundNeurodevelopmental impairments are the most prevalent non-cardiac long-term sequelae in children with complex congenital heart disease (CHD). Deficits include the social-emotional and social-cognitive domains. Little is known about the predecessors of social-cognitive development in infants with CHD during the first year of life. Gaze-following behaviour can be used to measure early social-cognitive abilities. AimsTo assess gaze-following development in infants with CHD compared to healthy controls. Study designProspective cohort study. ParticipantsTwenty-three infants who underwent neonatal correction for CHD and 84 healthy controls. Outcome measuresGaze-following behaviour was assessed by eye tracking at 6 and 12 months. Difference scores for first fixation, fixation frequency and fixation duration towards the gaze-cued object were calculated across 6 trials and compared between groups at both testing time points while adjusting for known confounders. Linear mixed models were calculated to assess the longitudinal trajectory of gaze-following development while accounting for the nested and dependent data structure. ResultsAt 6 months, no difference in gaze-following behaviour between CHD and healthy controls was found. At 12 months, fixation frequency towards the gaze-cued was lower and looking duration was shorter in CHD compared to controls (p = 0.0077; p = 0.0068). Infants with CHD showed less increase with age in the fixation frequency towards the congruent object (p = 0.041) compared to controls. ConclusionDuring the first year of life, gaze-following development diverges in infants with CHD compared to healthy controls. Further research is needed to investigate the clinical relevance of these findings and the association with later social-cognitive development.

Can masked gaze and arrow stimuli elicit overt orienting of attention? A registered report

Viewing an averted gaze can elicit saccades towards the corresponding location. Here, the automaticity of this gaze-following behaviour phenomenon was further tested by exploring whether such an effect can be detected in response to briefly-presented masked averted gazes. Participants completed an oculomotor interference task consisting of making leftward/rightward saccades according to a symbolic instruction cue. Crucially, either a task-irrelevant averted-gaze face or an arrow (i.e., a non-social control stimulus) was also presented in different blocks of trials. Faces and arrows were presented for either 1000 ms, or 8 ms and then backward-masked, to reduce the likelihood of conscious processing. Worse oculomotor performance emerged when the saccade direction did not match (vs match) that suggested by the task-irrelevant gaze/arrow stimuli in the unmasked condition. However, in the masked condition, no oculomotor interference occurred for any task-irrelevant stimulus. Results enrich knowledge about boundary conditions for gaze/arrow-driven orienting using ecological attention measures.

How experience shapes infants' communicative behaviour: Comparing gaze following in infants with and without pandemic experience.

The COVID-19 pandemic has been influencing people's social life substantially. Everybody, including infants and children needed to adapt to changes in social interactions (e.g., social distancing) and to seeing other people wearing facial masks. In this study, we investigated whether these pandemic-related changes influenced 12- to 15-months-old infants' reactions to observed gaze shifts (i.e., their gaze following). In two eye-tracking tasks, we measured infants' gaze-following behavior during the pandemic (with-COVID-19-experience sample) and compared it to data of infants tested before the pandemic (no-COVID-19-experience sample). Overall, the results indicated no significant differences between the two samples. However, in one sub-task infants in the with-COVID-19-experience sample looked longer at the eyes of a model compared to the no-COVID-19-experience sample. Within the with-COVID-19-experience sample, the amount of mask exposure and the number of contacts without mask were not related to infants' gaze-following behavior. We speculate that even though infants encounter fewer different people during the pandemic and are increasingly exposed to people wearing facial masks, they still also see non-covered faces. These contacts might be sufficient to provide infants with the social input they need to develop social and emotional competencies such as gaze following.

Automatic classification of children with autism spectrum disorder by using a computerized visual-orienting task.

