Perception最新文献

Search asymmetry has been called a "litmus test" for basic visual features. The letter Q is thought to contain a basic feature because (i) it can be found quickly, no matter how many O's it is hiding amongst and (ii) it is much harder to find an O amongst Q's. We tested the possibility that a basic visual feature is created when two perpendicular Gabor patterns are superimposed to form a "plaid." We found relatively large effects of set size on reaction time whenever participants tried to find a Gabor hiding among plaids. Set-size effects were smaller when participants tried to find a 2- or 4-cycle-per-degree plaid that was hiding among its component Gabors. The implication is that these plaids contain a basic visual feature, which is not present in its component Gabors. This feature may be an intrinsic two-dimensionality that is extracted from the visual intensity map. Mixed-frequency plaids did not pop out from their component Gabors. This last result suggests that the visual system separates intrinsically two-dimensional image regions (e.g., corners and junctions) from intrinsically one-dimensional image regions (e.g., straight edges) after the scene is segregated into parallel spatial frequency channels.

This study renders the visual saltation illusion (VSI) into an expansion and a contraction transformation mode, diverging from traditional experiments using translation. Small-, medium-, and large-sized stimuli were used to create conditions akin to VSI translation experiments. Participants fixated on a cross while three stimuli (expanding or contracting) flashed 25.9° below. Despite actual size, observers consistently misperceived the second flash as medium-sized relative to the first and third flash. Further experiments were conducted to determine whether stimulus duration or interstimulus interval had more of an effect inducing the VSI. These results showed that for expansion and contraction, the VSI did not favor either parameter, but overall favored short stimulus onset asynchronies below 317 ms. These findings shed more light on the VSI phenomenon and open the doors on presenting the VSI in other modes.

The composite face effect (CFE) provides evidence for holistic face processing by demonstrating that when halves of different faces are aligned to resemble a single face, recognition of the component identities is disrupted. However, if the face halves are misaligned, the component identities become easier to recognise. While the horizontal CFE - wherein the top and bottom halves of the face are aligned - has been extensively studied, the existence of a vertical CFE - involving the combination of left-right face halves - remains unclear. This study investigated the vertical CFE using composite stimuli created by pairing familiar and unfamiliar faces. Participants made familiarity judgements for aligned and misaligned vertical and horizontal composites. Familiarity judgements were made more accurately and with faster response times with misaligned compared to aligned composites. The magnitude of the vertical CFE was comparable to the horizontal CFE and was unaffected by identity priming or which half of the face was attended. However, the size of the CFE was reduced when attention was not directed to a specific face half. These findings suggest that both the vertical and horizontal CFE reflect a common mechanism for integrating facial information across the visual field, underscoring holistic processing as a fundamental process in face recognition.

The effect of face orientation and exposure duration on facial identity recognition and matching are well-documented but has scarcely been examined for facial age perception. Using a facial age categorisation task (i.e., classifying faces as over and under the age of 18) with ambient faces, we manipulated facial orientation (upright and inverted) and exposure duration (250 and 2000 ms) to examine their unique and interactive effects on age classification accuracy. Across two experiments, age classification accuracy was impaired by inverting faces. Additionally, overall accuracy was improved when participants were required to view the faces for the full length of the long duration (2000 ms) (experiment 2), but not when they had the opportunity to respond earlier than the end of stimuli (experiment 1). However, there was no interactive effect of exposure duration and facial orientation. These findings suggest that accurate age classification relies on facial information that is disrupted when inverted.

Multisensory processing critically depends on the perceived timing of stimuli in the different sensory modalities. Crossmodal stimuli that fall within rather than outside an individual temporal binding window (TBW) are more likely to be bound into a multisensory percept. A number of studies have shown that a short perceptual training in which participants receive feedback on their responses in an audiovisual simultaneity judgment (SJ) task can substantially decrease the size of the TBW and hence increase crossmodal temporal acuity. Here we tested whether multisensory perceptual learning in the SJ task is specific for the spatial locations at which the audiovisual stimuli are presented during training. Participants received feedback about the correctness of their SJ responses for audiovisual stimuli which were presented in one hemifield only. The TBW was assessed separately for audiovisual stimuli in each hemifield before and one day after the training. In line with previous findings, the size of the TBW was significantly reduced after the training phase. Importantly, an equally strong reduction of TBW size was observed in both the trained and the untrained hemifield. Thus, multisensory temporal learning completely generalized to the untrained hemifield, suggesting that the improvement in crossmodal temporal acuity was mediated by higher, location-invariant processing stages. These findings have implications for the design of multisensory training protocols in applied settings such as clinical interventions by showing that training at multiple spatial locations might not be necessary to achieve robust improvements in crossmodal temporal acuity.

Vection is an illusion of self-motion that arises from conflicting sensory information. There are large individual differences in experiencing vection, indicating a potential role for individual-difference factors in this illusion. Here, we examined the role of field dependence, anomalous perceptual experiences (a specific domain of psychotic-like experiences) and personality disposition of tolerance of ambiguity. We analyzed data from 170 participants (84 male individuals, 86 female individuals). Biological sex had no significant effect on any of the vection measures. However, we found that higher field dependence was associated with faster onset of vection, and that higher prevalence of anomalous perceptual experiences and lower tolerance of ambiguity were associated with longer duration and higher intensity of the illusion. These results suggest that individual-difference factors reflect internal predispositions that guide the interpretation of incoming sensory signals and, especially in conflicting and ambiguous situations, can modulate the process of creating accurate or illusory percepts.

In the Critique of Pure Reason, Kant proposed a detailed system of mental processes and constructs that might lead to a person's perceiving and comprehending an object in the outside world. The diffuse and extended original, found largely impenetrable and hence neglected in most modern discourse, is here revisited and presented in an updated contemporary idiom, with the aim of showing some structure in the mental world that may serve as a counterpart to definable states of the real world when attempts are made to find correlations between the two.

Research has shown that individuals detect direct eyes (those directed to the observer) more quickly and accurately than averted eyes (those directed elsewhere), a phenomenon known as the direct-gaze advantage. However, the underlying mechanisms of this advantage remain poorly understood. The current study employed a visual search task to investigate whether the direct-gaze advantage in capturing attention is contingent upon a specific configuration (face configuration or eyes configuration). In two experiments, participants were presented with four images and asked to judge whether there was a target with a direct or averted gaze. Experiment 1 revealed that participants showed the direct-gaze advantage across three image types: intact faces (maintaining both two-eye and face configuration), scrambled faces with intact eyes (disrupting the face configuration while preserving the two-eye configuration), and fully scrambled faces (preserving only the single-eye configuration). Experiment 2 further demonstrated that participants showed the direct-gaze advantage for scrambled faces with intact eyes and fully scrambled faces under the upright condition. Interestingly, under the inverted condition, participants only showed the direct-gaze advantage for scrambled faces with intact eyes. These findings indicate that the direct-gaze advantage is influenced by the configuration of two eyes and the configuration of a single eye, but it is not dependent on facial contexts.