Twelve-month-old infants’ attention to the eyes of a talking face is associated with communication and social skills

We investigated whether attention to a talker’s eyes in 12 month-old infants is related to their communication and social abilities. We measured infant attention to a talker’s eyes and mouth with a Tobii eye-tracker and examined the correlation between attention to the talker’s eyes and scores on the Adaptive Behavior Questionnaire from the Bayley Scales of Infant and Toddler Development (BSID-III). Results indicated a positive relationship between eye gaze and scores on the Social and Communication subscales of the BSID-III.     

A study of artificial eyes for the measurement of precision in eye-trackers

The precision of an eye-tracker is critical to the correct identification of eye movements and their properties. To measure a system’s precision, artificial eyes (AEs) are often used, to exclude eye movements influencing the measurements. A possible issue, however, is that it is virtually impossible to construct AEs with sufficient complexity to fully represent the human eye. To examine the consequences of this limitation, we tested currently used AEs from three manufacturers of eye-trackers and compared them to a more complex model, using 12 commercial eye-trackers. Because precision can be measured in various ways, we compared different metrics in the spatial domain and analyzed the power-spectral densities in the frequency domain. To assess how precision measurements compare in artificial and human eyes, we also measured precision using human recordings on the same eye-trackers. Our results show that the modified eye model presented can cope with all eye-trackers tested and acts as a promising candidate for further development of a set of AEs with varying pupil size and pupil–iris contrast. The spectral analysis of both the AE and human data revealed that human eye data have different frequencies that likely reflect the physiological characteristics of human eye movements. We also report the effects of sample selection methods for precision calculations. This study is part of the EMRA/COGAIN Eye Data Quality Standardization Project.     

Motion influences gaze direction discrimination and disambiguates contradictory luminance cues

In two experiments, we investigated the role of apparent motion in discriminating left/right gaze deviation judgments. We demonstrated that discrimination accuracy and response confidence was significantly higher when the eyes were moved to the left or right, compared to when the eyes were presented in their final shifted position (static images). To dissociate the role of motion signals from luminance signals, gaze stimuli were also presented in reverse contrast. Replicating past studies polarity reversal had a profound and detrimental effect on gaze discrimination in static images, although, intriguingly, while response confidence remained low, participant performance improved as gaze angle increased. In striking contrast to these data, polarity reversal had no negative effect on performance when the eyes were moved. We discuss these findings in the context of a multiple-cue account of gaze perception.     

Limitations of gaze transfer: Without visual context,eye movements do not to help to coordinate joint action,whereas mouse movements do

Remote cooperation can be improved by transferring the gaze of one participant to the other. However, based on a partner's gaze, an interpretation of his communicative intention can be difficult. Thus, gaze transfer has been inferior to mouse transfer in remote spatial referencing tasks where locations had to be pointed out explicitly. Given that eye movements serve as an indicator of visual attention, it remains to be investigated whether gaze and mouse transfer differentially affect the coordination of joint action when the situation demands an understanding of the partner's search strategies. In the present study, a gaze or mouse cursor was transferred from a searcher to an assistant in a hierarchical decision task. The assistant could use this cursor to guide his movement of a window which continuously opened up the display parts the searcher needed to find the right solution. In this context, we investigated how the ease of using gaze transfer depended on whether a link could be established between the partner's eye movements and the objects he was looking at. Therefore, in addition to the searcher's cursor, the assistant either saw the positions of these objects or only a grey background. When the objects were visible, performance and the number of spoken words were similar for gaze and mouse transfer. However, without them, gaze transfer resulted in longer solution times and more verbal effort as participants relied more strongly on speech to coordinate the window movement. Moreover, an analysis of the spatio-temporal coupling of the transmitted cursor and the window indicated that when no visual object information was available, assistants confidently followed the searcher's mouse but not his gaze cursor. Once again, the results highlight the importance of carefully considering task characteristics when applying gaze transfer in remote cooperation.     

