The influence of tDCS on perceived bouncing/streaming.

Processing ambiguous situations is a constant challenge in everyday life and sensory input from different modalities needs to be integrated to form a coherent mental representation on the environment. The bouncing/streaming illusion can be studied to provide insights into the ambiguous perception and processing of multi-modal environments. In short, the likelihood of reporting bouncing rather than streaming impressions increases when a sound coincides with the moment of overlap between two moving disks. Neuroimaging studies revealed that the right posterior parietal cortex is crucial in cross-modal integration and is active during the bouncing/streaming illusion. Consequently, in the present study, we used transcranial direct current stimulation to stimulate this brain area. In the active stimulation conditions, a 9 cm2 electrode was positioned over the P4-EEG position and the 35 cm2 reference positioned over the left upper arm. The stimulation lasted 15 min. Each participant did the bouncing/streaming task three times: before, during and after anodal or sham stimulation. In a sample of N = 60 healthy, young adults, we found no influence of anodal tDCS. Bayesian analysis showed strong evidence against tDCS effects. There are two possible explanations for the finding that anodal tDCS over perceptual areas did not modulate multimodal integration. First, upregulation of multimodal integration is not possible using tDCS over the PPC as the integration process already functions at maximum capacity. Second, prefrontal decision-making areas may have overruled any modulated input from the PPC as it may not have matched their decision-making criterion and compensated for the modulation.

Long-term memory representations for audio-visual scenes.

In this study, we investigated the nature of long-term memory representations for naturalistic audio-visual scenes. Whereas previous research has shown that audio-visual scenes are recognized more accurately than their unimodal counterparts, it remains unclear whether this benefit stems from audio-visually integrated long-term memory representations or a summation of independent retrieval cues. We tested two predictions for audio-visually integrated memory representations. First, we used a modeling approach to test whether recognition performance for audio-visual scenes is more accurate than would be expected from independent retrieval cues. This analysis shows that audio-visual integration is not necessary to explain the benefit of audio-visual scenes relative to purely auditory or purely visual scenes. Second, we report a series of experiments investigating the occurrence of study-test congruency effects for unimodal and audio-visual scenes. Most importantly, visually encoded information was immune to additional auditory information presented during testing, whereas auditory encoded information was susceptible to additional visual information presented during testing. This renders a true integration of visual and auditory information in long-term memory representations unlikely. In sum, our results instead provide evidence for visual dominance in long-term memory. Whereas associative auditory information is capable of enhancing memory performance, the long-term memory representations appear to be primarily visual.

Symmetry and spatial ability enhance change detection in visuospatial structures.

Science, Technology, Engineering, and Mathematics (STEM) domains require people to recognize and transform complex visuospatial displays that appear to vastly exceed the limits of visuospatial working memory. Here, we consider possible domain-general mechanisms that may explain this advantage: capitalizing on symmetry, a structural regularity that can produce more efficient representations. Participants briefly viewed a structure made up of three-dimensional connected cubes of different colors, which was either asymmetrical or symmetrical. After a short delay, they were asked to detect a change (colors swapping positions) within a rotated second view. In change trials, the second display always had an asymmetrical structure. The presence of symmetry in the initial view improved change detection, and performance also declined with angular disparity of the encoding and test displays. People with higher spatial ability performed better on the change-detection task, but there was no evidence that they were better at leveraging symmetry than low-spatial individuals. The results suggest that leveraging symmetrical structures can help people of all ability levels exceed typical working memory limits by constructing more efficient representations and substituting resource-demanding mental rotation operations with alternative orientation-independent strategies.

Medical education videos as a tool for rehearsal: efficiency and the cases of background music and difficulty.

