Saturation and brightness modulate the effect of depth on visual working memory

Unraveling the relationship between audience engagement and audiovisual characteristics of automotive green advertising on Chinese TikTok (Douyin)

As video platforms such as Douyin, also known as TikTok's Chinese version, continue to grow, there is an increasing interest in the study of green advertising videos to understand their audiovisual features and their impact on audience engagement. In this research, we specifically focus on green advertising within the automotive industry. Drawing on literature from sustainability, green advertising, and communication studies, we identified seven audiovisual aspects and three persuasive strategies pertinent to green automotive advertising videos. Utilizing a mixed-methods video analysis framework, we analyzed a dataset of 2,553 green automotive advertising videos on Douyin over three years from 15 June 2020 to 15 June 2023. These videos exhibited higher loudness, a faster pace, and longer durations compared to their non-green counterparts. We categorized three distinct types of green advertising videos on Douyin and established that specific audiovisual features and persuasive strategies are significantly correlated with audience engagement levels. This study not only delineates the audiovisual characteristics of green automotive advertising in China's digital space but also contributes to the broader discourse on sustainable marketing practices on social networks like TikTok. The findings extend image-centric research to video content and provide marketers with data-driven insights for crafting effective content creation strategies on Douyin.

The influence of depth on object selection and manipulation in visual working memory within a 3D context

Recent studies have examined whether the internal selection mechanism functions similarly for perception and visual working memory (VWM). However, the process of how we access and manipulate object representations distributed in a 3D space remains unclear. In this study, we utilized a memory search task to investigate the effect of depth on object selection and manipulation within VWM. The memory display consisted of colored items half positioned at the near depth plane and the other half at the far plane. During memory maintenance, the participants were instructed to search for a target representation and update its color. The results showed that under object-based attention (Experiments 1, 3, and 5), the update time was faster for targets at the near plane than for those at the far plane. This effect was absent in VWM when deploying spatial attention (Experiment 2) and in visual search regardless of the type of attention deployed (Experiment 4). The differential effects of depth on spatial and object-based attention in VWM suggest that spatial attention primarily relied on 2D location information irrespective of depth, whereas object-based attention seemed to prioritize memory representations at the front plane before shifting to the back. Our findings shed light on the interaction between depth perception and the selection mechanisms within VWM in a 3D context, emphasizing the importance of ordinal, rather than metric, spatial information in guiding object-based attention in VWM.

Spatial attention based on 2D location and relative depth order modulates visual working memory in a 3D environment

The attentional effect on visual working memory (VWM) has been a heated research topic in the past two decades. Studies show that VWM performance for an attended memory item can be improved by cueing its two-dimensional (2D) spatial location during retention. However, few studies have investigated the effect of attentional selection on VWM in a three-dimensional setting, and it remains unknown whether depth information can produce beneficial attentional effects on 2D visual representations similar to 2D spatial information. Here we conducted four experiments, displaying memory items at various stereoscopic depth planes, and examined the retro-cue effects of four types of cues - a cue would either indicate the 2D or depth location of a memory item, and either in the form of physical (directly pointing to a location) or symbolic (numerically mapping onto a location) cues. We found that retro-cue benefits were only observed for cues directly pointing to a 2D location, whereas a null effect was observed for cues directly pointing to a depth location. However, there was a retro-cue effect when cueing the relative depth order, though the effect was weaker than that for cueing the 2D location. The selective effect on VWM based on 2D spatial attention is different from depth-based attention, and the divergence suggests that an object representation is primarily bound with its 2D spatial location, weakly bound with its depth order but not with its metric depth location. This indicates that attentional selection based on memory for depth, particularly metric depth, is ineffective.

The Short-Term Retention of Depth

We review research on the visual working memory for information portrayed by items arranged in depth (i.e., distance to the observer) within peri-personal space. Most items lose their metric depths within half a second, even though their identities and spatial positions are retained. The paradoxical loss of depth information may arise because visual working memory retains the depth of a single object for the purpose of actions such as pointing or grasping which usually apply to only one thing at a time.

Increasing perceptual separateness affects working memory for depth - re-allocation of attention from boundaries to the fixated center

For decades, working memory (WM) has been a heated research topic in the field of cognitive psychology. However, most studies on WM presented visual stimuli on a two-dimensional plane, rarely involving depth perception. Several previous studies have investigated how depth information is stored in WM, and found that WM for depth is even more limited in capacity and the memory performance is poor compared to visual WM. In the present study, we used a change detection task to investigate whether dissociating memory items by different visual features, thereby to increase their perceptual separateness, can improve WM performance for depth. Memory items presented at various depth planes were bound with different colors (Experiments 1 and 3) or sizes (Experiment 2). The memory performance for depth locations of visual stimuli with homogeneous and heterogeneous appearances were tested and compared. The results showed a consistent pattern that although separating items with various feature values did not affect the overall memory performance, the manipulation significantly improved memory performance for the middle depth locations but impaired the performance for the boundary locations when observers fixated at the center of the whole depth volume. The memory benefits of feature separation can be attributed to enhanced individuation of memory items, therefore facilitating a more balanced allocation of attention and memory resources.

