Visuospatial attention shifts by gaze and arrow cues: An ERP study

The emotion of sound target modulates the auditory gaze cueing effect

The auditory gaze cueing effect (auditory-GCE) is a faster response to auditory targets at an eye-gaze cue location than at a non-cue location. Previous research has found that auditory-GCE can be influenced by the integration of both gaze direction and emotion conveyed through facial expressions. However, it is unclear whether the emotional information of auditory targets can be cross-modally integrated with gaze direction to affect auditory-GCE. Here, we set neutral faces with different gaze directions as cues and three emotional sounds (fearful, happy, and neutral) as targets to investigate how the emotion of sound target modulates the auditory-GCE. Moreover, we conducted a controlled experiment using arrow cues. The results show that the emotional content of sound targets influences the auditory-GCE but only for those induced by facial cues. Specifically, fearful sounds elicit a significantly larger auditory-GCE compared to happy and neutral sounds, indicating that the emotional content of auditory targets plays a modulating role in the auditory-GCE. Furthermore, this modulation appears to occur only at a higher level of social meaning, involving the integration of emotional information from a sound with social gaze direction, rather than at a lower level, which involves the integration of direction and auditory emotion.

Segregation of Neural Circuits Involved in Social Gaze and Non-Social Arrow Cues: Evidence from an Activation Likelihood Estimation Meta-Analysis

Orienting attention by social gaze cues shares some characteristics with orienting attention by non-social arrow cues, but it is unclear whether they rely on similar neural mechanisms. The present ALE-meta-analysis assessed the pattern of brain activation reported in 40 single experiments (18 with arrows, 22 with gaze), with a total number of 806 participants. Our findings show that the network for orienting attention by social gaze and by non-social arrow cues is in part functionally segregated. Orienting by both types of cues relies on the activity of brain regions involved in endogenous attention (the superior frontal gyrus). Importantly, only orienting by gaze cues was also associated with the activity of brain regions involved in exogenous attention (medial frontal gyrus), processing gaze, and mental state attribution (superior temporal sulcus, temporoparietal junction).

Uncovering the cognitive mechanisms underlying the gaze cueing effect

The gaze cueing effect is the tendency for people to respond faster to targets appearing at locations gazed at by others, compared with locations gazed away from by others. The effect is robust, widely studied, and is an influential finding within social cognition. Formal evidence accumulation models provide the dominant theoretical account of the cognitive processes underlying speeded decision-making, but they have rarely been applied to social cognition research. In this study, using a combination of individual-level and hierarchical computational modelling techniques, we applied evidence accumulation models to gaze cueing data (three data sets total, N = 171, 139,001 trials) for the first time to assess the relative capacity that an attentional orienting mechanism and information processing mechanisms have for explaining the gaze cueing effect. We found that most participants were best described by the attentional orienting mechanism, such that response times were slower at gazed away from locations because they had to reorient to the target before they could process the cue. However, we found evidence for individual differences, whereby the models suggested that some gaze cueing effects were driven by a short allocation of information processing resources to the gazed at location, allowing for a brief period where orienting and processing could occur in parallel. There was exceptionally little evidence to suggest any sustained reallocation of information processing resources neither at the group nor individual level. We discuss how this individual variability might represent credible individual differences in the cognitive mechanisms that subserve behaviourally observed gaze cueing effects.

Temperament and probabilistic predictive coding in visual-spatial attention

Cholinergic (Ach), Noradrenergic (NE), and Dopaminergic (DA) pathways play an important role in the regulation of spatial attention. The same neurotransmitters are also responsible for inter-individual differences in temperamental traits. Here we explored whether biologically defined temperamental traits determine differences in the ability to orient spatial attention as a function of the probabilistic association between cues and targets. To this aim, we administered the Structure of Temperament Questionnaire (STQ-77) to a sample of 151 participants who also performed a Posner task with central endogenous predictive (80 % valid/20 % invalid) or non-predictive cues (50 % valid/50 % invalid). We found that only participants with high scores in Plasticity and Intellectual Endurance showed a selective abatement of attentional costs with non-predictive cues. In addition, stepwise regression showed that costs in the non-predictive condition were negatively predicted by scores in Plasticity and positively predicted by scores in Probabilistic Thinking. These results show that stable temperamental characteristics play an important role in defining the inter-individual differences in attentional behaviour, especially in the presence of different probabilistic organisations of the sensory environment. These findings emphasize the importance of considering temperamental and personality traits in social and professional environments where the ability to control one's attention is a crucial functional skill.

Impaired orienting function detected through eye movements in patients with temporal lobe epilepsy

Objective

Patients with temporal lobe epilepsy (TLE) often exhibit attention function impairment. The orienting network is the subsystem of the attention network that has not been fully studied. In this study, we used eye-tracking technology with an attention network test (ANT)-based task to assess the orienting function of TLE patients, aiming to characterize their eye movement patterns.

Methods

A total of 37 TLE patients and 29 healthy controls (HCs) completed the ANT task based on eye-tracking technology. Orienting function damage was mainly assessed by the ANT orienting effect. Eye movement metrics, such as mean first goal-directed saccade latency (MGSL), total saccades, and saccade amplitudes, were compared between groups.

Results

The TLE patients had a significantly lower ANT orienting effect (HC, 54.05 ± 34.05; TLE, 32.29 ± 39.54) and lower eye-tracking orienting effect (HC, 116.98 ± 56.59; TLE, 86.72 ± 59.10) than those of the HCs. The larger orienting effects indicate that orienting responses are faster when receiving a spatial cue compared with a center cue. In the spatial cue condition, compared with HCs, the TLE group showed a longer first goal-directed saccade latency (HC, 76.77 ± 58.87 ms; TLE, 115.14 ± 59.15 ms), more total saccades (HC, 28.46 ± 12.30; TLE, 36.69 ± 15.13), and larger saccade amplitudes (HC, 0.75° ± 0.60°; TLE, 1.36° ± 0.89°). Furthermore, there was a positive correlation of the orienting-effect score between the ANT task and eye-tracking metrics (r = 0.58, p < 0.05).

