Journal of Vision最新文献

The contextual cueing effect-where participants search repeated displays faster than novel ones-is often explained by the "attention guidance" account, which posits that repeated exposure helps individuals learn the context and attend to the likely target locations. Alternatively, the "generic procedural learning" account suggests that a general search strategy is developed for all displays, although repeated contexts play a higher weight in optimizing the strategy due to their higher presented frequency. This makes responses faster for repeated displays than novel displays. The current study examined these two mechanisms using a varied contextual cueing paradigm to analyze response time (RT) variability with the coefficient of variation (CV) and time-frequency analysis of RTs. Experiment 1 involved uninterrupted training with repeated and novel displays presented separately, followed by a test with randomly interleaved repeated and novel displays. Experiment 2 used interleaved displays for training before an uninterrupted test phase. Both experiments revealed faster RTs and reduced template-based variability for repeated displays early in the training, supporting attentional guidance. However, generic procedural learning, indicated by a late onset of lower cross-display variability for repeated displays, required more time and training to validate the cueing effect. These findings suggest that attentional guidance dominates early learning, but both mechanisms contribute to the contextual cueing effect overall.

Visual working memory (VWM) is characterized as extremely capacity limited. This finding is supported by the dramatic decline in change detection performance beyond a small number of items, as well as the observation of flat error distributions in delayed-estimation tasks. However, continuous resource models predict that small amounts of memory resources can be distributed to items at the expense of memory resolution (resulting in low response precision). These low-resolution memory representations should have nearly flat error distributions that could appear indistinguishable from uniform guessing distributions. In the current study, memory resource allocation was manipulated by varying the probability of an item being probed at recall. Responses were intermixed between continuous response and two-alternative forced-choice (2AFC) trials to examine whether these low-probability items could produce above-chance performance, consistent with them being held in memory. For comparison with the distribution of continuous responses, the magnitude of the discrimination between the target and lure colors was manipulated. Accuracy on the 2AFC trials was sensitive to both discrimination difficulty and probe probability manipulations. Critically, above-chance performance was found in the lowest probe probability condition (10% probe probability, equivalent to an item load of 10), suggesting that this condition had low-resolution memory representations rather than no memory representations. These findings are consistent with the predictions of continuous resource models and applications of signal detection models of VWM.

The Pulfrich effect is an illusion characterized by the misperception of the depth and 3D direction of moving objects. Interocular luminance differences cause the classic Pulfrich effect; the darker image is processed more slowly. Interocular blur differences cause the reverse Pulfrich effect; the blurrier image is processed more quickly. A common correction for presbyopia-monovision-intentionally induces the optical conditions that cause the reverse Pulfrich effect. The effect sizes, and the fact that tens of millions of people wear these corrections every day, raise concerns about public safety. However, although the impact of overall light level (e.g., nighttime vs. daytime) on the classic Pulfrich effect has been well characterized, its impact on the reverse Pulfrich effect is unknown. Here, using a custom binocular 4f tunable lens optical system that allows the decoupling of retinal illuminance and retinal blur, we report how the classic and reverse Pulfrich effects scale with overall light level. Both effects increase logarithmically with decreases in light level. These results motivate a characterization of how light level interacts with other optical factors (e.g., higher-order aberrations) that are likely to impact the reverse Pulfrich effect and, hence, the perceptual consequences of monovision corrections.

In crowding, perception of a target deteriorates in the presence of nearby elements. As the entire stimulus configuration across large parts of the visual field influences crowding and not just nearby elements, low-level explanations, such as local pooling, do not suffice. To explain the effects of stimulus configuration, grouping was proposed as the key, and we implemented these ideas in a neural network model (LAMINART). In a recent publication, Moore and Zheng (2024) used a set of stimuli designed to induce surface completion cues, such as occlusion, and found that they had no effect on crowding. Based on these results, the authors questioned the role of grouping in crowding. Here we show that the stimuli Moore and Zheng used do not induce the intended perceptual occlusion effects. Hence, their conclusions are not warranted. Additionally, simulations of the LAMINART model explain the results of Moore and Zheng with the existing model characteristics.