Early screening and diagnosis of autism spectrum disorder (ASD) primarily rely on behavioral observations by qualified clinicians whose decision process can benefit from the combination of machine learning algorithms and sensor data. We designed a computerized visual-orienting task with gaze-related or non-gaze-related directional cues, which triggered participants' gaze-following behavior. Based on their eye-movement data registered by an eye tracker, we applied the machine learning algorithms to classify high-functioning children with ASD (HFA), low-functioning children with ASD (LFA), and typically developing children (TD). We found that TD children had higher success rates in obtaining rewards than HFA children, and HFA children had higher rates than LFA children. Based on raw eye-tracking data, our machine learning algorithm could classify the three groups with an accuracy of 81.1% and relatively high sensitivity and specificity. Classification became worse if only data from the gaze or nongaze conditions were used, suggesting that "less-social" directional cues also carry useful information for distinguishing these groups. Our findings not only provide insights about visual-orienting deficits among children with ASD but also demonstrate the promise of combining classical behavioral paradigms with machine learning algorithms for aiding the screening for individuals with ASD.

Social categorization and joint attention: Interacting effects of age, sex, and social status

In the present study, we examine how person categorization conveyed by the combination of multiple cues modulates joint attention. In three experiments, we tested the combinatory effect of age, sex, and social status on gaze-following behaviour and pro-social attitudes. In Experiments 1 and 2, young adults were required to perform an instructed saccade towards left or right targets while viewing a to-be-ignored distracting face (female or male) gazing left or right, that could belong to a young, middle-aged, or elderly adult of high or low social status. Social status was manipulated by semantic knowledge (Experiment 1) or through visual appearance (Experiment 2). Results showed a clear combinatory effect of person perception cues on joint attention (JA). Specifically, our results showed that age and sex cues interacted with social status information depending on the modality through which it was conveyed. In Experiment 3, we further investigated our results by testing whether the identities used in Experiments 1 and 2 triggered different pro-social behaviour. The results of Experiment 3 showed that the identities resulting as more distracting in Experiments 1 and 2 were also perceived as more in need and prompt helping behaviour. Taken together, our evidence shows a combinatorial effect of age, sex, and social status in modulating the gaze following behaviour, highlighting a complex and dynamic interplay between person categorization and joint attention.

Gaze towards my choice: Noneconomic social interaction changes interpersonal trust only with positive feedback.

Trust is a crucial foundation of human society, dynamically changing along with interpersonal interactions. Previous research suggested that both gaze behaviors and affective states might influence our trust evaluation. Here, we created an uncertain decision-making environment to investigate how these two aspects change interpersonal trust during social interactions. Specifically, participants made a forced choice between two price-matched goods to determine which one was more expensive. After participants made a choice, the face in the center of the screen would gaze towards or away from the participants' choice, and then participants would receive timely feedback informing whether their choice was correct or not. In Experiment 1 (N = 34), we found people increased their trust ratings for gaze-followers but reduced them for gaze-unfollowers when they received positive feedback, but stayed with their initial judgments when receiving negative feedback. Experiment 2 (N = 20) and Experiment S1 (N = 20) further revealed the same change patterns on participants' trust investments in different conditions. These results suggest that gaze-following behavior can change people's trust evaluations as well as trust behaviors, while affective states induced by different feedback modulate this process in a flexible manner.

Early saccade planning cannot override oculomotor interference elicited by gaze and arrow distractors.

Humans tend to perform reflexive saccades according to the eye-gaze direction of other individuals. Here, in two experiments, we tested whether preparing a saccade before the onset of a task-irrelevant averted-gaze stimulus can abolish this form of gaze-following behavior. At the beginning of each trial, participants received the instruction to prepare for a leftward or a rightward saccade. This was provided either on a trial-by-trial basis (Experiment 1) or was maintained constant within a whole block of trials (Experiment 2). Then, a central fixation spot changed in color, acting as a "go" signal to perform the saccade. Simultaneously with the go-signal onset, a task-irrelevant distractor face looked either leftwards or rightwards. In so doing, no temporal overlapping was likely to occur between saccade preparation and the presentation of the distractor. Arrows were also employed as non-social control stimuli. In both experiments - and regardless of the distractor type - saccadic latencies were smaller when both the instruction and the distractor conveyed the same spatial vector, rather than the opposite. Taken together, these results suggest that an early preparation of saccades is not sufficient to override the oculomotor interference effects elicited by both social and non-social distractors.