Visual Search in 3D: Effects of Monoscopic and Stereoscopic Cues to Depth on the Validity of Feature Integration Theory and Perceptual Load Theory

Previous research has successfully used feature integration theory to operationalise the predictions of Perceptual Load Theory, while simultaneously testing the predictions of both models. Building on this work, we test the extent to which these models hold up in a 3D world. In two experiments, participants responded to a target stimulus within an array of shapes whose apparent depth was manipulated using a combination of monoscopic and stereoscopic cues. The search task was designed to test the predictions of (a) feature integration theory, as the target was identified by a single feature or a conjunction of features and embedded in search arrays of varying size, and (b) perceptual load theory, as the task included congruent and incongruent distractors presented alongside search tasks imposing high or low perceptual load. Findings from both experiments upheld the predictions of feature integration theory, regardless of 2D/3D condition. Longer search times in conditions with a combination of monoscopic and stereoscopic depth cues suggests that binding features into three-dimensional objects requires greater attentional effort. This additional effort should have implications for perceptual load theory, yet our findings did not uphold its predictions; the effect of incongruent distractors did not differ between conjunction search trials (conceptualised as high perceptual load) and feature search trials (low perceptual load). Individual differences in susceptibility to the effects of perceptual load were evident and likely explain the absence of load effects. Overall, our findings suggest that feature integration theory may be useful for predicting attentional performance in a 3D world.

Size-distance rescaling in the ensemble representation of range: Study with binocular and monocular cues

According to numerous studies observers can rapidly and precisely evaluate mean or range of the set. Recent studies have shown that the mean size estimated based on sizes of objects rescaled to their distances (Tiurina & Utochkin, 2019). In the current study, we directly tested this rescaling mechanism on the perception of range using binocular and monocular cues. In Experiment 1, a sample set of circles with different angular sizes and in different apparent distances were stereoscopically presented. Participants had to adjust the range of the test set to match the range of the sample set. The main manipulation was the size-distance correlation for sample and test sets: in negative size-distance correlation, the apparent range had to decrease, while in positive correlation - increase. We found the highest underestimation in the condition with the negative sample correlation and positive test correlation, which could be explained only if ensemble summary statistics were estimated after the item's rescaling. In Experiment 2, we used Ponzo-like illusion and spatial positions as a depth cue. Sets were presented with positive, negative or without size-distance correlation on a grey background or the background with Ponzo-like illusion. We found that the range was underestimated in negative correlation and overestimated in positive correlation. Thus, items of ensemble could be automatically rescaled according to their distance, based on both binocular and monocular cues, and ensemble summary statistics estimation is based on perceived sizes.

Optical pavement treatments and their impact on speed and lateral position at transition zones: A driving simulator study

Transition zones are a road section where posted speed drops from higher to lower limits. Due to the sudden changes in posted speed limits and road environment, drivers usually do not adapt to the posted speed limits and underestimate their traveling speed. Previous studies have highlighted that crash rates are usually higher in these sections. This study aims at improving the safety at transition zones by introducing perceptual measures that are tested using a driving simulator. The proposed measures are speed limit pavement markings with a gradual increase of brightness and/or size that were placed at transition zones in simulation scenarios replicating the real-world environment of the Doha Expressway in Qatar. These innovative measures aim to produce the impression of increased speed that could stimulate drivers to better adapt speed limits. The driving behavior of 81 drivers possessing a valid Qatari driving license was recorded with a driving simulator interfaced with STISIM Drive® 3. Results showed that pavement markings combining size and brightness manipulations were the most effective treatment, keeping drivers' traveling speed significantly below the traveling speed recorded in the untreated control condition. In this regard, the maximum mean speed reductions of 5.3 km/h and 4.6 km/h were observed for this treatment at the first transition (120 to 100 km/h) and second transition (100 to 80 km/h) zones, respectively. Regarding the variations in drivers' lateral position, the results showed that the proposed pavement markings did not negatively influence drivers' lateral control on the road as the maximum observed standard deviation of lateral position was around 0.065 m. This study shows that the proposed pavement markings are recommended for improving the speed adaptation of drivers in the transition zones.

