Paranormal believers are more prone to illusory agency detection than skeptics

It has been hypothesized that illusory agency detection is at the basis of belief in supernatural agents and paranormal beliefs. In the present study a biological motion perception task was used to study illusory agency detection in a group of skeptics and a group of paranormal believers. Participants were required to detect the presence or absence of a human agent in a point-light display. It was found that paranormal believers had a lower perceptual sensitivity than skeptics, which was due to a response bias to ‘yes’ for stimuli in which no agent was present. The relation between paranormal beliefs and illusory agency detection held only for stimuli with low to intermediate ambiguity, but for stimuli with a high number of visual distractors responses of believers and skeptics were at the same level. Furthermore, it was found that illusory agency detection was unrelated to traditional religious belief and belief in witchcraft, whereas paranormal beliefs (i.e. Psi, spiritualism, precognition, superstition) were strongly related to illusory agency detection. These findings qualify the relation between illusory pattern perception and supernatural and paranormal beliefs and suggest that paranormal beliefs are strongly related to agency detection biases.     

How children with facial differences are perceived by non-affected children and adolescents: Perceiver effects on stereotypical attitudes

Children with a facial difference are presumed to be at risk of social stigmatization. The purposes of this study were twofold: (1) to assess the effect of facial differences on social perceptions by unaffected children and adolescents; and (2) to identify perceiver characteristics that predict stereotypical attitudes toward facial differences. Participants were 344 non-affected children and adolescents, ages 8–17 years. Participants rated digitally altered images of 12 children depicted either with or without a facial difference. Results show that participants attributed less favorable characteristics to children with a facial difference than to those without. Moreover, participants reported less willingness to interact with or befriend a child with a facial difference. Significant predictors of low discriminative attitudes were older participant age and previous contact with someone with a facial difference. Our data call attention to the need for public education programs targeted at reducing negative attitudes toward facial differences.     

Concurrent Directional Adaptation of Reactive Saccades and Hand Movements to Target Displacements of Different Size

When eye and hand movements are concurrently aimed at double-step targets that call for equal and opposite changes of response direction (–10° for the eyes, +10° for the hand), adaptive recalibration of both motor systems is strongly attenuated; instead, hand but not eye movements are changed by corrective strategies (V. Grigorova et al., 2013a). The authors introduce a complementary paradigm, where double-step targets call for a –10° change of eye and a ?30° change for hand movements. If compared to control subjects adapting only the eyes or only the hand, adaptive improvements were comparable for the eyes but were twice as large for the hand; in contrast, eye and hand aftereffects were comparable to those in control subjects. The authors concluded that concurrent exposure of eyes and hand to steps of the same direction but different size facilitated hand strategies, but didn't affect recalibration. This finding together with previous one (V. Grigorova et al., 2013a), suggests that concurrent adaptation of eyes and hand reveals different mechanisms of recalibration for step sign and step size, which are shared by reactive saccades and hand movements. However, hand mostly benefits from strategies provoked by the difference in target step sign and size.     

Is social inhibition of return due to action co-representation?

When two individuals alternate reaching responses to visual targets presented on a shared workspace, one individual is slower to respond to targets occupying the same position as their partner’s previous response. This phenomenon is thought to be due to processes that inhibit the initiation of a movement to a location recently acted upon. However, two distinct forms of the inhibition account have been posited, one based on inhibition of an action, the other based on inhibition of an action and location. Furthermore, an additional recent explanation suggests the phenomenon is due to mechanisms that give rise to action congruency effects. Thus the three different theories differ in the degree to which action co-representation plays a role in the effect. The aim of the present work was to examine these competing accounts. Three experiments demonstrated that when identical actions are made, the effect is modulated by the configuration of the visual stimuli acted upon and the perceptual demands of the task. In addition, when the co-actors perform different actions to the same target, the effect is still observed. These findings support the hypothesis that this particular joint action phenomenon is generated via social cues that induce location-based inhibition of return rather than being due to shared motor co-representations.     

Temporal structure coding with and without awareness

In order to interpret a constantly changing environment, visual events far apart in space and time must be integrated into a unified percept. While spatial properties of invisible signals are known to be encoded without awareness, the fate of temporal properties remains largely unknown. Here, we probed temporal integration for two distinct motion stimuli that were either visible or rendered invisible using continuous flash suppression. We found that when invisible, both the direction of apparent motion and the gender of point-light walkers were processed only when defined across short time periods (i.e., respectively 100 ms and 1000 ms). This limitation was not observed under full visibility. These similar findings at two different hierarchical levels of processing suggest that temporal integration windows shrink in the absence of perceptual awareness. We discuss this phenomenon as a key prediction of the global neuronal workspace and the information integration theories of consciousness.     