This study reports a field experiment investigating how instructional videos with and without background music contribute to the learning of examination techniques within a formal curriculum of medical teaching. Following a classroom teaching unit on the techniques for examining the knee and the shoulder joint, our participants (N = 175) rehearsed the studied techniques for either the knee or the shoulder joint with an instructional video with or without background music. As dependent measures, we collected a general questionnaire, a prediction of test performance, as well as performance on an exam-like knowledge test covering both joints. For both videos, the participants who had watched the particular video during rehearsal were more accurate in answering the corresponding questions than the participants who had seen the other video, signaling that instructional videos provide a useful tool for rehearsal (i.e., both groups reciprocally served as control groups). For the knee video (less difficult), we observed a detrimental effect of the background music, whereas we observed no such effect for the shoulder video (more difficult). Further explorations revealed that background music might be detrimental for learning, as it reduces the perceived demand characteristics. Because the impact of the demand characteristics might be more pronounced in less difficult instructional videos, we discuss video difficulty as a potential moderating factor. Overall, our study provides evidence that instructional videos could be usefully implemented in formal teaching curricula and that such instructional videos probably should be designed without background music.

From metacognitive beliefs to strategy selection: does fake performance feedback influence cognitive offloading?

The ubiquitous availability of technological aids requires individuals to constantly decide between either externalizing cognitive processes into these aids (i.e. cognitive offloading) or relying on their own internal cognitive resources. With the present research, we investigated the influence of metacognitive beliefs on individuals' offloading behavior in an experimental setup (N = 159). We manipulated participants' metacognitive beliefs about their memory abilities by providing fake performance feedback: below-average feedback, above-average feedback, or no feedback (control-group). We then measured offloading behavior, using a pattern copying task in which participants copied a color pattern from a model window into a workspace window. While solving this task, participants could rely either more on an internal memory strategy or more on an offloading strategy. Fake performance feedback affected the participants' metacognitive evaluations about their memory abilities (below-group < control-group < above-group). Although fake performance feedback did not affect actual offloading behavior, the participants receiving below-average performance feedback reported that they had relied more on an offloading strategy than those participants receiving above-average performance feedback. Furthermore, the participants in the below-group reported lower general memory abilities than the other groups at the end of the experiment. We conclude that while fake performance feedback strongly influenced metacognitive beliefs, this did not transfer into a change of strategy selection, thus not influencing offloading behavior. We propose to consider not only metacognitive beliefs but also metacognitive experiences as potential determinants of cognitive offloading.

Mentored undergraduate operating room teaching during the orthopedic trauma curriculum-No evidence of gender differences.

BACKGROUND: In many surgical disciplines, the interest among medical students to pursue a surgical career decreases during their medical studies. The same goes for students after graduation. The aim of our cohort study was to evaluate the operating room (OR) experiences of medical students during our curriculum. MATERIALS AND METHODS: Over the course of one year 217 senior year medical students were included in our study. All of them took part in our training program for senior year medical students, which consisted of a 1-week clinical rotation including visits to the OR. We developed a Likert-scaled questionnaire, which was evaluated anonymously; free text answers were also possible. RESULTS: Prior to the analysis of the sex and age differences, we confirmed that the evaluation scale provided a coherent measure of the OR evaluation. As a first proxy, we conducted a series of Spearman correlations which revealed high intercorrelations between all of the six items of the questionnaire, r(154) = 0.53 to r(154) = 0.94, all p < 0.001. These high intercorrelations transferred into a very high consistency of the six questions that evaluate the OR teaching; Cronbach's α = 0.95. There was no main effect of sex, F (1,146) = 2.19, p = 0.141. However, there was a main effect of age, F (2,146) = 3.75, p = 0.026, indicating that older participants evaluated the OR teaching more positively. Finally, there was no correlation between sex and age group, F (2,146) < 1, indicating that the effect of age on the evaluation score was equally pronounced for female and male participants. DISCUSSION: The aim of this study was to answer the question how mentored OR teaching during the orthopedic trauma curriculum is evaluated by medical students, and whether there are gender-specific differences. For this purpose we prospectively evaluated senior year medical students over a period of 12 months during the orthopedic trauma curriculum with questionnaires. The medical students rated the mentored OR visits mainly positive. CONCLUSION: Previously published literature as well as our presented data indicate that the interest of medical students in starting a surgical career can only be increased if negative influencing factors are reduced. This includes especially positive communication with medical students and in daily professional interaction.

Individual differences in visual attention: A short, reliable, open-source, and multilingual test of multiple object tracking in PsychoPy.