光标显示模式对视线交互绩效与用户体验的影响研究

显示与反馈方式是人机交互的重要设计要素。在视线交互这种自然人机交互技术中,视线光标的呈现方式一直是研究的焦点。本研究选取基于凝视点击范式的文本输入任务,设计了2（有无视点锁定功能）×2（有无实时注视点）被试内实验,探讨光标显示模式对视线交互绩效与用户体验的影响。结果：视点锁定功能可以提升交互绩效和用户体验,有无实时注视点对交互绩效无显著影响;输入速度的提升主要在于视点锁定功能能够让被试的视线更快地转移到下一个目标上。研究结果可为视线光标的设计与应用提供借鉴。     

Affect in the eyes: explicit and implicit evaluations

The present study investigated whether another individual’s gaze direction influences an observer’s affective responses. In Experiment 1, subjective self-ratings and an affective priming paradigm were employed to examine how participants explicitly and implicitly, respectively, evaluated the affective valence of direct gaze, averted gaze, and closed eyes. The explicit self-ratings showed that participants evaluated closed eyes more positively than direct gaze. However, the implicit priming task showed an inverse pattern of results indicating that direct gaze was automatically evaluated more positively than closed eyes were. Experiment 2 confirmed that the opposite patterns of results between the two tasks were not due to differences in presentation times of the gaze stimuli. The results provide evidence for automatic affective reactions to eye gaze and indicate a dissociation between explicit and implicit affective evaluations of eyes and gaze direction.     

Gaze step distributions reflect fixations and saccades: a comment on

In three experimental tasks Stephen and Mirman (2010) measured gaze steps, the distance in pixels between gaze positions on successive samples from an eyetracker. They argued that the distribution of gaze steps is best fit by the lognormal distribution, and based on this analysis they concluded that interactive cognitive processes underlie eye movement control in these tasks. The present comment argues that the gaze step distribution is predictable based on the fact that the eyes alternate between a fixation state in which gaze is steady and a saccade state in which gaze position changes rapidly. By fitting a simple mixture model to Stephen and Mirman's gaze step data we reveal a fixation distribution and a saccade distribution. This mixture model captures the shape of the gaze step distribution in detail, unlike the lognormal model, and provides a better quantitative fit to the data. We conclude that the gaze step distribution does not directly suggest processing interaction, and we emphasize some important limits on the utility of fitting theoretical distributions to data.     

The influence of calibration method and eye physiology on eyetracking data quality

Recording eye movement data with high quality is often a prerequisite for producing valid and replicable results and for drawing well-founded conclusions about the oculomotor system. Today, many aspects of data quality are often informally discussed among researchers but are very seldom measured, quantified, and reported. Here we systematically investigated how the calibration method, aspects of participants’ eye physiologies, the influences of recording time and gaze direction, and the experience of operators affect the quality of data recorded with a common tower-mounted, video-based eyetracker. We quantified accuracy, precision, and the amount of valid data, and found an increase in data quality when the participant indicated that he or she was looking at a calibration target, as compared to leaving this decision to the operator or the eyetracker software. Moreover, our results provide statistical evidence of how factors such as glasses, contact lenses, eye color, eyelashes, and mascara influence data quality. This method and the results provide eye movement researchers with an understanding of what is required to record high-quality data, as well as providing manufacturers with the knowledge to build better eyetrackers.     

Looking at others through implicitly or explicitly prejudiced eyes

It is well known that we utilize internalized representations (or schemas) to direct our eyes when exploring visual stimuli. Interestingly, our schemas for human faces are known to reflect systematic differences that are consistent with one's level of racial prejudice. However, whether one's level or type of racial prejudice can differentially regulate how we visually explore faces that are the target of prejudice is currently unknown. Here, White participants varying in their level of implicit or explicit prejudice viewed Black faces and White faces (with the latter serving as a control) while having their gaze behaviour recorded with an eye-tracker. The results show that, regardless of prejudice type (i.e., implicit or explicit), participants high in racial prejudice examine faces differently than those low in racial prejudice. Specifically, individuals high in explicit racial prejudice were more likely to fixate on the mouth region of Black faces when compared to individuals low in explicit prejudice, and exhibited less consistency in their scanning of faces irrespective of race. On the other hand, individuals high in implicit racial prejudice tended to focus on the region between the eyes, regardless of face race. It therefore seems that racial prejudice guides target-race specific patterns of looking behaviour, and may also contribute to general patterns of looking behaviour when visually exploring human faces.     