Differential activation of a central inhibition system by motion and colour distractors

ABSTRACT

The selection of relevant stimuli is partially achieved through inhibition of irrelevant distractors. Using the distractor induced blindness (DIB) paradigm, we investigated whether these inhibitory processes depend on the feature dimension that is used to define distractors. Following a pilot study that found motion and colour targets to be comparably salient, we analysed distractor effects of those two feature dimensions. In both feature dimensions, an inhibition effect depended on the number of distractors. Colour, however, was more sensitive to distractor episodes as compared to motion: The level of inhibition was more pronounced, and its activation required less distractors. The results of a control experiment provided further evidence that, in fact, the feature dimension -instead of design differences between tasks- is responsible for this observation. The dimension-sensitive bias in the activation of a central inhibition system may be attributed to a differential processing of visual signals, depending on their behavioural relevance.     

Left-view sequences of faces are superior to right-view ones for view generalization

Faces learned from multiple viewpoints are recognized better with left than right three-quarter views. This left-view superiority could be explained by perceptual experience, facial asymmetry, or hemispheric specialization. In the present study, we investigated whether left-view sequences are also more effective in recognizing same and novel views of a face. In a sequential matching task, a view sequence showing a face rotating around a left (?30°) or a right (+30°) angle, with an amplitude of 30°, was followed by a static test view with the same viewpoint as the sequence (?30° or +30°) or with a novel one (0°, +30°, or ?30°). We found a superiority of left-view sequences independently of the test viewpoint, but no superiority of left over right test views. These results do not seem compatible with the perceptual experience hypothesis, which predicts superiority only for left-side test views (?30°). Also, a facial asymmetry judgement task showed no correlation between the asymmetry of individual faces and the left-view sequence superiority. A superiority of left-view sequences for novel as well as same test views argues in favour of an explanation by hemispheric specialization, because of the possible role of the right hemisphere in extracting facial identity information.     

Temporal perception is enhanced for goal-directed biological actions

ABSTRACT

Research into the visual perception of goal-directed human action indicates that human action perception makes use of specialized processing systems, similar to those that operate in visual expertise. Against this background, the current research investigated whether perception of temporal information in goal-directed human action is enhanced relative to similar motion stimuli. Experiment 1 compared observers’ sensitivity to speed changes in upright human action to a kinematic control (an animation yoked to the motion of the human hand), and also to inverted human action. Experiment 2 compared human action to a non-human motion control (a tool moved the object). In both experiments observers’ sensitivity to detecting the speed changes was higher for the human stimuli relative to the control stimuli, and inversion in Experiment 1 did not alter observers’ sensitivity. Experiment 3 compared observers’ sensitivity to speed changes in goal-directed human and dog actions, in order to determine if enhanced temporal perception is unique to human actions. Results revealed no difference between human and dog stimuli, indicating that enhanced speed perception may exist for any biological motion. Results are discussed with reference to theories of biological motion perception and perception in visual expertise.     

Faces as perceptual wholes: The interplay between component and configural properties in face processing

The relative dominance of component and configural properties in face processing is a controversial issue. We examined this issue by testing whether the discriminability of components predicts the discrimination of faces with similar versus dissimilar configurations. Discrimination of faces with similar configurations was determined by components discriminability, indicating independent processing of facial components. The presence of configural variation had no effect on discriminating faces with highly discriminable components, suggesting that discrimination was based on the components. The presence of configural variation, however, facilitated the discrimination of faces with more difficult-to-discriminate components, above and beyond what would be predicted by the configural or componential discriminability, indicating interactive processing. No effect of configural variation was observed in discriminating inverted faces. These results suggest that both component and configural properties contribute to the processing of upright faces and no property necessarily dominates the other. Upright face discrimination can rely on components, configural properties, or interactive processing of component and configural properties, depending on the information available and the discriminability of the properties. Inverted faces are dominated by componential processing. The finding that interactive processing of component and configural properties surfaced when the properties were of similar, not very high discriminability, suggests that such interactive processing may be the dominant form of face processing in everyday life.     

Angry faces hold the eyes

Efficient processing of complex social and biological stimuli associated with threat is crucial for survival. Previous studies have suggested that threatening stimuli such as angry faces not only capture visual attention, but also delay the disengagement of attention from their location. However, in the previous studies disengagement of attention was measured indirectly and was inferred on the basis of delayed manual responses. The present study employed a novel paradigm that allows direct examination of the delayed disengagement hypothesis by measuring the time it takes to disengage the eyes from threatening stimuli. The results showed that participants were indeed slower to make an eye movement away from an angry face presented at fixation than from either a neutral or a happy face. This finding provides converging support that the delay in disengagement of attention is an important component of processing threatening information.