Jan Zwickel

I See What You Mean: How Attentional Selection Is Shaped by Ascribing Intentions to Others

The ability to understand and predict others’ behavior is essential for successful interactions. When making predictions about what other humans will do, we treat them as intentional systems and adopt the intentional stance, i.e., refer to their mental states such as desires and intentions. In the present experiments, we investigated whether the mere belief that the observed agent is an intentional system influences basic social attention mechanisms. We presented pictures of a human and a robot face in a gaze cuing paradigm and manipulated the likelihood of adopting the intentional stance by instruction: in some conditions, participants were told that they were observing a human or a robot, in others, that they were observing a human-like mannequin or a robot whose eyes were controlled by a human. In conditions in which participants were made to believe they were observing human behavior (intentional stance likely) gaze cuing effects were significantly larger as compared to conditions when adopting the intentional stance was less likely. This effect was independent of whether a human or a robot face was presented. Therefore, we conclude that adopting the intentional stance when observing others’ behavior fundamentally influences basic mechanisms of social attention. The present results provide striking evidence that high-level cognitive processes, such as beliefs, modulate bottom-up mechanisms of attentional selection in a top-down manner.

Exploring the building blocks of social cognition: spontaneous agency perception and visual perspective taking in autism

Individuals with autism spectrum disorders have highly characteristic impairments in social interaction and this is true also for those with high functioning autism or Asperger syndrome (AS). These social cognitive impairments are far from global and it seems likely that some of the building blocks of social cognition are intact. In our first experiment, we investigated whether high functioning adults who also had a diagnosis of AS would be similar to control participants in terms of their eye movements when watching animated triangles in short movies that normally evoke mentalizing. They were. Our second experiment using the same movies, tested whether both groups would spontaneously adopt the visuo-spatial perspective of a triangle protagonist. They did. At the same time autistic participants differed in their verbal accounts of the story line underlying the movies, confirming their specific difficulties in on-line mentalizing. In spite of this difficulty, two basic building blocks of social cognition appear to be intact: spontaneous agency perception and spontaneous visual perspective taking.

The effect of fearful faces on the attentional blink is task dependent.

In a set of three rapid serial visual presentation experiments, we investigated the effect of fearful and neutral face stimuli on the report of trailing scene targets. When the emotional expression of the face stimuli had to be indicated, fearful faces induced a stronger attentional blink (AB) than did neutral faces. However, with identical physical stimulation, the enhancement of the AB by fearful faces disappeared when participants had to judge the faces’ gender. If faces did not have to be reported, no AB was observed. Thus, fearful faces exhibited an effect on the AB that crucially depended on the observer’s attentional set. Hence, the AB can be influenced by an emotional T1 when T1 has to be reported, but this influence is modulated by task context. This result indicates a close connection between temporal attention and emotional processing that is modulated by task context.

Animated triangles: an eye tracking investigation.

We presented three types of animations on an eye tracking monitor to 31 adult participants. In line with previous work, verbal descriptions of these animations indicate that one type (theory of mind or ToM) evokes mental state attributions, while another type (random) does not, with an intermediate category (goal-directed) evoking a moderate amount of mental state attributions. We expected longer fixations with greater depth of processing, which we assume is required for mental state attributions. In line with this expectation we found that the ToM animations invited long fixations; the random animations invited short fixations, while the goal-directed animations invited an intermediate amount of fixations, with some clips inviting shorter and others longer fixations. These findings demonstrate that it is possible to capture systematic differences in behaviour while viewing animations not only by means of a verbal measure, but also in terms of a simple measure of eye movements.

Agency Attribution and Visuospatial Perspective Taking

We tested whether processes that evoke agency interpretations and mental state attributions also lead to adoption of the actor’s visuospatial perspective by the observer. Agency and mental state interpretations were manipulated by showing different film clips involving two triangles (the Frith-Happé animations). Participants made speeded spatial decisions while watching these films. The responses in the spatial task could be either the same or different when given from the perspective of the participant versus the perspective of one of the triangles. Reaction times were longer when the perspectives of the participants and triangles differed than when they were the same. This effect increased as the need to invoke agency interpretations in order to understand the films increased, and it increased for those films that had previously been shown to evoke mental state attributions. This demonstrates that processing of an agent’s behavior co-occurs with perspective adoption, even in the case in which triangles are the actors.