Conclusion

We innovatively developed a new detection method using eye-tracking technology in combination with an ANT-based task to detect the orienting function in TLE patients. The current research demonstrated that TLE patients had a significant orienting dysfunction with a specific saccade pattern characterized by a longer first goal-directed saccade latency, more total saccades, and larger saccade amplitudes. These oculomotor metrics are likely to be a better indicator of orienting function and may potentially be used for behavioral-based interventions and long-term cognition monitoring in TLE patients.

Alpha oscillations encode Bayesian belief updating underlying attentional allocation in dynamic environments

In a dynamic environment, expectations of the future constantly change based on updated evidence and affect the dynamic allocation of attention. To further investigate the neural mechanisms underlying attentional expectancies, we employed a modified Central Cue Posner Paradigm in which the probability of cues being valid (that is, accurately indicated the upcoming target location) was manipulated. Attentional deployment to the cued location (α), which was governed by precision of predictions on previous trials, was estimated using a hierarchical Bayesian model and was included as a regressor in the analyses of electrophysiological (EEG) data. Our results revealed that before the target appeared, alpha oscillations (8∼13 Hz) for high-predictability cues (88 % valid) were significantly predicted by precision-dependent attention (α). This relationship was not observed under low-predictability conditions (69 % and 50 % valid cues). After the target appeared, precision-dependent attention (α) correlated with alpha band oscillations only in the valid cue condition and not in the invalid condition. Further analysis under conditions of significant attentional modulation by precision suggested a separate effect of cue orientation. These results provide new insights on how trial-by-trial Bayesian belief updating relates to alpha band encoding of environmentally-sensitive allocation of visual spatial attention.

Selection within working memory impairs perceptual detection

There is broad consensus supporting the reciprocal influence of working memory (WM) and attention. Top-down mechanisms operate to cope with either environmental or internal demands. In that sense, it is possible to select an item within the contents of WM to endow it with prioritized access. Although evidence supports that maintaining an item in this privileged state does not rely on sustained visual attention, it is unknown whether selection within WM depends on perceptual attention. To answer this question, we recorded electrophysiological neural activity while participants performed a retro-cue task in which we inserted a detection task in the delay period after retro-cue presentation. Critically, the onset of to-be-detected near threshold stimuli was unpredictable, and thus, sustained perceptual spatial attention was needed to accomplish the detection task from the offset of the retro-cue. At a behavioral level, we found decreased visual detection when a WM representation was retro-cued. At a neural level, alpha oscillatory activity confirmed a spatial shift of attention to the retro-cued representation. We interpret the convergence of neural oscillations and behavioral data to point towards the theory that selection within WM could be accomplished through a perceptual attentional mechanism.

When a look is enough: Neurophysiological correlates of referential speaker gaze in situated comprehension

Behavioral studies have shown that speaker gaze to objects in a co-present scene can influence listeners' expectations about how the utterance will unfold. These findings have recently been supported by ERP studies that linked the underlying mechanisms of the integration of speaker gaze with an utterance meaning representation to multiple ERP components. This leads to the question, however, as to whether speaker gaze should be considered part of the communicative signal itself, such that the referential information conveyed by gaze can help listeners not only form expectations but also to confirm referential expectations induced by the prior linguistic context. In the current study, we investigated this question by conducting an ERP experiment (N=24, Age:[19,31]), in which referential expectations were established by linguistic context together with several depicted objects in the scene. Those expectations then could be confirmed by subsequent speaker gaze that preceded the referential expression. Participants were presented with a centrally positioned face performing gaze actions aligned to utterances comparing two out of three displayed objects, with the task to judge whether the sentence was true given the provided scene. We manipulated the gaze cue to be either Present (toward the subsequently named object) or Absent preceding contextually Expected or Unexpected referring nouns. The results provided strong evidence for gaze as being treated as an integral part of the communicative signal: While in the absence of gaze, effects of phonological verification (PMN), word meaning retrieval (N400) and sentence meaning integration/evaluation (P600) were found on the unexpected noun, in the presence of gaze effects of retrieval (N400) and integration/evaluation (P300) were solely found in response to the pre-referent gaze cue when it was directed toward the unexpected referent with attenuated effects on the following referring noun.

The Effects of Directional and Non-Directional Stimuli during a Visuomotor Task and Their Correlation with Reaction Time: An ERP Study

Different visual stimuli can capture and shift attention into different directions. Few studies have explored differences in brain response due to directional (DS) and non-directional visual stimuli (nDS). To explore the latter, event-related potentials (ERP) and contingent negative variation (CNV) during a visuomotor task were evaluated in 19 adults. To examine the relation between task performance and ERPs, the participants were divided into faster (F) and slower (S) groups based on their reaction times (RTs). Moreover, to reveal ERP modulation within the same subject, each recording from the single participants was subdivided into F and S trials based on the specific RT. ERP latencies were analysed between conditions ((DS, nDS); (F, S subjects); (F, S trials)). Correlation was analysed between CNV and RTs. Our results reveal that the ERPs' late components are modulated differently by DS and nDS conditions in terms of amplitude and location. Differences in ERP amplitude, location and latency, were also found according to subjects' performance, i.e., between F and S subjects and trials. In addition, results show that the CNV slope is modulated by the directionality of the stimulus and contributes to motor performance. A better understanding of brain dynamics through ERPs could be useful to explain brain states in healthy subjects and to support diagnoses and personalized rehabilitation in patients with neurological diseases.