Noise-robust fixation detection in eye movement data: Identification by two-means clustering (I2MC)

Eye-tracking research in infants and older children has gained a lot of momentum over the last decades. Although eye-tracking research in these participant groups has become easier with the advance of the remote eye-tracker, this often comes at the cost of poorer data quality than in research with well-trained adults (Hessels, Andersson, Hooge, Nyström, & Kemner Infancy, 20, 601–633, 2015; Wass, Forssman, & Leppänen Infancy, 19, 427–460, 2014). Current fixation detection algorithms are not built for data from infants and young children. As a result, some researchers have even turned to hand correction of fixation detections (Saez de Urabain, Johnson, & Smith Behavior Research Methods, 47, 53–72, 2015). Here we introduce a fixation detection algorithm—identification by two-means clustering (I2MC)—built specifically for data across a wide range of noise levels and when periods of data loss may occur. We evaluated the I2MC algorithm against seven state-of-the-art event detection algorithms, and report that the I2MC algorithm’s output is the most robust to high noise and data loss levels. The algorithm is automatic, works offline, and is suitable for eye-tracking data recorded with remote or tower-mounted eye-trackers using static stimuli. In addition to application of the I2MC algorithm in eye-tracking research with infants, school children, and certain patient groups, the I2MC algorithm also may be useful when the noise and data loss levels are markedly different between trials, participants, or time points (e.g., longitudinal research).     

线索类型对阈下注视线索效应的影响

实验结合连续闪烁抑制范式和线索化范式, 通过操纵直视面孔和斜视面孔的呈现方式, 考察了动静线索类型对注视线索效应的影响。结果表明：两种线索在阈上条件都能产生注视线索效应, 且动态线索诱发的效应更大; 无意识条件下有且仅有动态注视线索能诱发注视线索效应。这说明眼睛运动是产生阈下注视线索效应的必要条件; 眼睛运动会增强阈上注视线索效应, 静态注视线索效应依赖于意识。研究结果支持了社会知觉与心理理论交互模型。     

The whereabouts of visual attention: Involuntary attentional bias toward the default gaze direction

This study proposed and verified a new hypothesis on the relationship between gaze direction and visual attention: attentional bias by default gaze direction based on eye-head coordination. We conducted a target identification task in which visual stimuli appeared briefly to the left and right of a fixation cross. In Experiment 1, the direction of the participant’s head (aligned with the body) was manipulated to the left, front, or right relative to a central fixation point. In Experiment 2, head direction was manipulated to the left, front, or right relative to the body direction. This manipulation was based on results showing that bias of eye position distribution was highly correlated with head direction. In both experiments, accuracy was greater when the target appeared at a position where the eyes would potentially be directed. Consequently, eye–head coordination influences visual attention. That is, attention can be automatically biased toward the location where the eyes tend to be directed.     

Arrows don’t look at you: Qualitatively different attentional mechanisms triggered by gaze and arrows

Eye gaze conveys rich information concerning the states of mind of others, playing a critical role in social interactions, signaling internal states, and guiding others’ attention. On the basis of its social significance, some researchers have proposed that eye gaze may represent a unique attentional stimulus. However, contrary to this notion, the majority of the literature has shown indistinguishable attentional effects when eye gaze and arrows have been used as cues. Taking a different approach, in this study we aimed at finding qualitative attentional differences between gazes and arrows when they were used as targets instead of as cues. We used a spatial Stroop task, in which participants were required to identify the direction of eyes or arrows presented to the left or the right of a fixation point. The results showed that the two types of stimuli led to opposite spatial interference effects, with arrows producing faster reaction times when the stimulus direction was congruent with the stimulus position (a typical spatial Stroop effect), and eye gaze producing faster reaction times when it was incongruent (a “reversed” spatial Stroop effect). This reversed Stroop is interpreted as an eye-contact effect, therefore revealing the unique nature of eyes as special social-attention stimuli.     

