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Other's eye gaze is a powerful attention orienting cue that can change our perception of objects in the environment. Here, we seek to characterize the influence of attention orienting by eye gaze on the neural processing of visual targets. We used a Posner-like cueing paradigm to investigate with magnetoencephalography the brain responses associated with target processing. We analyzed the cerebral sources of the evoked responses to visual targets that were validly or invalidly cued by eye gaze. The effect of attention orienting was reflected in faster reaction times to valid than invalid targets. At the brain level, we showed an early influence of attention orienting by gaze with enhanced brain responses for invalid relative to valid targets. This influence was maximum contra-laterally to the target, with a right hemisphere dominance. Responses to targets presented in the left visual field were modulated between 91 and 400ms in the right posterior parietal and occipital cortices. Responses to targets presented in the right visual field were modulated between 174 and 218ms in the left superior parietal cortex. Our results confirm previous EEG studies that demonstrated early influence of attention orienting by gaze on target processing and provide evidence for the sources of this effect in occipito-parietal regions. This early influence may reflect the first stage of the perceptual changes induced by social attention., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Gaze direction is an important social signal for human beings. Beside the role of gaze in attention orienting, direct gaze (that is, gaze directed toward an observer) is a highly relevant biological stimulus that elicits attention capture and increases face encoding. Brain imaging studies have emphasized the role of the superior temporal sulcus (STS) in the coding of gaze direction and in the integration of gaze and head cues of social attention. The dynamics of the processing and integration of these cues remains, however, unclear. In order to address this question, we used deviated and frontal faces with averted and direct gaze in a combined electro- and magneto- encephalography (EEG-MEG) study. We showed distinct effects of gaze direction on the N170 and M170 responses. There was an interaction between gaze direction and head orientation between 134 and 162ms in MEG and a main effect of gaze direction between 171 and 186ms in EEG. These effects involved the posterior and anterior regions of the STS respectively. Both effects also emphasized the sensitivity to direct gaze. These data highlight the central role of the STS in gaze processing., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

It has recently been demonstrated that eye contact influences bodily self-awareness. Here, we investigated if the belief of being the target of another person's attention may also induce such influence. We created videos of an individual wearing two different pairs of sunglasses. We manipulated the participants to believe that they were in on-line connection with the individual and that one of the pairs of sunglasses was obstructed so that the individual could not see them through it. We demonstrated that the perception of an individual wearing see-through sunglasses, as compared to obstructed sunglasses or a low-level baseline condition, led to a greater correlation between the participants' rating of the intensity of their bodily reactions and their skin conductance response to emotional pictures. This shows that the belief to be watched by another social agent increases bodily self-awareness and further suggests that such belief is embedded in direct gaze perception., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Our preferences are sensitive to social influences. For instance, we like more the objects that are looked-at by others than non-looked-at objects. Here, we explored this liking effect, using a modified paradigm of attention cueing by gaze. First, we investigated if the liking effect induced by gaze relied on motoric representations of the target object by testing if the liking effect could be observed for non-manipulable (alphanumeric characters) as well as for manipulable items (common tools). We found a significant liking effect for the alphanumeric items. Second, we tested if another type of powerful social cue could also induce a liking effect. We used an equivalent paradigm but with pointing hands instead of gaze cues. Pointing hands elicited a robust attention-orienting effect, but they did not induce any significant liking effect. This study extends previous findings and reinforces the view of eye gaze as a special cue in human interactions.