Time-frequency analysis of brain activity in response to directional and non-directional visual stimuli: an event related spectral perturbations (ERSP) study

Objective.A large part of the cerebral cortex is dedicated to the processing of visual stimuli and there is still much to understand about such processing modalities and hierarchies. The main aim of the present study is to investigate the differences between directional visual stimuli (DS) and non-directional visual stimuli (n-DS) processing by time-frequency analysis of brain electroencephalographic activity during a visuo-motor task. Electroencephalography (EEG) data were divided into four regions of interest (ROIs) (frontal, central, parietal, occipital).Approach.The analysis of the visual stimuli processing was based on the combination of electroencephalographic recordings and time-frequency analysis. Event related spectral perturbations (ERSPs) were computed with spectrum analysis that allow to obtain the average time course of relative changes induced by the stimulus presentation in spontaneous EEG amplitude spectrum.Main results.Visual stimuli processing enhanced the same pattern of spectral modulation in all investigated ROIs with differences in amplitudes and timing. Additionally, statistically significant differences in occipital ROI between the DS and n-DS visual stimuli processing in theta, alpha and beta bands were found.Significance.These evidences suggest that ERSPs could be a useful tool to investigate the encoding of visual information in different brain regions. Because of their simplicity and their capability in the representation of brain activity, the ERSPs might be used as biomarkers of functional recovery for example in the rehabilitation of visual dysfunction and motor impairment following a stroke, as well as diagnostic tool of anomalies in brain functions in neurological diseases tailored to personalized treatments in clinical environment.

Does Eye Gaze Uniquely Trigger Spatial Orienting to Socially Relevant Information? A Behavioral and ERP Study

Using behavioral and event-related potential (ERP) measures, the present study examined whether eye gaze triggers a unique form of attentional orienting toward threat-relevant targets. A threatening or neutral target was presented after a non-predictive gaze or an arrow cue. In Experiment 1, reaction times indicated that eye gaze and arrow cues triggered different attention orienting towards threatening targets, which was confirmed by target-elicited P3b latency in Experiment 2. Specifically, for targets preceded by arrow and gaze cues, P3b peak latency was shorter for neutral targets than threatening targets. However, the latency differences were significantly smaller for gaze cues than for arrow cues. Moreover, target-elicited N2 amplitude indicated a significantly stronger cue validity effect of eye gaze than that of arrows. These findings suggest that eye gaze uniquely triggers spatial attention orienting to socially threatening information.

Motion or sociality? The cueing effect and temporal course of autistic traits on gaze-triggered attention

Gaze-triggered attention changes have been found in individuals with high autistic traits in the nonclinical population. However, gaze cues used in previous studies imply not only sociality of gaze but also the motion of gaze. To exclude the influence of motion, we manipulated the cue sociality by setting dot cues with similar motion characteristics as gaze cues to explore the underlying reasons of gaze-triggered attention changes in individuals with high autistic traits. We used a cueing paradigm within a visual matching task and recorded individuals' eye movements. Both the RT and eye movement of probe interface showed the benefit from gaze of the low autistic trait group was larger than that from dot and was larger than that of the high autistic trait group. While the high autistic trait group show similar benefit between gaze and dot. Eye movement results showed the dynamic changes of validity effect in two groups. The interaction between autistic traits and cue sociality was not significant within the 500 ms of cue presentation, marginally significant within 500-1,000 ms after cue presentation, but significant after 1,000 ms of cue presentation. The results demonstrated that the changes of gaze-triggered attention in individuals with high autistic traits was mainly caused by the sociality of gaze in the relative late stage.

Investigating facilitatory versus inhibitory effects of dynamic social and non-social cues on attention in a realistic space

This study aimed to investigate the facilitatory versus inhibitory effects of dynamic non-predictive central cues presented in a realistic environment. Realistic human-avatars initiated eye contact and then dynamically looked to the left, right or centre of a table. A moving stick served as a non-social control cue and participants localised (Experiment 1) or discriminated (Experiment 2) a contextually relevant target (teapot/teacup). The cues movement took 500 ms and stimulus onset asynchronies (SOA, 150 ms/300 ms/500 ms/1000 ms) were measured from movement initiation. Similar cuing effects were seen for the social avatar and non-social stick cue across tasks. Results showed facilitatory processes without inhibition, though there was some variation by SOA and task. This is the first time facilitatory versus inhibitory processes have been directly investigated where eye contact is initiated prior to gaze shift. These dynamic stimuli allow a better understanding of how attention might be cued in more realistic environments.

Altered social cognition in a community sample of women with disordered eating behaviours: a multi-method approach

Prior work suggests that individuals with an eating disorder demonstrate task-based and overall differences in sociocognitive functioning. However, the majority of studies assessed specifically anorexia nervosa and often employed a single experimental paradigm, providing a piecemeal understanding of the applicability of various lab tasks in denoting meaningful differences across diverse individuals. The current study was designed to address these outstanding issues. Participants were undergraduate females who self-identified as having an official (n = 18) eating disorder diagnosis or disordered eating behaviours with no diagnosis (n = 18), along with a control group (n = 32). Participants completed three social tasks of increasing complexity with different outcome measures, namely a gaze cueing task, passive video-watching using eyetracking, and a task to measure preferred social distance. Results diverged as a function of group across tasks; only the control group produced typical social attention effects, the disordered eating group looked significantly more at faces, and the eating disorder group demonstrated a significantly larger preferred social distance. These results suggest variations in task efficacy and demonstrate that altered sociocognitive functioning extends beyond official eating disorder diagnosis.

From Gaze Perception to Social Cognition: The Shared-Attention System

When two people look at the same object in the environment and are aware of each other's attentional state, they find themselves in a shared-attention episode. This can occur through intentional or incidental signaling and, in either case, causes an exchange of information between the two parties about the environment and each other's mental states. In this article, we give an overview of what is known about the building blocks of shared attention (gaze perception and joint attention) and focus on bringing to bear new findings on the initiation of shared attention that complement knowledge about gaze following and incorporate new insights from research into the sense of agency. We also present a neurocognitive model, incorporating first-, second-, and third-order social cognitive processes (the shared-attention system, or SAS), building on previous models and approaches. The SAS model aims to encompass perceptual, cognitive, and affective processes that contribute to and follow on from the establishment of shared attention. These processes include fundamental components of social cognition such as reward, affective evaluation, agency, empathy, and theory of mind.