Straight gaze facilitates face processing but does not cause involuntary attentional capture

This study aimed to investigate the conditions under which eyes with a straight gaze capture attention more than eyes with an averted gaze, a phenomenon called the stare-in-the-crowd effect. In Experiment 1, we measured attentional capture by distractor faces with either straight or averted gaze that were shown among faces with closed eyes. Gaze direction of the distractor face was irrelevant because participants searched for a tilted face and indicated its gender. The presence of the distractor face with open eyes resulted in slower reaction times, but gaze direction had no effect, suggesting that straight gaze does not result in more involuntary attentional capture than averted gaze. In three further experiments with the same stimuli, the gaze direction of the target, and not the distractor, was varied. Better performance with straight than averted gaze of the target face was observed when the gaze direction or gender of the target face had to be discriminated. However, no difference between straight and averted was observed when only the presence of a face with open eyes had to be detected. Thus, the stare-in-the crowd effect is only observed when eye gaze is selected as part of the target and only when features of the face have to be discriminated. Our findings suggest that preference for straight gaze bears on target-related processes rather than on attentional capture per se.     

位置和内容对网页广告效果影响的眼动评估

使用TobiiT120型眼动仪,以16名大学生为被试,记录他们阅读嵌有网页广告新闻网页时的眼动注视过程,以探讨广告呈现位置、新闻内容与网页广告的相关性是否影响人们对网页广告的注视。实验采用3（广告位置：上方、中间、下方）×2（相关性：相关、不相关）两因素被试内设计。结果发现：（1）新闻内容和网页广告的相关性不影响人们对网页广告的加工;（2）对位于新闻上方和新闻中间的网页广告,被试的注视次数较多,且注视时间较长;（3）对位于新闻中间的网页广告,其再认效果优于位于新闻上方和新闻下方的广告。表明只有网页广告呈现位置这一因素影响被试对网页广告的注视。     

他人注视对不诚实行为的影响

有研究发现,他人的注视会使人们倾向于遵循社会规则,但甚少发现他人注视状态对不诚实行为的影响。该研究旨在通过比较眼睛的呈现类型和形式对不诚实行为的影响,来考察哪种注视状态能有效抑制个体的不诚实行为。结果发现,非伴随注视状态下,被试表现出不诚实行为,且不同类型的眼睛对被试的不诚实行为没有影响; 伴随注视状态下,直视眼抑制了被试的不诚实行为,而斜视眼则没有。这表明他人持续的注视可能作为内隐的名誉线索在一定程度上抑制了人们的不诚实行为。     

End in view: Joint end-state comfort depends on gaze and extraversion

This study investigated how humans adapt to a partner's movement in a joint pick-and-place task and examined the role of gaze behavior and personality traits in adapting to a partner. Two participants sitting side-by-side transported a cup from one end of a table to the other. The participant sitting on the left (the agent) moved the cup to an intermediate position from where the participant sitting on the right (the partner) transported it to a goal position with varying orientations. Hand, finger, cup movements and gaze behavior were recorded synchronously via motion tracking and portable eye tracking devices. Results showed interindividual differences in the extent of the agents' motor adaptation to the joint action goal, which were accompanied by differences in gaze patterns. The longer agents directed their gaze to a cue indicating the goal orientation, the more they adapted the rotation of the cup's handle when placing it at the intermediate position. Personality trait assessment showed that higher extraverted tendencies to strive for social potency went along with more adaptation to the joint goal. These results indicate that agents who consider their partner's end-state comfort use their gaze to gather more information about the joint action goal compared to agents who do not. Moreover, the disposition to enjoy leadership and make decisions in interpersonal situations seems to play a role in determining who adapts to a partner's task in joint action.     

Why does language interfere with vision-based tasks?

Conversation with a remote person can interfere with performing vision-based tasks. Two experiments tested the role of general executive resources and spatial attentional resources in this interference. Both experiments assessed performance in vision-based tasks as participants engaged in a language task involving a virtual remote speaker. In both experiments, the language task interfered with the vision task more when participants were speaking or planning what to say next than when they were listening. In Experiment 1, speaking or planning what to say next were also associated with higher interference from a visual distractor than listening, indicating that preparing to speak and speaking pose higher executive requirements than listening. In both experiments, localizing the voice of the remote speaker to the front of participants slightly reduced interference in comparison to other directions. This suggests that remote conversation requires spatial attention resources for representing the position of the remote person.