When a rotating grating reverses its direction and is accompanied by a briefly flashed stimulus on top, the flash's apparent position shifts in direction after the reversal. This phenomenon, termed the flash-grab effect, can induce an illusory position shift of several degrees of visual angle, prompting investigation into scenarios in which the expected position coincides with another visual event. We investigated two such situations: perceptual filling-in at the blind spot and amodal completion behind a visible occluder. By inducing a position shift in the flash presented just outside such completed patterns, we measured the perceived angular position of the flash in the perceptual matching paradigm. We found subjective localization within the completed region of the moving inducer. Consistent results were found even when the flash was presented at a less optimal time for the flash-grab effect. Illusion size had a certain dependency on stimulus configuration, suggesting that various sources of spatial referencing are involved in the position processing around the blind-spot/occluder region. These findings imply that the visual system does not necessarily avoid a region that is devoid of physical motion stimuli when determining perceived flash position, reaching a consistent perceptual solution that integrates the motion-induced position shift and perceptual completion.

The perception of ambiguous stimuli, notably binocular rivalry (BR), has been demonstrated to be influenced by spatial context. Previous results are, however, inconsistent with regard to whether the context biases perception toward the BR target that matches the context or toward the one that differs from the context. Furthermore, it is unclear what roles the perceptual ambiguity of the context and its lateral location play. We varied ambiguity, contrast, size, and location (left/right) of the context surrounding a rivalry target in a high-powered within-subject design to investigate (1) the effects of contrast and ambiguity of the surrounding context and (2) whether we could find laterality effects that correlated with an established pseudoneglect measure. The results showed an increase in perceptual predominance of the rivalry targets differing from the surround across all high-contrast conditions (irrespective of the ambiguity of the context), whereas the effect in the low-contrast condition was less pronounced. We found no laterality effects, but the strength of the context effects scaled with the context size (half/full). In an exploratory analysis, we further found a nasal advantage in the half-field condition. We interpret the results in the theoretical frameworks of surround inhibition and facilitation, figure-ground segregation, pseudoneglect, and nasal visual field advantage.

In the Boynton Illusion, the perceived location of a low-contrast chromatic edge is altered by a nearby high-contrast luminance contour. Our study explores this color spreading effect across different chromatic directions using a position judgment task. We used the gap effect stimulus, which consists of a box evenly divided by a central contour, in half of the conditions. The suprathreshold chromatic test area embedded in the box provided a horizontal chromatic edge parallel to the central, high-contrast luminance contour that varied in its distance from the contour. An attraction effect of the nearest high-contrast contour on low-contrast chromatic and achromatic edges was observed. Specifically, when the test area is smaller than the region defined by the outer and middle contours, the edge is perceived to be closer to the middle contour (the colored area is perceived to be larger), a filling-in effect; conversely, when the test area extends beyond the middle contour, the edge is perceived to be closer to the middle contour (the colored area is perceived to be smaller), indicating a filling-out of color. Achromatic directions exhibit a relatively smaller effect than chromatic directions, whereas S-cone and equiluminant red and green edges show the same magnitude of positional displacement. The results can be interpreted as the visual system attempting to assign a single hue or brightness to a demarcated region.

Virtual reality (VR) can be used to design and create new types of psychophysical experiments. Its main advantage is that it frees us from the physical limitations of real-life experiments and the hardware and software limitations of experiments running on two-dimensional (2D) displays and computer graphics. However, color calibration of the displays is often required in vision science studies. Recent studies have shown that a standard color calibration of a head-mounted display (HMD) can be very challenging and comes with significant drawbacks. These drawbacks include the need to completely disable tone mapping or to use unlit materials when tone mapping is only partially disabled. In this article, we introduce a new approach that allows for successful color calibration of an HMD and overcomes the disadvantages associated with other solutions. We utilize a new VR engine, Three.js, which offers several advantages. This article details our setup and methodology and provides all the elements required to reproduce the method, including the source code. We also apply our method to evaluate and compare three different HMDs: HTC Vive Pro Eye, Meta Quest Pro, and Meta Quest 3. The results show that the HTC Vive Pro Eye performs excellently, the Meta Quest Pro performs well, and the Meta Quest 3 performs poorly.