To understand social interactions, we must decode dynamic social cues from seen faces. Here, we used magnetoencephalography (MEG) to study the neural responses underlying the perception of emotional expressions and gaze direction changes as depicted in an interaction between two agents. Subjects viewed displays of paired faces that first established a social scenario of gazing at each other (mutual attention) or gazing laterally together (deviated group attention) and then dynamically displayed either an angry or happy facial expression. The initial gaze change elicited a significantly larger M170 under the deviated than the mutual attention scenario. At around 400 ms after the dynamic emotion onset, responses at posterior MEG sensors differentiated between emotions, and between 1000 and 2200 ms, left posterior sensors were additionally modulated by social scenario. Moreover, activity on right anterior sensors showed both an early and prolonged interaction between emotion and social scenario. These results suggest that activity in right anterior sensors reflects an early integration of emotion and social attention, while posterior activity first differentiated between emotions only, supporting the view of a dual route for emotion processing. Altogether, our data demonstrate that both transient and sustained neurophysiological responses underlie social processing when observing interactions between others.

Diminished social attention is often considered to be a central deficit in autism spectrum disorders (ASDs). We further investigate this hypothesis by measuring the distracting power of social and non-social stimuli in the context of a Stroop task among children with ASD and typically developing controls (TDCs). Our results show that Stroop interference increases with social versus non-social distracters in TDCs, whereas the opposite pattern occurs in ASD. Within social stimuli, however, the superiority of direct gaze previously reported in the literature did not differ between the groups. Our data thus suggest that ASD children assign less weight to social than non-social stimuli, but that within social signals, salient stimuli remain prioritized.

Although the nature of the relationship between attention and awareness is actively debated, the possibility that different forms of attention might interact differently with awareness has never been directly tested. We examine here whether voluntary and involuntary spatial attentions, two forms of attention that were distinguished by manipulating the predictability of central arrow cues, interact in the same way with visual awareness. Conscious perception was enhanced by both voluntary and involuntary attentions, and to a similar extent, suggesting volition may not be an essential feature for awareness. However, the influence of attention was dependent on the awareness of the target stimulus: Voluntary attention shortened reaction times and improved discrimination accuracy of cued relative to uncued stimuli, but only when the stimuli were consciously perceived. Involuntary attention shortened reaction times for cued relative to uncued target stimuli, but only when the stimuli were not consciously perceived. Our results imply that the nature of the relationship between attention and awareness is not a simple one but depends on the type of attention involved. More specifically, our results suggest that the aware or unaware status of the stimulus could determine whether attentional facilitation is driven by voluntary or involuntary mechanisms, a proposal that goes in the opposite direction of the classical view that attention controls awareness. Because voluntary attentional benefits were observed in aware trials but involuntary attentional benefits were observed in unaware trials only, our results also argue against the idea that attentional effects on conscious and unconscious processing are fundamentally of the same nature., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

Eye contact is a highly salient and fundamentally social signal. This entails that the mere perception of direct gaze may trigger differentiated neurobehavioral responses as compared to other gaze directions. We investigated this issue using a visual word-spelling task where faces under different gaze directions and head orientations were displayed on-screen concomitantly with the words. We show evidence for automatic increase of skin conductance response (SCR), indicative of arousal, associated with the perception of direct gaze as compared to both averted gaze and closed eyes. Moreover, the perception of averted gaze was associated with an increase of electromyographic (EMG) corrugator activity. These effects were observed in two demanding word-spelling tasks, but not in a simple letter decision task. We propose to interpret these findings in terms of the social value of direct and averted gaze and conclude that some circumstances such as the task at hand may be essential for uncovering the neurobehavioral responses associated with the perception of others' gaze.

Direct gaze or eye contact is a strong social signal, which triggers distinct processes as compared to other gaze directions. Thus, direct gaze could be early dissociated from averted gaze during the processing of gaze direction. In order to examine the processing of gaze contact relative to averted gaze, we studied evoked potentials in human adults in response to the apparent motion of gaze. Deviated and frontal faces were presented with a fixed gaze direction, followed by an apparent movement of the eyes either toward the subject or away from him/her. The results showed that the perception of direct relative to averted gaze evoked a greater, later and longer lasting N170, suggesting that gaze contact recruited more resources than averted gaze in the early stage of gaze direction processing. Furthermore, direct and averted motion of gaze elicited distinct ERP components between 160 and 210 ms, initiated over centro-parietal electrodes. Source reconstruction revealed the involvement of the Theory-of-Mind network, including the regions of the superior temporal sulcus, the medial prefrontal and the orbitofrontal cortices, in this early dissociation. In addition, the perception of gaze contact relative to averted gaze yielded increased fronto-central P3a and parieto-occipital P3b. All the results were significant whatever the head orientation. Our findings show that gaze contact, as compared to other gaze directions, is an essential social cue which recruits early specific processes. The dissociation between direct and averted gaze processing occurs as soon as 160 ms, involving the social brain network.