Learning Process of Gaze Following: Computational Modeling Based on Reinforcement Learning.

Many studies have explored factors which influence gaze-following behavior of young infants. However, the results of empirical studies were inconsistent, and the mechanism underlying the contextual modulation of gaze following remains unclear. In order to provide valuable insight into the mechanisms underlying gaze following, we conducted computational modeling using Q-learning algorithm and simulated the learning process of infant gaze following to suggest a feasible model. In Experiment 1, we simulated how communicative cues and infant internal states affect the learning process of gaze following. The simulation indicated that the model in which communicative cues enhance infant internal states is the most feasible to explain the infant learning process. In Experiment 2, we simulated how individual differences in motivation for communication affect the learning process. The results showed that low motivation for communication can delay the learning process and decrease the frequency of gaze following. These simulations suggest that communicative cues may enhance infants’ internal states and promote the development of gaze following. Also, initial social motivation may affect the learning process of social behaviors in the long term.

Ostension affects infant learning more than attention

A recent controversy in infants’ social learning has revolved around whether ostensive cues have an effect beyond simply grabbing infants’ attention: natural pedagogy theory vs. attention modulation theory. However, since previous research only focused on gaze-following behaviors, it has failed to determine whether attention-grabbing versus ostensive cues might affect infants’ learning at different levels. To explore this possibility, we conducted a critical test with 9-month-old infants (N=140) in which gaze-following behavior was discriminated from referential learning about a target object (object processing and object preference). Here we report that although both attentional cues (shivering, a beep, and mouth-moving beep) and ostensive cues (infant-directed speech) affected infants’ gaze-following, only ostensive cues facilitated their referential object learning. These findings provide new evidence that ostensive cues play a distinct role in infant learning, supporting natural pedagogy theory.

Attention to faces and gaze-following in social anxiety: preliminary evidence from a naturalistic eye-tracking investigation

ABSTRACTSocial attentional biases are a core component of social anxiety disorder, but research has not yet determined their direction due to methodological limitations. Here we present preliminary findings from a novel, dynamic eye-tracking paradigm allowing spatial–temporal measurement of attention and gaze-following, a mechanism previously unexplored in social anxiety. 105 participants took part, with those high (N = 27) and low (N = 25) in social anxiety traits (HSA and LSA respectively) entered into the analyses. Participants watched a video of an emotionally-neutral social scene, where two actors periodically shifted their gaze towards the periphery. HSA participants looked more at the actors’ faces during the initial 2s than the LSA group but there were no group differences in proportion of first fixations to the face or latency to first fixate the face, although HSA individuals’ first fixations to the face were shorter. No further differences in eye movements were found, nor in gaze-following behaviour, although these null effects could potentially result from the relatively small sample. Findings suggest attention is biased towards faces in HSA individuals during initial scene inspection, but that overt gaze-following may be impervious to individual differences in social anxiety. Future research should seek to replicate these effects.

Robot Faces that Follow Gaze Facilitate Attentional Engagement and Increase Their Likeability.

Gaze behavior of humanoid robots is an efficient mechanism for cueing our spatial orienting, but less is known about the cognitive–affective consequences of robots responding to human directional cues. Here, we examined how the extent to which a humanoid robot (iCub) avatar directed its gaze to the same objects as our participants affected engagement with the robot, subsequent gaze-cueing, and subjective ratings of the robot’s characteristic traits. In a gaze-contingent eyetracking task, participants were asked to indicate a preference for one of two objects with their gaze while an iCub avatar was presented between the object photographs. In one condition, the iCub then shifted its gaze toward the object chosen by a participant in 80% of the trials (joint condition) and in the other condition it looked at the opposite object 80% of the time (disjoint condition). Based on the literature in human–human social cognition, we took the speed with which the participants looked back at the robot as a measure of facilitated reorienting and robot-preference, and found these return saccade onset times to be quicker in the joint condition than in the disjoint condition. As indicated by results from a subsequent gaze-cueing tasks, the gaze-following behavior of the robot had little effect on how our participants responded to gaze cues. Nevertheless, subjective reports suggested that our participants preferred the iCub following participants’ gaze to the one with a disjoint attention behavior, rated it as more human-like and as more likeable. Taken together, our findings show a preference for robots who follow our gaze. Importantly, such subtle differences in gaze behavior are sufficient to influence our perception of humanoid agents, which clearly provides hints about the design of behavioral characteristics of humanoid robots in more naturalistic settings.