The N170 event-related potential differentiates congruent and incongruent gaze responses in gaze leading

To facilitate social interactions, humans need to process the responses that other people make to their actions, including eye movements that could establish joint attention. Here, we investigated the neurophysiological correlates of the processing of observed gaze responses following the participants’ own eye movement. These observed gaze responses could either establish, or fail to establish, joint attention. We implemented a gaze leading paradigm in which participants made a saccade from an on-screen face to an object, followed by the on-screen face either making a congruent or incongruent gaze shift. An N170 event-related potential was elicited by the peripherally located gaze shift stimulus. Critically, the N170 was greater for joint attention than non-joint gaze both when task-irrelevant (Experiment 1) and task-relevant (Experiment 2). These data suggest for the first time that the neurocognitive system responsible for structural encoding of face stimuli is affected by the establishment of participant-initiated joint attention.

Deconstructing Reorienting of Attention: Cue Predictiveness Modulates the Inhibition of the No-target Side and the Hemispheric Distribution of the P1 Response to Invalid Targets

Orienting of attention produces a “sensory gain” in the processing of visual targets at attended locations and an increase in the amplitude of target-related P1 and N1 ERPs. P1 marks gain reduction at unattended locations; N1 marks gain enhancement at attended ones. Lateral targets that are preceded by valid cues also evoke a larger P1 over the hemisphere contralateral to the no-target side, which reflects inhibition of this side of space [Slagter, H. A., Prinssen, S., Reteig, L. C., & Mazaheri, A. Facilitation and inhibition in attention: Functional dissociation of pre-stimulus alpha activity, P1, and N1 components. Neuroimage, 125, 25–35, 2016]. To clarify the relationships among cue predictiveness, sensory gain, and the inhibitory P1 response, we compared cue- and target-related ERPs among valid, neutral, and invalid trials with predictive (80% valid/20% invalid) or nonpredictive (50% valid/50% invalid) directional cues. Preparatory facilitation over the visual cortex contralateral to the cued side of space (lateral directing attention positivity component) was reduced during nonpredictive cueing. With predictive cues, the target-related inhibitory P1 was larger over the hemisphere contralateral to the no-target side not only in response to valid but also in response to neutral and invalid targets: This result highlights a default inhibitory hemispheric asymmetry that is independent from cued orienting of attention. With nonpredictive cues, valid targets reduced the amplitude of the inhibitory P1 over the hemisphere contralateral to the no-target side whereas invalid targets enhanced the amplitude of the same inhibitory component. Enhanced inhibition was matched with speeded reorienting to invalid targets and drop in attentional costs. These findings show that reorienting of attention is modulated by the combination of cue-related facilitatory and target-related inhibitory activity.

Can irrelevant but salient visual cues compensate for the age-related decline in cognitive conflict resolution?-An ERP study

We studied a Posner-type gaze-cued version of a Simon task to characterize age-related changes in visuospatial attention and inhibitory control. Earlier results had indicated that the direction of gaze is a strong social cue that speeds response times; so we wondered whether, as a task-irrelevant stimulus, it could compensate for age-related impairment of inhibitory processes in the elderly. Our results assessed the Simon effect by: reaction time, error rate, the P3 component and the lateralized readiness potential (LRP). We found that the Simon effect was larger in the older group confirming an increased sensitivity to interference and also suggesting a decreased inhibitory control in older adults. LRP results showed that aging and stimulus-response incongruency delayed the selection of the responses–indexed by longer s-LRP latency data–, and also decreased the efficiency of motor inhibition in the Simon task–the s-LRP amplitude of both wrong- and correct-side activation was larger in older adults, and the latency difference of these two components was longer in this age-group. Also a larger N2pc amplitude in the congruent, compared to incongruent gaze condition, showed an increased visuospatial attention when the gaze-cueing drew attention to the target stimulus. This gaze-cueing could not be ignored and hence it modified task processing in the older age group, which was evident in the incongruent Simon condition where the congruent gaze increased older adults’ reaction time and their error rate; but there was no difference observed in the congruent Simon condition. Since the anticipated facilitation of reaction times did not occur, we suggest that general slowing and decreased inhibitory functions in the elderly caused the social cue not to be a supporting stimulus but rather to be a further burden on their cognitive processing.

The influence of joint attention and partner trustworthiness on cross-modal sensory cueing

Joint attention refers to the coordinated attention between social partners to an object of shared interest, usually involving shared gaze toward the object. In the laboratory, however, joint attention is often investigated using computerized gaze cueing tasks that do not allow shared gaze. Instead, these computerized tasks require the participant to maintain fixation on the virtual partner's face, while the partner gazes to the left or right. Here we designed a modified gaze cueing task that better simulates a natural joint attention episode by allowing shared gaze, while still maintaining tight experimental control. In our computerized task the participant's gaze and the gaze of a virtual partner were manipulated independently, resulting in shared or unshared gaze. Following each gaze shift of the virtual partner a touch stimulus was delivered on one of the cheeks of the participant. We analyzed behavioral and neural (electro-encephalography) responses to the touch. Faster reaction-times and stronger lateralization of alpha power were observed when the touched cheek was in a jointly attended hemispace compared with a singly attended or unattended hemispace. Importantly, these effects were unique to joint attention and could not be explained as the additive effects of own gaze and gaze cue direction. Underlining its social nature, we found that the behavioral effect was absent when we repeated our experiment with nonsocial cues (arrows) instead of gaze cues. Furthermore, when we compared trustworthy with untrustworthy virtual partners (trustworthiness judgements based on facial appearance) we found the effect only for trustworthy and not for untrustworthy virtual partners. We conclude that joint attention based on shared gaze influences attentional orienting such that cross-modal sensory processing at the jointly attended location is facilitated, particularly when the partner is trustworthy. This indicates that social interactions and trustworthiness judgements affect cortical and behavioral responses to sensory information.

Are eyes special? Electrophysiological and behavioural evidence for a dissociation between eye-gaze and arrows attentional mechanisms

It has been proposed that attention triggered by eye-gaze may represent a unique attentional process, different from that triggered by non-social stimuli such as arrows. To investigate this issue, in the present study we compared the temporal dynamics of the conflict processing triggered by eye-gaze and arrow stimuli. We investigated the electrophysiological activity during a task in which participants were required to identify the direction of laterally presented eye-gaze or arrow targets. Opposite behavioural effects were observed: while arrows produced the typical effect, with faster responses when they were congruent with their position, eye-gaze targets produced a reversed effect with faster responses when they were incongruent. Event-related potentials showed common and dissociable congruency modulation: whereas eye-gaze and arrows showed similar effects on earlier ERP components (P1 and N1), they led to opposite effects in later components such as N2 and P3. This represents the first electrophysiological demonstration of both early shared and later dissociable congruency effects for eye-gaze and arrow stimuli.

