What's the point? Infants' and adults' perception of different pointing gestures

Adults and infants as young as 4 months old follow pointing gestures. Although adults are shown to orient faster to index-finger pointing compared to other hand shapes, it is not known whether hand shapes influence infants' following of pointing. In this study, we used a spatial cueing paradigm on an eye tracker to investigate whether and to what extent adults and 12-month-old infants orient their attention in the direction of pointing gestures with different hand shapes: index finger, whole hand, and pinky finger. Results revealed that adults showed a cueing effect, that is, shorter saccadic reaction times (SRTs) to congruent compared to incongruent targets, for all hand shapes. However, they did not show a larger cueing effect triggered by the index finger. This contradicts previous findings and is discussed with respect to the differences in methodology. Infants showed a cueing effect only for the whole hand but not for the index finger or the pinky finger. Infants predominantly point with the whole hand prior to 12 months. The current results thus suggest that infants' perception of pointing gestures may be linked to their own production of pointing gestures. Infants may show a cueing effect by the conventional index-finger pointing shape later than their first year, possibly when they start to point predominantly with their index finger.

The Effect of Cue Labeling in Multimedia Learning: Evidence From Eye Tracking

Cue labels are useful during multimedia learning. According to spatial contiguity principle, people learn more when related words and pictures are displayed spatially near one another. Well-arranged labels of multimedia material can greatly facilitate learning. This study used eye tracking to examine the joint influence of label size (large vs. small) and color (included vs. not) on multimedia learning. The results revealed that larger labels led to better retention test performance and a higher AOI glance count, but no cueing effect was found for color. Cues have a certain attention-leading function that promotes the learner remembering the content. These findings suggest that salient labels that provide explanatory information can guide learners’ attention and facilitate learning, though a combination of label size and color salience did not demonstrate a superior cueing effect.

Task-Irrelevant Context Learned Under Rapid Display Presentation: Selective Attention in Associative Blocking

In the contextual cueing task, visual search is faster for targets embedded in invariant displays compared to targets found in variant displays. However, it has been repeatedly shown that participants do not learn repeated contexts when these are irrelevant to the task. One potential explanation lays in the idea of associative blocking, where salient cues (task-relevant old items) block the learning of invariant associations in the task-irrelevant subset of items. An alternative explanation is that the associative blocking rather hinders the allocation of attention to task-irrelevant subsets, but not the learning per se. The current work examined these two explanations. In two experiments, participants performed a visual search task under a rapid presentation condition (300 ms) in Experiment 1, or under a longer presentation condition (2,500 ms) in Experiment 2. In both experiments, the search items within both old and new displays were presented in two colors which defined the irrelevant and task-relevant items within each display. The participants were asked to search for the target in the relevant subset in the learning phase. In the transfer phase, the instructions were reversed and task-irrelevant items became task-relevant (and vice versa). In line with previous studies, the search of task-irrelevant subsets resulted in no cueing effect post-transfer in the longer presentation condition; however, a reliable cueing effect was generated by task-irrelevant subsets learned under the rapid presentation. These results demonstrate that under rapid display presentation, global attentional selection leads to global context learning. However, under a longer display presentation, global attention is blocked, leading to the exclusive learning of invariant relevant items in the learning session.

Awareness-dependent normalization framework of visual bottom-up attention

Although bottom-up attention can improve visual performance with and without awareness, whether they are governed by a common neural computation remains unclear. Using a modified Posner paradigm with backward masking, we found that both the attention-triggered cueing effect with and without awareness displayed a monotonic gradient profile (Gaussian-like). The scope of this profile, however, was significantly wider with than without awareness. Subsequently, for each subject, the stimulus size was manipulated as their respective mean scopes with and without awareness while stimulus contrast was varied in a spatial cueing task. By measuring the gain pattern of contrast-response functions, we observed changes in the cueing effect consonant with changes in contrast gain for bottom-up attention with awareness and response gain for bottom-up attention without awareness. Our findings indicate an awareness-dependent normalization framework of visual bottom-up attention, placing a necessary constraint, namely, awareness, on our understanding of the neural computations underlying visual attention.

To follow or not to follow your gaze: The interplay between strategic control and the eye contact effect on gaze-induced attention orienting.

Eye contact constitutes a strong communicative signal in human interactions and has been shown to modulate various cognitive processes and states. However, little is known about its impact on gaze-mediated attentional orienting in the context of its interplay with strategic top-down control. Here, we aimed at investigating how the social component of eye contact interacts with the top-down strategic control. To this end, we designed a gaze cueing paradigm with iCub humanoid robot, in which iCub either established eye contact with the participants before averting its gaze or avoided their eyes. Across four experiments, we manipulated gaze cue validity to either elicit strategic top-down inhibitory activity (25% validity) or to allow for relaxing the control mechanisms (50% validity). Also, we manipulated the stimulus-onset-asynchrony (SOA) to examine the dynamics of the top-down modulatory effects. Our results showed that eye contact influenced the gaze cueing effect when the strategic control was not required, by prolonging the prioritized processing of the gazed-at locations. Thus, the effect was observed only when the measurement was taken after a sufficient amount of time (1000 ms SOA). However, when inhibitory control was necessary (25% validity), the social component was not potent enough to exert influence over the gaze cueing effect independently. Overall, we propose that strategic top-down control is the primary driving force over the gaze cueing effect and that the social aspect plays a modulatory effect by prolonging prioritized processing of gazed-at locations.

EXPRESS: The interplay between gaze cueing and facial trait impressions

The gaze cueing effect involves the rapid orientation of attention to follow the gaze direction of another person. Previous studies reported reciprocal influences between social variables and the gaze cueing effect, with modulation of gaze cueing by social features of face stimuli and modulation of the observer’s social judgments from the validity of the gaze cues themselves. However, it remains unclear which social dimensions can affect - and be affected by - gaze cues. We used computer-averaged prototype face-like images with high and low levels of perceived trustworthiness and dominance to investigate the impact of these two fundamental social impression dimensions on the gaze cueing effect. Moreover, by varying the proportions of valid and invalid gaze cues across three experiments, we assessed whether gaze cueing influences observers' impressions of dominance and trustworthiness through incidental learning. Bayesian statistical analyses provided clear evidence that the gaze cueing effect was not modulated by facial social trait impressions (Experiments 1-3). On the other hand, there was uncertain evidence of incidental learning of social evaluations following the gaze cueing task. A decrease in perceived trustworthiness for non-cooperative low dominance faces (Experiment 2) and an increase in dominance ratings for faces whose gaze behaviour contradicted expectations (Experiment 3) appeared, but further research is needed to clarify these effects. Thus, this study confirms that attentional shifts triggered by gaze direction involve a robust and relatively automatic process, which could nonetheless influence social impressions depending on perceived traits and the gaze behaviour of faces providing the cues.