Where Is Your Attention? Assessing Individual Instances of Covert Attentional Orienting in Response to Gaze and Arrow Cues.

Humans spontaneously follow where others are looking. However, recent investigations suggest such gaze-following behavior during natural interactions occurs relatively infrequently, only in about a third of available instances. Here we investigated if a similar frequency of orienting is also found in laboratory tasks that measure covert attentional orienting using manual responses. To do so, in two experiments, we analyzed responses from a classic gaze cuing task, with arrow cues serving as control stimuli. We reasoned that the proportions of attentional benefits and costs, defined as responses falling outside of 1 standard deviation of the average performance for the neutral condition, would provide a good approximation of individual instances of attentional shifts. We found that although benefits and costs occurred in less than half of trials, benefits emerged on a greater proportion of validly cued relative to invalidly cued trials. This pattern of data held across two different measures of neutral performance, as assessed by Experiments 1 and 2, as well as across the two cue types. These results suggest that similarly to gaze-following in naturalistic settings, covert orienting within the cuing task also appears to occur relatively infrequently.

Individual differences in object-processing explain the relationship between early gaze-following and later language development

Gaze-following behaviors play an important role in language development. However, the way in which gaze-following contributes to language development remains unclear. By focusing on two abilities, namely following the gaze direction of others and processing a cued object, the present study investigated how these two influences work together to promote language development in a longitudinal approach on infants from 9 to 18months of age. The results demonstrated that infants who spent more time following the gaze direction toward an object were more efficient in processing the cued object at 9months and had larger vocabularies by 18months. Mediation analyses showed that the relationship between early gaze-following behavior and subsequent vocabulary size was explained by object-processing ability. Importantly, mere extended fixations on a target object without the initiation of another’s gaze shift were not related to enhanced object-processing. Our findings suggest that following another’s gaze shift toward the object has an impact on object-processing that could contribute to vocabulary development, elucidating a critical step in the path from early gaze-following ability to later language development.

Can we resist another person's gaze?

Adaptive adjustments of strategies are needed to optimize behavior in a dynamic and uncertain world. A key function in implementing flexible behavior and exerting self-control is represented by the ability to stop the execution of an action when it is no longer appropriate for the environmental requests. Importantly, stimuli in our environment are not equally relevant and some are more valuable than others. One example is the gaze of other people, which is known to convey important social information about their direction of attention and their emotional and mental states. Indeed, gaze direction has a significant impact on the execution of voluntary saccades of an observer since it is capable of inducing in the observer an automatic gaze-following behavior: a phenomenon named social or joint attention. Nevertheless, people can exert volitional inhibitory control on saccadic eye movements during their planning. Little is known about the interaction between gaze direction signals and volitional inhibition of saccades. To fill this gap, we administered a countermanding task to 15 healthy participants in which they were asked to observe the eye region of a face with the eyes shut appearing at central fixation. In one condition, participants were required to suppress a saccade, that was previously instructed by a gaze shift toward one of two peripheral targets, when the eyes were suddenly shut down (social condition, SC). In a second condition, participants were asked to inhibit a saccade, that was previously instructed by a change in color of one of the two same targets, when a change of color of a central picture occurred (non-social condition, N-SC). We found that inhibitory control was more impaired in the SC, suggesting that actions initiated and stopped by social cues conveyed by the eyes are more difficult to withhold. This is probably due to the social value intrinsically linked to these cues and the many uses we make of them.