Large lateralized EDAN-like brain potentials in a gaze-shift detection task

Attentional cueing tasks using gaze direction as spatial cues have sometimes yielded an early directing attention negativity (EDAN) component in the ERP, presumably reflecting the initial orienting toward the cued location. However, other studies have failed to identify an EDAN component for gaze cues, yielding an inconsistent picture. In the present study, we re-examined the EDAN to gaze cueing, using a continuous task where the specific direction of the gaze changes was task irrelevant. Face stimuli changed gaze direction several times during each trial between direct, left-, and right-averted positions. Participants counted the number of gaze shifts during the trial. Results showed an unusually large EDAN-like ERP asymmetry at posterior scalp sites that was of similar amplitude for large and small gaze shifts into the periphery. Shifts from an averted position toward a direct gaze elicited a qualitatively similar but smaller effect than shifts into the periphery. Together, these findings shed new light on gaze-elicited spatial attention as they indicate a reflexive attention orienting, following the direction of gaze motion, even when the gaze direction itself is irrelevant for the task.

The role of the motion cue in the dynamic gaze-cueing effect: A study of the lateralized ERPs

When face was inverted, dynamic gaze cues could still effectively direct attention despite the disruption of configural face processing, but the static gaze cues could not. The present study investigated the role of the motion cue in the dynamic Gaze-Cueing Effect (GCE). With schematic and real faces, we employed the gaze-cueing paradigm to examine the differences among three kinds of cues (static gaze cue, dynamic gaze cue and motion cue) based on behavioral results and event-related potentials. Behavioral results revealed significant GCE in all conditions. In the schematic face group, the motion cue (two symmetrical dots shifting slightly to the side) induced a significantly smaller GCE than the dynamic gaze cues (two symmetrical dots moving within a rounded circle), while in the real face group, the motion cue (that is, the inverted-face gaze cue) remained a strong GCE compared with other conditions. With regard to the ERP results, we found the early directing attention negativity (EDAN), which was sensitive to voluntary cues (e.g. arrow cue) rather than gaze cue, in the schematic motion cue condition, but not in the inverted-face gaze cue condition. We supposed that the motion cue (real face) could activate the configural face processing even when the face is inverted. This finding supported that EDAN reflected a cue-triggered attention shift.

FEF Excitability in Attentional Bias: A TMS-EEG Study

The role of distinct cortical regions in guiding social orienting needs further investigation. Our aim was to explore the contribution of the frontal eye field (FEF) in early orienting of attention towards stimuli with social value. We used a TMS-EEG approach to investigate event related potentials (ERPs; no-TMS block) and TMS evoked potentials (TEPs; TMS block) during the cueing phase of a modified version of the dot-probe task, comparing competing (face vs. house) and not competing (house vs. house) conditions. Our results revealed an increased amplitude of ERP components in the competing condition, showing greater posterior N170 and fronto-central vertex positive potential (VPP) and an enhanced frontal negative component at 250-270 ms from cue onset. TMS pulses over the FEF induced similar N170 and VPP amplified components. In addition, in the ERPs, a reduced positivity at 400 ms was shown when the face appeared on the left side vs. the right side of space. In contrast, in the TMS blocks, we found lateralized effects on N170 depending on the side of face presentation. The enhanced cortical excitability induced by TMS over the right FEF significantly correlated with the performance on the behavioral task, suggesting a link between the FEF activity during the cueing phase of the dot-probe task and the subsequent behavioral response times to the targets.

Gaze-cueing and endogenous attention operate in parallel

The present research assessed the nature of endogenous shifts of attention based on internally generated expectations (i.e., target location probability) and involuntary attention shifts following eye-gaze cues from line-drawings of schematic faces (Experiment 1) and photographs of real neutral faces (Experiment 2) and fearful faces (Experiment 3). The time-course of these two forms of attention was explored by manipulating the gaze-target SOA (i.e., 100 ms, 200 ms, 300 ms). In all three experiments, target location probability influenced responding at each SOA with faster responses to high probability than low probability targets. However, the time-course of involuntary attention shifts was dependent on the gaze-cueing stimulus employed. For photographs of neutral gaze, endogenous orienting of attention was most efficient at the briefest SOA with involuntary attention shifts emerging later. However, both schematic and fearful gaze-cues influenced responding across all SOAs, which is indicative of stronger gaze-cueing effects from these cues. At 200 ms there was an additive effect as responses were slowest when the target had been invalidly cued by neutral gaze and also appeared in the low probability location. Taken together these findings suggest that these forms of involuntary and endogenous attention can operate in parallel and relatively independently, but can show potentially differing levels of influence, dependent on the time course in which they take to operate.

Visual attention and action: How cueing, direct mapping, and social interactions drive orienting

Despite considerable interest in both action perception and social attention over the last 2 decades, there has been surprisingly little investigation concerning how the manual actions of other humans orient visual attention. The present review draws together studies that have measured the orienting of attention, following observation of another's goal-directed action. Our review proposes that, in line with the literature on eye gaze, action is a particularly strong orienting cue for the visual system. However, we additionally suggest that action may orient visual attention using mechanisms, which gaze direction does not (i.e., neural direct mapping and corepresentation). Finally, we review the implications of these gaze-independent mechanisms for the study of attention to action. We suggest that our understanding of attention to action may benefit from being studied in the context of joint action paradigms, where the role of higher level action goals and social factors can be investigated.