Individual differences in attentional abilities provide an interesting approach in studying visual attention as well as the relation of attention to other psychometric measures. However, recent research has demonstrated that many tasks from experimental research are not suitable for individual differences research, as they fail to capture these differences reliably. Here, we provide a test for individual differences in visual attention which relies on the multiple object tracking task (MOT). This test captures individual differences reliably in 6 to 15 min. Within the task, the participants have to maintain a set of targets (among identical distractors) across an interval of object motion. It captures the efficiency of attentional deployment. Importantly, this test was explicitly designed and tested for reliability under conditions that match those of most laboratory research (restricted sample of students, approximately n = 50). The test is free to use and runs fully under open-source software. In order to facilitate the application of the test, we have translated it into 16 common languages (Chinese, Danish, Dutch, English, Finnish, French, German, Italian, Japanese, Norwegian, Polish, Portuguese, Russian, Spanish, Swedish, and Turkish). The test can be downloaded at https://osf.io/qy6nb/ . We hope that this MOT test supports researchers whose field of study requires capturing individual differences in visual attention reliably.

The contradictory influence of velocity: representational momentum in the tactile modality.

Representational momentum (RM) is the term used to describe a systematic mislocalization of dynamic stimuli, a forward shift; that is, an overestimation of the location of a stimulus along its anticipated trajectory. In the present study, we investigate the effect of velocity on tactile RM, because two distinct and contrasting predictions can be made, based on different theoretical accounts. According to classical accounts of RM, based on numerous visual and auditory RM studies, an increase of the forward shift with increasing target velocity is predicted. In contrast, theoretical accounts explaining spatiotemporal tactile illusions such as the tau or cutaneous rabbit effect predict a decrease of the forward shift with increasing target velocity. In three experiments reported here, a tactile experimental setup modeled on existing RM setups was implemented. Participants indicated the last location of a sequence of three tactile stimuli, which either did or did not imply motion in a consistent direction toward the elbow/wrist. Velocity was manipulated by changing the interstimulus interval as well as the duration of the stimuli. The results reveal that increasing target velocity led to a decrease and even a reversal of the forward shift, resulting in a backward shift. This result is consistent with predictions based on the evidence from tactile spatiotemporal illusions. The theoretical implications of these results for RM are discussed. NEW & NOTEWORTHY This study tests two distinct predictions concerning the influence of velocity on the localization of dynamic tactile stimuli. We demonstrate for tactile stimuli that with increasing velocity, a misperception in the direction of anticipated motion (termed "representational momentum") turns into a misperception against the direction of motion. This result is in line with predictions based on tactile spatiotemporal illusions but challenges classical theoretical accounts of representational momentum based on evidence from vision and audition.

Semantic congruency but not temporal synchrony enhances long-term memory performance for audio-visual scenes.

Human long-term memory for visual objects and scenes is tremendous. Here, we test how auditory information contributes to long-term memory performance for realistic scenes. In a total of six experiments, we manipulated the presentation modality (auditory, visual, audio-visual) as well as semantic congruency and temporal synchrony between auditory and visual information of brief filmic clips. Our results show that audio-visual clips generally elicit more accurate memory performance than unimodal clips. This advantage even increases with congruent visual and auditory information. However, violations of audio-visual synchrony hardly have any influence on memory performance. Memory performance remained intact even with a sequential presentation of auditory and visual information, but finally declined when the matching tracks of one scene were presented separately with intervening tracks during learning. With respect to memory performance, our results therefore show that audio-visual integration is sensitive to semantic congruency but remarkably robust against asymmetries between different modalities.

Gaze coherence reveals distinct tracking strategies in multiple object and multiple identity tracking.

In dynamic environments, a central task of the attentional system is to keep track of objects changing their spatial location over time. In some instances, it is sufficient to track only the spatial locations of moving objects (i.e., multiple object tracking; MOT). In other instances, however, it is also important to maintain distinct identities of moving objects (i.e., multiple identity tracking; MIT). Despite previous research, it is not clear whether MOT and MIT performance emerge from the same tracking mechanism. In the present report, we study gaze coherence (i.e., the extent to which participants repeat their gaze behaviour when tracking the same object locations twice) across repeated MOT and MIT trials. We observed more substantial gaze coherence in repeated MOT trials compared to the repeated MIT trials or mixed MOT-MIT trial pairs. A subsequent simulation study suggests that MOT is based more on a grouping mechanism than MIT, whereas MIT is based more on a target-jumping mechanism than MOT. It thus appears unlikely that MOT and MIT emerge from the same basic tracking mechanism.