Effect of attentional selection on working memory for depth in a retro-cueing paradigm

Recent studies have shown that the temporary storage and manipulation of depth information (working memory for depth; WMd) is largely different from that of visual information in a 2D context (visual working memory; VWM). Although there has been abundant evidence on VWM showing that cueing a memory item during retention could bias attention to its internal representation and thus improves its memory performance (a retro-cue effect), it is unknown whether such an effect differs for WMd that is nested in a 3D context compared with that in a conventional 2D context. Here, we used a change detection task to investigate the effect of attentional selection on WMd by testing several types of retro-cue. The memory array consisted of items positioned at various stereoscopic depth planes, and a cue was presented during retention. Participants needed to make judgments on whether the depth position of target (one memory item) had changed. Our study showed reliable valid retro-cue benefits but no invalid retro-cue cost, indicating that the relational information may be registered in WMd to prevent a strategical removal of the unattended item. There was also a slight improvement in memory performance for cueing depth order compared with that for cueing other feature dimensions or 2D locations. The attentional effect on memory representation in a 3D context is different from that in a 2D context, and the divergence may suggest the distinctive nature of working memory for depth.

Relation matters: relative depth order is stored in working memory for depth

Working memory is considered as a cognitive memory buffer for temporarily holding, processing, and manipulating information. Although working memory for verbal and visual information has been studied extensively in the past literature, few studies have systematically investigated how depth information is stored in working memory. Here, we show that the memory performance for detecting changes in stereoscopic depth is low when there is no change in relative depth order, and the performance is reliably better when depth order is changed. Increasing the magnitude of change only improves memory performance when depth order is kept constant. However, if depth order is changed, the performance remains high, even with a small change magnitude. Our findings suggest that relative depth order is a better indicator for working memory performance than absolute metric depth. The memory representation for individual depth is not independent, but inherently relational, revealing a fundamental organizing principle for depth information in the visual system.

Training with high perceptual difficulty improves the capacity and fidelity of internal representation in VWM

It has been shown that the capacity of visual working memory (VWM) is a strong predictor of individual intelligence, and researchers have developed various training protocols to improve VWM capacity. However, it seems that whether the fidelity of internal representation in VWM can also be improved by training is largely overlooked in the past literature. Here, we introduced a new training approach that involved increasing the perceptual difficulty of training materials to enhance VWM, and both memory capacity and the fidelity of representation were examined to assess the training efficacy. Participants with normal vision and cognitive abilities received 3-week training on VWM using a change detection task, and the results showed that both the capacity and the fidelity of memory representations were improved for training with perceptually difficult stimuli, while only the fidelity was improved for training with perceptually normal stimuli. In addition, we found that the training effects on memory precision may be subject to capacity constraints. We suggest that long-term adaptive training with perceptually difficult stimuli may facilitate encoding efficiency through familiarizing trainees with an increased baseline of cognitive workload during the encoding process. The present study offers clear evidence that training with high perceptual difficulty is more effective and the improvements in VWM are more stable than training with perceptually normal materials, and the simple manipulation on training stimuli indicates that the method can be generalized to a wider range of training situations and populations.

Exogenous spatial attention shortens perceived depth

Although spatial attention has been found to alter the subjective appearance of visual stimuli in several perceptual dimensions, no research has explored whether exogenous spatial attention can affect depth perception, which is a fundamental dimension in perception that allows us to effectively interact with the environment. Here, we used an experimental paradigm adapted from Gobell and Carrasco (Psychological Science, 16[8], 644-651, 2005) to investigate this question. A peripheral cue preceding two line stimuli was used to direct exogenous attention to either location of the two lines. The two lines were separated by a certain relative disparity, and participants were asked to judge the perceived depth of two lines while attention was manipulated. We found that a farther stereoscopic depth at the attended location was perceived to be equally distant as a nearer depth at the unattended location. No such effect was found in a control experiment that employed a postcue paradigm, suggesting that our findings could not be attributed to response bias. Therefore, our study shows that exogenous spatial attention shortens perceived depth. The apparent change in stereoscopic depth may be regulated by a mechanism involving direct neural enhancement on those tuned to disparity, or be modulated by an attentional effect on apparent contrast. This finding shows that attention can change not only visual appearance but also the perceived spatial relation between an object and an observer.

Working memory for stereoscopic depth is limited and imprecise-evidence from a change detection task

Most studies on visual working memory (VWM) and spatial working memory (SWM) have employed visual stimuli presented at the fronto-parallel plane and few have involved depth perception. VWM is often considered as a memory buffer for temporarily holding and manipulating visual information that relates to visual features of an object, and SWM for holding and manipulating spatial information that concerns the spatial location of an object. Although previous research has investigated the effect of stereoscopic depth on VWM, the question of how depth positions are stored in working memory has not been systematically investigated, leaving gaps in the existing literature on working memory. Here, we explore working memory for depth by using a change detection task. The memory items were presented at various stereoscopic depth planes perpendicular to the line of sight, with one item per depth plane. Participants were asked to make judgments on whether the depth position of the target (one of the memory items) had changed. The results showed a conservative response bias that observers tended to make 'no change' responses when detecting changes in depth. In addition, we found that similar to VWM, the change detection accuracy degraded with the number of memory items presented, but the accuracy was much lower than that reported for VWM, suggesting that the storage for depth information is severely limited and less precise than that for visual information. The detection sensitivity was higher for the nearest and farthest depths and was better when the probe was presented along with the other items originally in the memory array, indicating that how well the to-be-stored depth can be stored in working memory depends on its relation with the other depth positions.