Brief Mindfulness Meditation Improves Attention in Novices: Evidence From ERPs and Moderation by Neuroticism

Past research has found that mindfulness meditation training improves executive attention. Event-related potentials (ERPs) have indicated that this effect could be driven by more efficient allocation of resources on demanding attentional tasks, such as the Flanker Task and the Attention Network Test (ANT). However, it is not clear whether these changes depend on long-term practice. In two studies, we sought to investigate the effects of a brief, 10-min meditation session on attention in novice meditators, compared to a control activity. We also tested moderation by individual differences in neuroticism and the possible underlying neural mechanisms driving these effects, using ERPs. In Study 1, participants randomly assigned to listen to a 10-min meditation tape had better accuracy on incongruent trials on a Flanker task, with no detriment in reaction times (RTs), indicating better allocation of resources. In Study 2, those assigned to listen to a meditation tape performed an ANT more quickly than control participants, with no detriment in performance. Neuroticism moderated both of these effects, and ERPs showed that those individuals lower in neuroticism who meditated for 10 min exhibited a larger N2 to incongruent trials compared to those who listened to a control tape; whereas those individuals higher in neuroticism did not. Together, our results support the hypothesis that even brief meditation improves allocation of attentional resources in some novices.

Spatiotemporal commonalities of fronto-parietal activation in attentional orienting triggered by supraliminal and subliminal gaze cues: An event-related potential study

Eye gaze triggers attentional shifts with and without conscious awareness. It remains unclear whether the spatiotemporal patterns of electric neural activity are the same for conscious and unconscious attentional shifts. Thus, the present study recorded event-related potentials (ERPs) and evaluated the neural activation involved in attentional orienting induced by subliminal and supraliminal gaze cues. Nonpredictive gaze cues were presented in the central field of vision, and participants were asked to detect a subsequent peripheral target. The mean reaction time was shorter for congruent gaze cues than for incongruent gaze cues under both presentation conditions, indicating that both types of cues reliably trigger attentional orienting. The ERP analysis revealed that averted versus straight gaze induced greater negative deflection in the bilateral fronto-central and temporal regions between 278 and 344 ms under both supraliminal and subliminal presentation conditions. Supraliminal cues, irrespective of gaze direction, induced a greater negative amplitude than did subliminal cues at the right posterior cortices at a peak of approximately 170 ms and in the 200-300 ms. These results suggest that similar spatial and temporal fronto-parietal activity is involved in attentional orienting triggered by both supraliminal and subliminal gaze cues, although inputs from different visual processing routes (cortical and subcortical regions) may trigger activity in the attentional network.

The Effect of Eye Contact Is Contingent on Visual Awareness

The present study explored how eye contact at different levels of visual awareness influences gaze-induced joint attention. We adopted a spatial-cueing paradigm, in which an averted gaze was used as an uninformative central cue for a joint-attention task. Prior to the onset of the averted-gaze cue, either supraliminal (Experiment 1) or subliminal (Experiment 2) eye contact was presented. The results revealed a larger subsequent gaze-cueing effect following supraliminal eye contact compared to a no-contact condition. In contrast, the gaze-cueing effect was smaller in the subliminal eye-contact condition than in the no-contact condition. These findings suggest that the facilitation effect of eye contact on coordinating social attention depends on visual awareness. Furthermore, subliminal eye contact might have an impact on subsequent social attention processes that differ from supraliminal eye contact. This study highlights the need to further investigate the role of eye contact in implicit social cognition.

Combined attention controls complex behavior by suppressing unlikely events

Attention enables behavior by modulating both sensory inputs and task goals. Combining attentional resources from both of those sources exerts qualitatively large effects on manual performance. Here we tested how combined attention was represented in sensory processing, as reflected by the P1 component and associated activity in the alpha band. We measured performance and recorded EEG while participants' attention was engaged in an automated, endogenous, and combined (i.e., automated and endogenous) manner. Behavioral results replicated past reports with reliable effects of isolated automated and endogenous attention, as well as their qualitatively unique combined effect. ERP analyses indicated expected increases in P1 amplitude for validly relative to invalidly cued targets in automated and endogenous conditions. However, in the combined case, the P1 difference between validly relative to invalidly cued targets decreased. Analyses of target-locked alpha-band further revealed that this condition was associated with an increased synchrony in the alpha frequency for invalidly cued targets. This suggests that the large performance benefit observed when attentional systems combine is partly driven by suppressed processing of unexpected targets, dovetailing with the notion that in addition to increasing sensory gain of attended targets, attention may also modulate complex behavior by increasing suppression of unattended ones.

Atypical Processing of Gaze Cues and Faces Explains Comorbidity between Autism Spectrum Disorder (ASD) and Attention Deficit/Hyperactivity Disorder (ADHD)

This study investigated the neurobiological basis of comorbidity between autism spectrum disorder (ASD) and attention deficit/hyperactivity disorder (ADHD). We compared children with ASD, ADHD or ADHD+ASD and typically developing controls (CTRL) on behavioural and electrophysiological correlates of gaze cue and face processing. We measured effects of ASD, ADHD and their interaction on the EDAN, an ERP marker of orienting visual attention towards a spatially cued location and the N170, a right-hemisphere lateralised ERP linked to face processing. We identified atypical gaze cue and face processing in children with ASD and ADHD+ASD compared with the ADHD and CTRL groups. The findings indicate a neurobiological basis for the presence of comorbid ASD symptoms in ADHD. Further research using larger samples is needed.

Theta Oscillations Related to Orientation Recognition in Unattended Condition: A vMMN Study

Orientation is one of the important elements of objects that can influence visual processing. In this study, we examined whether changes in orientation could be detected automatically under unattended condition. Visual mismatch negativity (vMMN) was used to analyze this processing. In addition, we investigated the underlying neural oscillatory activity. Non-phase-locked spectral power was used to explore the specific frequency related to unexpected changes in orientation. The experiment consisted of standard (0° arrows) and deviant (90°/270° arrows) stimuli. Compared with standard stimuli, deviant stimuli elicited a larger N170 component (negative wave approximately 170 ms after the stimuli started) and a smaller P2 component (positive wave approximately 200 ms after the stimuli started). Furthermore, vMMN was obtained by subtracting the event-related potential (ERP) waveforms in response to standard stimuli from those elicited in response to deviant stimuli. According to the time–frequency analysis, deviant stimuli elicited enhanced band power compared with standard stimuli in the delta and theta bands. Compared with previous studies, we concluded that theta activity plays an important role in the generation of the vMMN induced by changes in orientation.