Mutual interplay between cognitive offloading and secondary task performance.

Various modern tools, such as smartphones, allow for cognitive offloading (i.e., the externalization of cognitive processes). In this study, we examined the use and consequences of cognitive offloading in demanding situations in which people perform multiple tasks concurrently-mimicking the requirements of daily life. In a preregistered study, we adapted the dual-task paradigm so that one of the tasks allowed for cognitive offloading. As a primary task, our participants (N = 172) performed the pattern copy task-a highly demanding working memory task that allows for offloading at various degrees. In this task, we manipulated the temporal costs of offloading. Concurrently, half of the participants responded to a secondary N-back task. As our main research question, we investigated the impact of offloading behavior on secondary task performance. We observed that more pronounced offloading in the condition without temporal costs was accompanied by a more accurate performance in the N-back task. Furthermore, the necessity to respond to the N-back task increased offloading behavior. These results suggest an interplay between offloading and secondary task performance: in demanding situations, individuals increasingly use cognitive offloading, which releases internal resources that can then be devoted to improving performance in other, concurrent tasks.

The Beep-Speed Illusion Cannot Be Explained With a Simple Selection Bias.

An object appears to move at higher speed than another equally fast object when brief nonspatial tones coincide with its changes in motion direction. We refer to this phenomenon as the beep-speed illusion (Meyerhoff et al., 2022, Cognition, 219, 104978). The origin of this illusion is unclear; however, attentional explanations and potential biases in the response behavior appear to be plausible candidates. In this report, we test a simple bias explanation that emerges from the way the dependent variable is assessed. As the participants have to indicate the faster of the two objects, participants possibly always indicate the audio-visually synchronized object in situations of perceptual uncertainty. Such a response behavior potentially could explain the observed shift in perceived speed. We therefore probed the magnitude of the beep-speed illusion when the participants indicated either the object that appeared to move faster or the object that appeared to move slower. If a simple selection bias would explain the beep-speed illusion, the response pattern should be inverted with the instruction to indicate the slower object. However, contrary to this bias hypothesis, illusion emerged indistinguishably under both instructions. Therefore, simple selection biases cannot explain the beep-speed illusion.

When linguistic uncertainty spreads across pieces of information: Remembering facts on the news as speculation.

Modern media enable rapid reporting that does not refer to facts alone but is often interspersed with unconfirmed speculations. Whereas previous research has concentrated primarily on how unconfirmed contents might propagate, potential memory effects of reporting confirmed facts among speculations have so far been widely disregarded. Across four experiments, we show that the presence of speculative news (indexed by uncertainty cues such as "might") can reduce the remembered certainty of unrelated facts. The participants read headlines with exclusively speculative news, exclusively factual news, or a mixture of both. Our results indicate that uncertainty cues spread onto one's recollection of unrelated facts after having read a mixture of facts and speculations. This tendency persisted when both types of news were presented sequentially (e.g., factual news first), suggesting that the presence of speculative news does not specifically affect encoding-but can overshadow memories of facts in retrospect. Further, the tendency to misremember facts as speculations emerged even when the proportion of speculations among factual news was low (6/24 headlines) but increased linearly with the number of speculations intermingled. Given the widespread dissemination of speculative news, this bias poses a challenge in effectively getting confirmed information across to readers. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

The Impact of Audio-Visual, Visual and Auditory Cues on Multiple Object Tracking Performance in Children with Autism.

Previous studies have documented differences in processing multisensory information by children with autism compared to typically developing children. Furthermore, children with autism have been found to track fewer multiple objects on a screen than those without autism, suggesting reduced attentional control. In the present study, we investigated whether children with autism (n = 33) and children without autism (n = 33) were able to track four target objects moving amongst four indistinguishable distractor objects while sensory cues were presented. During tracking, we presented various types of cues - auditory, visual, or audio-visual or no cues while target objects bounced off the inner boundary of a centralized circle. We found that children with autism tracked fewer targets than children without autism. Furthermore, children without autism showed improved tracking performance in the presence of visual cues, whereas children with autism did not benefit from sensory cues. Whereas multiple object tracking performance improved with increasing age in children without autism, especially when using audio-visual cues, children with autism did not show age-related improvement in tracking. These results are in line with the hypothesis that attention and the ability to integrate sensory cues during tracking are reduced in children with autism. Our findings could contribute valuable insights for designing interventions that incorporate multisensory information.