Perceived gaze direction modulates ad memorization.

Gaze has important functions in human social interactions. A direct gaze can be used to focus observer’s attention on a face, whereas an averted gaze can be used to direct observer’s attention to an object or a point in space. Several studies in neuroscience and psychology demonstrate the role of gaze direction not only in orienting observer’s attention but also in modulating his cognitive process. The detection of an averted gaze induces a shift of visual attention by means of reflexive gaze-following behavior. In marketing, little is known about gaze direction effect on ads’ content processing. This research presents recent findings on neural correlates of the processing of gaze direction and its influence on orienting observer’s visual attention. Then, using a folder test procedure, it investigates the influence of perceived gaze direction of a character in a print ad on product and brand memorization. Comparing 2 conditions—ads presenting a face with “averted gaze” toward the advertised product or “direct gaze” toward the observer—our results show that ad with gaze toward the product increases product and brand memorization. As these results were obtained by reproducing real-life conditions of ad processing—a folder magazine—we believe that they are of particular interest for managers, especially in an environmental context increasingly cluttered with advertising that marketers have to face nowadays. Further researches are needed to explore other effects of gaze direction in ads, such as for example the effects on advertising evaluation. (PsycINFO Database Record (c) 2015 APA, all rights reserved)

Amygdala: Eyes Wide Open

Summary A new study sheds light on how the amygdala contributes to social interactions by providing direct evidence for specialized visual neurons that selectively respond to seeing the eyes of another individual or making eye contact with them.

Gaze-following behind barriers in domestic dogs

Although gaze-following abilities have been demonstrated in a wide range of species, so far no clear evidence has been available for dogs. In the current study, we examined whether dogs follow human gaze behind an opaque barrier in two different contexts, in a foraging situation and in a non-foraging situation (food involved vs. food not involved in the situation). We assumed that dogs will spontaneously follow the human gaze and that the foraging context will have a positive effect on dogs' gaze-following behaviour by causing an expectation in the dogs that food might be hidden somewhere in the room and might be communicated by the experimenter. This expectation presumably positively affects their motivational and attentional state. Here, we report that dogs show evidence of spontaneous gaze-following behind barriers in both situations. According to our findings, the dogs gazed earlier at the barrier in the indicated direction in both contexts. However, as we expected, the context also has some effect on dogs' gaze-following behaviour, as more dogs gazed behind the barrier in the indicated direction in the foraging situation. The present results also support the idea that gaze-following is a characteristic skill in mammals which may more easily emerge in certain functional contexts.

Face age modulates gaze following in young adults.

Gaze-following behaviour is considered crucial for social interactions which are influenced by social similarity. We investigated whether the degree of similarity, as indicated by the perceived age of another person, can modulate gaze following. Participants of three different age-groups (18–25; 35–45; over 65) performed an eye movement (a saccade) towards an instructed target while ignoring the gaze-shift of distracters of different age-ranges (6–10; 18–25; 35–45; over 70). The results show that gaze following was modulated by the distracter face age only for young adults. Particularly, the over 70 year-old distracters exerted the least interference effect. The distracters of a similar age-range as the young adults (18–25; 35–45) had the most effect, indicating a blurred own-age bias (OAB) only for the young age group. These findings suggest that face age can modulate gaze following, but this modulation could be due to factors other than just OAB (e.g., familiarity).

Automated gaze-contingent objects elicit orientation following in 8-month-old infants.

The current study tested whether the purely amodal cue of contingency elicits orientation following behavior in 8-month-old infants. We presented 8-month-old infants with automated objects without human features that did or did not react contingently to the infants' fixations recorded by an eye tracker. We found that an object's occasional orientation toward peripheral targets was reciprocated by a congruent visual orientation following response by infants only when it had displayed gaze-contingent interactivity. Our finding demonstrates that infants' gaze-following behavior does not depend on the presence of a human being. The results are consistent with the idea that, in 8-month-old infants, the detection of contingent reactivity, like other communicative signals, can itself elicit the illusion of being addressed.