Neural Correlates of Expert Behavior During a Domain-Specific Attentional Cueing Task in Badminton Players

The present study aimed to investigate the neural correlates associated with sports expertise during a domain-specific task in badminton players. We compared event-related potentials activity from collegiate male badminton players and a set of matched athletic controls when they performed a badminton-specific attentional cueing task in which the uncertainty and validity were manipulated. The data showed that, regardless of cue type, the badminton players had faster responses along with greater P3 amplitudes than the athletic controls on the task. Specifically, the contingent negative variation amplitude was smaller for the players than for the controls in the condition involving higher uncertainty. Such an effect, however, was absent in the condition with lower uncertainty. We conclude that expertise in sports is associated with proficient modulation of brain activity during cognitive and motor preparation, as well as response execution, when performing a task related to an individual's specific sport domain.

Changes in predictive cuing modulate the hemispheric distribution of the P1 inhibitory response to attentional targets

Brain activity related to orienting of attention with spatial cues and brain responses to attentional targets are influenced the probabilistic contingency between cues and targets. Compared to predictive cues, cues predicting at chance the location of targets reduce the filtering out of uncued locations and the costs in reorienting attention to targets presented at these locations. Slagter et al. (2016) have recently suggested that the larger target related P1 component that is found in the hemisphere ipsilateral to validly cued targets reflects stimulus-driven inhibition in the processing of the unstimulated side of space contralateral to the same hemisphere. Here we verified whether the strength of this inhibition and the amplitude of the corresponding P1 wave are modulated by the probabilistic link between cues and targets. Healthy participants performed a task of endogenous orienting once with predictive and once with non-predictive directional cues. In the non-predictive condition we observed a drop in the amplitude of the P1 ipsilateral to the target and in the costs of reorienting. No change in the inter-hemispheric latencies of the P1 was found between the two predictive conditions. The N1 facilitatory component was unaffected by predictive cuing. These results show that the predictive context modulates the strength of the inhibitory P1 response and that this modulation is not matched with changes in the inter-hemispheric interaction between the P1 generators of the two hemispheres.

The Role of Global and Local Visual Information during Gaze-Cued Orienting of Attention

Gaze direction is an important social communication tool. Global and local visual information are known to play specific roles in processing socially relevant information from a face. The current study investigated whether global visual information has a primary role during gaze-cued orienting of attention and, as such, may influence quality of interaction. Adults performed a gaze-cueing task in which a centrally presented face cued (valid or invalid) the location of a peripheral target through a gaze shift. We measured brain activity (electroencephalography) towards the cue and target and behavioral responses (manual and saccadic reaction times) towards the target. The faces contained global (i.e. lower spatial frequencies), local (i.e. higher spatial frequencies), or a selection of both global and local (i.e. mid-band spatial frequencies) visual information. We found a gaze cue-validity effect (i.e. valid versus invalid), but no interaction effects with spatial frequency content. Furthermore, behavioral responses towards the target were in all cue conditions slower when lower spatial frequencies were not present in the gaze cue. These results suggest that whereas gaze-cued orienting of attention can be driven by both global and local visual information, global visual information determines the speed of behavioral responses towards other entities appearing in the surrounding of gaze cue stimuli.

Neural activity associated with attention orienting triggered by implied action cues

Spatial attention can be directed by the actions of others. We used ERPs method to investigate the neural underpins associated with attention orienting which is induced by implied body action. Participants performed a standard non-predictive cuing task, in which a directional implied action (throwing and running) or non-action (standing) cue was randomly presented and then followed by a target to the left or right of the central cue, despite cue direction. The cue-triggered ERPs results demonstrated that implied action cues, rather than the non-action cue, could shift the observers' spatial attention as demonstrated by the robust anterior directing attention negativity (ADAN) effects in throwing and running cues. Further, earlier N1 (100-170ms) and P2 (170-260ms) waveform differences occurred between implied action and non-action cues over posterior electrodes. The P2 component might reflect implied motion signal perception of implied action cues, and this implied motion perception might play an important role in facilitating the attentional shifts induced by implied action cues. Target-triggered ERPs data (mainly P3a component) indicated that implied action cues (throwing and running) speeded and enhanced the responses to valid targets compared to invalid targets. Furthermore, P3a might imply that implied action orienting may share similar mechanisms of action with voluntary attention, especially at the novel stimuli processing decision-level. These results further support previous behavioral findings that implied body actions direct spatial attention and extend our understanding about the nature of the attentional shifts that are elicited by implied action cues.

Increasing N200 Potentials Via Visual Stimulus Depicting Humanoid Robot Behavior

Achieving recognizable visual event-related potentials plays an important role in improving the success rate in telepresence control of a humanoid robot via N200 or P300 potentials. The aim of this research is to intensively investigate ways to induce N200 potentials with obvious features by flashing robot images (images with meaningful information) and by flashing pictures containing only solid color squares (pictures with incomprehensible information). Comparative studies have shown that robot images evoke N200 potentials with recognizable negative peaks at approximately 260[Formula: see text]ms in the frontal and central areas. The negative peak amplitudes increase, on average, from [Formula: see text]V, induced by flashing the squares, to [Formula: see text]V, induced by flashing the robot images. The data analyses support that the N200 potentials induced by the robot image stimuli exhibit recognizable features. Compared with the square stimuli, the robot image stimuli increase the average accuracy rate by 9.92%, from 83.33% to 93.25%, and the average information transfer rate by 24.56[Formula: see text]bits/min, from 72.18[Formula: see text]bits/min to 96.74 bits/min, in a single repetition. This finding implies that the robot images might provide the subjects with more information to understand the visual stimuli meanings and help them more effectively concentrate on their mental activities.