Task-dependent effects of voluntary space-based and involuntary feature-based attention on visual working memory

Previous research has shown that visual working memory (VWM) can be modulated by space-based or feature-based attentional selection. However, it remains unclear how the two modes of attention operate jointly to affect VWM, and in particular, if involuntary feature-based attention plays a role in VWM. In this study, a pre-cued change detection paradigm was employed to investigate the concurrent effects of space- and feature-based attention on VWM. Space-based attention was manipulated by informative spatial cueing and by varying the proximity between the test item and the cued (fixated) memory item, while feature-based attention was induced in an involuntary manner by having the test item to share the same color or shape with the cued item on a fraction of trials. The results showed that: (1) the memory performance for the cued items was always better than the uncued items, suggesting a beneficial effect of voluntary spatial attention; (2) with a brief duration of the memory array (250 ms), cue-test proximity benefited VWM in the shape judgment task but not in the color judgment task, whereas with a longer duration (1200 ms), no proximity effect was found for either task; (3) VWM was improved for the same-colored items regardless of the task and duration; (4) VWM was improved for the same-shaped items only in the shape judgment task with the longer duration of the memory array. A discrimination task further showed that the proximity effect associated with VWM reflects a perceptual bottleneck in memory encoding for shape but not for color with a brief display. Our results suggest that involuntary feature-based attention could be triggered by spatial cueing to modulate VWM; involuntary color-based attention facilitates VWM independently of task, whereas shape-based facilitation is task-dependent, i.e., confined only to the shape judgment task, presumably reflecting different attention-guiding potencies of the two features.

Evidence for the beneficial effect of perceptual grouping on visual working memory: an empirical study on illusory contour and a meta-analytic study

The capacity of visual working memory (VWM) is found to be extremely limited. Past research shows that VWM can be facilitated by Gestalt principles of grouping, however, it remains controversial whether factors like the type of Gestalt principles, the characteristics of stimuli and the nature of experimental design could affect the beneficial effect of grouping. In particular, studies have shown that perceptual grouping could improve memory performance for a feature that is relevant for grouping, but it is unclear whether the same improvement exists for a feature that is irrelevant for grouping. In this article, an empirical study and a meta-analytic study were conducted to investigate the effect of perceptual grouping on VWM. In the empirical study, we examined the grouping effect by employing a Kanizsa illusion in which memory items were grouped by illusory contour. We found that the memory performance was improved for the grouped items even though the tested feature was grouping irrelevant, and the improvement was not significantly different from the effect of grouping by physical connectedness or by solid occlusion. In the meta-analytic study, we systematically and quantitatively examined the effect of perceptual grouping on VWM by pulling the results from all eligible studies, and found that the beneficial grouping effect was robust but the magnitude of the effect can be affected by several moderators. Factors like the types of grouping methods, the duration and the layout of the memory display, and the characteristics of the tested feature moderated the grouping effect, whereas whether employing a cue or a verbal suppression task did not. Our study suggests that the underlying mechanism of the grouping benefit may be distinct with regard to grouping relevancy of the to-be-stored feature. The grouping effect on VWM may be independent of attention for a grouping relevant feature, but may rely on attentional prioritization for a grouping irrelevant feature.

Effects of Color and Luminance Contrast on Size Perception-Evidence from a Horizontal Parallel Lines Illusion

The present study investigated a size illusion composed of two horizontal lines that were vertically separated and parallel to each other. When the two lines were of equal length, the upper line was consistently perceived to be a little longer than the lower line, therefore it was termed as horizontal parallel lines (HPL) illusion. We investigated the effect of color and luminance contrast on the HPL illusion by manipulating the color and luminance of the two lines. Results indicated the following: (1) differences in color between the two lines reduced the illusion; (2) differences in luminance between the two lines reduced the illusion; (3) Effect 1 was greater than Effect 2; (4) the illusory effect could not be affected as long as both of the lines were of the same color or luminance. The results suggest that the color or luminance contrast may contribute to the overall decrease in the illusory effect for lines with different colors/luminances, but generally the illusion decreases as the two lines are less similar to each other. These findings indicate that the similarity or ‘sameness’ effect dominates the effect of color/luminance contrast on the size illusion over the effect resulted from contrast difference or depth perception.