How the presence of persons biases eye movements

We investigated modulation of gaze behavior of observers viewing complex scenes that included a person. To assess spontaneous orientation-following, and in contrast to earlier studies, we did not make the person salient via instruction or low-level saliency. Still, objects that were referred to by the orientation of the person were visited earlier, more often, and longer than when they were not referred to. Analysis of fixation sequences showed that the number of saccades to the cued and uncued objects differed only for saccades that started from the head region, but not for saccades starting from a control object or from a body region. We therefore argue that viewing a person leads to an increase in spontaneous following of the person’s viewing direction even when the person plays no role in scene understanding and is not made prominent.

The importance of context information for the spatial specificity of gaze cueing

In three experiments, we investigated the spatial allocation of attention in response to central gaze cues. In particular, we examined whether the allocation of attentional resources is influenced by context information—that is, the presence or absence of reference objects (i.e., placeholders) in the periphery. On each trial, gaze cues were followed by a target stimulus to which participants had to respond by keypress or by performing a target-directed saccade. Targets were presented either in an empty visual field (Exps. 1 and 2) or in previewed location placeholders (Exp. 3) and appeared at one of either 18 (Exp. 1) or six (Exps. 2 and 3) possible positions. The spatial distribution of attention was determined by comparing response times as a function of the distance between the cued and target positions. Gaze cueing was not specific to the exact cued position, but instead generalized equally to all positions in the cued hemifield, when no context information was provided. However, gaze direction induced a facilitation effect specific to the exact gazed-at position when reference objects were presented. We concluded that the presence of possible objects in the periphery to which gaze cues could refer is a prerequisite for attention shifts being specific to the gazed-at position.

Irrelevant Words Trigger an Attentional Blink

It has been argued that salient distractor items displayed during rapid serial visual presentation (RSVP) trigger an attentional blink (AB) when they share features with the target item. Here we demonstrate that salient distractor words induce an AB independently of feature overlap with the target. In two experiments a color-highlighted irrelevant word preceded a target by a variable lag in an RSVP series of false font strings. Target identification was reduced at short relative to long temporal lags between the distractor word and the target, irrespective of feature sharing with the distractor word. When the target shared features with the distractor word, target accuracy was reduced across all lags. Accordingly, feature sharing between the distractor word and the target did not amplify the AB, but had an additive effect on attentional capture by the distractor word.

Influences of spontaneous perspective taking on spatial and identity processing of faces

Previous research suggests that people, when interacting with another agent, are sensitive to the others visual perspective on the scene. The present study investigated how spontaneously anothers different spatial perspective is taken into account and how this affects the processing of jointly attended stimuli. Participants viewed upright or inverted faces alone, next to another person (same spatial perspective), or opposite another person (different spatial perspectives) while electroencephalography (EEG) was recorded. The task (counting male faces) was in no way related to spatial aspects of the stimuli, and thus did not encourage perspective taking. EEG results revealed no general differences between viewing faces alone or with another person. However, when holding different perspectives (sitting opposite each other), the amplitudes of the N170 and of the N250 significantly increased for upright faces. This indicates that people spontaneously represented the others different perspective, which led to higher demands for structural encoding (N170) and to increased allocation of attention to face recognition (N250) for stimuli that are typically processed configurally. When holding different spatial perspectives, thus, people may not merely represent that the other sees the object or scene differently, but how the object/scene looks for the other.

Has someone moved my plate? The immediate and persistent effects of object location changes on gaze allocation during natural scene viewing

In this study, we investigated the immediate and persisting effects of object location changes on gaze control during scene viewing. Participants repeatedly inspected a randomized set of naturalistic scenes for later questioning. On the seventh presentation, an object was shown at a new location, whereas the change was reversed for all subsequent presentations of the scene. We tested whether deviations from stored scene representations would modify eye movements to the changed regions and whether these effects would persist. We found that changed objects were looked at longer and more often, regardless of change reportability. These effects were most pronounced immediately after the change occurred and quickly leveled off once a scene remained unchanged. However, participants continued to perform short validation checks to changed scene regions, which implies a persistent modulation of eye movement control beyond the occurrence of object location changes.