Deficient cortical face-sensitive N170 responses and basic visual processing in schizophrenia

BACKGROUND

Face detection, an ability to identify a visual stimulus as a face, is impaired in patients with schizophrenia. It is unclear whether impaired face processing in this psychiatric disorder results from face-specific domains or stems from more basic visual domains. In this study, we examined cortical face-sensitive N170 response in schizophrenia, taking into account deficient basic visual contrast processing.

METHODS

We equalized visual contrast signals among patients (n=20) and controls (n=20) and between face and tree images, based on their individual perceptual capacities (determined using psychophysical methods). We measured N170, a putative temporal marker of face processing, during face detection and tree detection.

RESULTS

In controls, N170 amplitudes were significantly greater for faces than trees across all three visual contrast levels tested (perceptual threshold, two times perceptual threshold and 100%). In patients, however, N170 amplitudes did not differ between faces and trees, indicating diminished face selectivity (indexed by the differential responses to face vs. tree).

CONCLUSION

These results indicate a lack of face-selectivity in temporal responses of brain machinery putatively responsible for face processing in schizophrenia. This neuroimaging finding suggests that face-specific processing is compromised in this psychiatric disorder.

Neural mechanisms underlying conscious and unconscious attentional shifts triggered by eye gaze

Behavioral studies have shown that eye gaze triggers attentional shifts both with and without conscious awareness. However, the neural substrates of conscious and unconscious attentional shifts triggered by eye gaze remain unclear. To investigate this issue, we measured brain activity using event-related functional magnetic resonance imaging while participants observed averted or straight eye-gaze cues presented supraliminally or subliminally in the central visual field and then localized a subsequent target in the peripheral visual field. Reaction times for localizing the targets were shorter under both supraliminal and subliminal conditions when eye-gaze cues were directionally congruent with the target locations than when they were directionally neutral. Conjunction analyses revealed that a bilateral cortical network, including the middle temporal gyri, inferior parietal lobules, anterior cingulate cortices, and superior and middle frontal gyri, was activated more in response to averted eyes than to straight eyes under both supraliminal and subliminal conditions. Interaction analyses revealed that the right inferior parietal lobule was specifically active when participants viewed averted eyes relative to straight eyes under the supraliminal condition; the bilateral subcortical regions, including the superior colliculus and amygdala, and the middle temporal and inferior frontal gyri in the right hemisphere were activated in response to averted versus straight eyes under the subliminal condition. These results suggest commonalities and differences in the neural mechanisms underlying conscious and unconscious attentional shifts triggered by eye gaze.

Photographic but not line-drawn faces show early perceptual neural sensitivity to eye gaze direction

Our brains readily decode facial movements and changes in social attention, reflected in earlier and larger N170 event-related potentials (ERPs) to viewing gaze aversions vs. direct gaze in real faces (Puce et al., 2000). In contrast, gaze aversions in line-drawn faces do not produce these N170 differences (Rossi et al., 2014), suggesting that physical stimulus properties or experimental context may drive these effects. Here we investigated the role of stimulus-induced context on neurophysiological responses to dynamic gaze. Sixteen healthy adults viewed line-drawn and real faces, with dynamic eye aversion and direct gaze transitions, and control stimuli (scrambled arrays and checkerboards) while continuous electroencephalographic (EEG) activity was recorded. EEG data from 2 temporo-occipital clusters of 9 electrodes in each hemisphere where N170 activity is known to be maximal were selected for analysis. N170 peak amplitude and latency, and temporal dynamics from Event-Related Spectral Perturbations (ERSPs) were measured in 16 healthy subjects. Real faces generated larger N170s for averted vs. direct gaze motion, however, N170s to real and direct gaze were as large as those to respective controls. N170 amplitude did not differ across line-drawn gaze changes. Overall, bilateral mean gamma power changes for faces relative to control stimuli occurred between 150–350 ms, potentially reflecting signal detection of facial motion. Our data indicate that experimental context does not drive N170 differences to viewed gaze changes. Low-level stimulus properties, such as the high sclera/iris contrast change in real eyes likely drive the N170 changes to viewed aversive movements.

Sex-Linked Mating Strategies Diverge with a Manipulation of Genital Salience

Trivers (1972) proposed that evolutionary factors should favor divergent mating strategies for males versus females. Such differences may be less pronounced among human beings than other animals and social norms and sex roles are also pertinent influences. The present experiment (N = 133 college undergraduates, 74 female) sought to bypass some of these other influences. Participants were randomly assigned to a condition designed to increase attention to the genital region (a downward pointing arrow) or not (an upward pointing arrow). They then reported on their interest in short-term (e.g., a one-night stand) and long-term (e.g., a potential marital partner) mating opportunities. A theory-consistent three-way interaction occurred such that the genital salience manipulation primed a shorter-term reproductive strategy among men and a longer-term reproductive strategy among women. The results provide unique support for evolution-linked ideas about sex differences in the form of a role for bodily attention.

The role of the oculomotor system in covert social attention

Observing a change in gaze direction triggers a reflexive shift of attention and appears to engage the eye-movement system. However, the functional relationship between social attention and this oculomotor activation is unclear. One extremely influential hypothesis is that the preparation of a saccadic eye movement is necessary and sufficient for a covert, reflexive shift of attention (the premotor theory of attention; Rizzolatti et al., 1994). Surprisingly, this theory has not been directly tested with respect to reflexive gaze cueing. In order to address this issue, gaze cueing, peripheral cueing, and arrow cueing were examined under conditions in which some stimuli appeared at locations that could not become the goal of a saccadic eye movement. It was observed that peripheral cues failed to elicit reflexive attentional orienting when targets appeared beyond the range of eye movements. Similarly, nonpredictive arrow cues were ineffective when targets could not become the goal of a saccade. In contrast, significant gaze-cueing effects were still observed when targets were beyond the range of eye movements. These data demonstrate that the mechanisms involved in gaze cueing are dissociated from those involved in exogenous orienting to peripheral or arrow cues. Furthermore, the findings suggest that, unlike peripheral cueing and reflexive arrow cueing, gaze cueing is independent of oculomotor control. We conclude that the premotor theory does not offer a compelling explanation for gaze cueing.