Eye contact is a crucial social cue constituting a frequent preliminary to interaction. Thus, the perception of others' gaze may be associated with specific processes beginning with asymmetries in the detection of direct versus averted gaze. We tested this hypothesis in two behavioural experiments using realistic eye stimuli in a visual search task. We manipulated the head orientation (frontal or deviated) and the visual field (right or left) in which the target appeared at display onset. We found that direct gaze targets presented among averted gaze distractors were detected faster and better than averted gaze targets among direct gaze distractors, but only when the head was deviated. Moreover, direct gaze targets were detected very quickly and efficiently regardless of head orientation and visual field, whereas the detection of averted gaze was strongly modulated by these factors. These results suggest that gaze contact has precedence over contextual information such as head orientation and visual field.

Gaze is one of the most important cues for human communication and social interaction. In particular, gaze contact is the most primary form of social contact and it is thought to capture attention. A very early-differentiated brain response to direct versus averted gaze has been hypothesized. Here, we used high-density electroencephalography to test this hypothesis. Topographical analysis allowed us to uncover a very early topographic modulation (40–80 ms) of event-related responses to faces with direct as compared to averted gaze. This modulation was obtained only in the condition where intact broadband faces–as opposed to high-pass or low-pas filtered faces–were presented. Source estimation indicated that this early modulation involved the posterior parietal region, encompassing the left precuneus and inferior parietal lobule. This supports the idea that it reflected an early orienting response to direct versus averted gaze. Accordingly, in a follow-up behavioural experiment, we found faster response times to the direct gaze than to the averted gaze broadband faces. In addition, classical evoked potential analysis showed that the N170 peak amplitude was larger for averted gaze than for direct gaze. Taken together, these results suggest that direct gaze may be detected at a very early processing stage, involving a parallel route to the ventral occipito-temporal route of face perceptual analysis. [ABSTRACT FROM AUTHOR]

Highlights: [•] We examined if trait anxiety may affect early stages of emotional face processing. [•] We tested emotional modulation of the P1, N170 and EPN using happy and fearful vs. neutral faces. [•] The occipital P1 was greater for happy vs. neutral faces, only in high anxious subjects. [•] The N170 and EPN were modulated by fearful vs. neutral faces in high and low trait anxious subjects. [•] Our results underline an early bias towards positive stimuli in trait anxiety. [ABSTRACT FROM AUTHOR]

Others' gaze and emotional facial expression are important cues for the process of attention orienting. Here, we investigated with magnetoencephalography (MEG) whether the combination of averted gaze and fearful expression may elicit a selectively early effect of attention orienting on the brain responses to targets. We used the direction of gaze of centrally presented fearful and happy faces as the spatial attention orienting cue in a Posner-like paradigm where the subjects had to detect a target checkerboard presented at gazed-at (valid trials) or non gazed-at (invalid trials) locations of the screen. We showed that the combination of averted gaze and fearful expression resulted in a very early attention orienting effect in the form of additional parietal activity between 55 and 70 ms for the valid versus invalid targets following fearful gaze cues. No such effect was obtained for the targets following happy gaze cues. This early cue-target validity effect selective of fearful gaze cues involved the left superior parietal region and the left lateral middle occipital region. These findings provide the first evidence for an effect of attention orienting induced by fearful gaze in the time range of C1. In doing so, they demonstrate the selective impact of combined gaze and fearful expression cues in the process of attention orienting. [ABSTRACT FROM AUTHOR]