In case of doubt for the speculation? When people falsely remember facts in the news as being uncertain.

Modern media report news remarkably fast, often before the information is confirmed. This general tendency is even more pronounced in times of an increasing demand for information, such as during pressing natural phenomena or the pandemic spreading of diseases. Yet, even if early reports correctly identify their content as speculative (rather than factual), recipients may not adequately consider the preliminary nature of such information. Theories on language processing suggest that understanding a speculation requires its reconstruction as a factual assertion first-which can later be erroneously remembered. This would lead to a bias to remember and treat speculations as if they were factual, rather than falling for the reverse mistake. In six experiments, however, we demonstrate the opposite pattern. Participants read news headlines with explanations for distinct events either in form of a fact or a speculation (as still being investigated). Both kinds of framings increased participants' belief in the correctness of the respective explanations to an equal extent (relative to receiving no explanation). Importantly, however, this effect was not mainly driven by a neglect of uncertainty cues (as present in speculations). In contrast, our memory experiments (recognition and cued recall) revealed a reverse distortion: a bias to falsely remember and treat a presented "fact" as if it were merely speculative. Based on these surprising results, we outline new theoretical accounts on the processing of (un)certainty cues which incorporate their broader context. Particularly, we propose that facts in the news might be remembered differently once they are presented among speculations. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Context modulates the impact of auditory information on visual anticipation.

Research on the impact of auditory information on visual anticipation in tennis suggests that the intensity of racket-ball-contact sounds systematically biases estimates of the ball's speed, thereby influencing anticipatory judgments. Here we examined whether the effect of auditory information on visual anticipation is dependent on the sport-specific context in two separate experiments. In Exp. 1, participants watched short videos of tennis rallies that were occluded at racket-ball-contact. Racket-ball-contact sounds of the final shot were either present or absent. Participants faced different tasks in two counterbalanced blocks: In one block they estimated the ball's speed; in the other block they indicated the ball's landing location. Results showed that participants estimated longer ball flight trajectories and higher ball speeds in the sound present condition than in the sound absent condition. To probe whether this effect is dependent on the sport-specific context, Exp. 2 introduced an abstract (i.e., context-free) version of the previous stimuli. Based on the ball locations in the original videos used in Exp. 1, we rendered new videos that displayed only a moving circle against a blank background. Sine tones replaced the original racket-ball contact sounds. Results showed no impact of sound presence on location anticipation judgments. However, similar to Exp. 1, object speeds were judged to be faster when the final sound was present. Together, these findings suggest that the impact of auditory information on anticipation does not seem to be driven by sound alone, but to be moderated by contextual information.

The beep-speed illusion: Non-spatial tones increase perceived speed of visual objects in a forced-choice paradigm.

We introduce a new audio-visual illusion revealing the interplay between audio-visual integration and selective visual attention. This illusion involves two simultaneously moving objects that change their motion trajectory occasionally, but only the direction changes of one object are accompanied by spatially uninformative tones. We observed a selective increase in perceived object speed of the audio-visually synchronized object by measuring the point of subjective equality in a forced-choice paradigm. The illusory increase in perceived speed of the audio-visually synchronized object persisted when preventing eye movements. Using temporally matched color changes of the synchronized object also increased the perceived speed. Yet, using color changes of a surrounding frame instead of tones had no effect on perceived speed ruling out simple alertness explanations. Thus, in contrast to coinciding tones, visual coincidences only elicit illusory increases in perceived speed when the coincidence provided spatial information. Taken together, our pattern of results suggests that audio-visual synchrony attracts visual attention toward the coinciding visual object, leading to an increase in speed-perception and thus shedding new light on the interplay between attention and multisensory feature integration. We discuss potential limitations such as the choice of paradigm and outline prospective research question to further investigate the effect of audio-visual integration on perceived object speed.

Exploring the effectiveness of auditory, visual, and audio-visual sensory cues in a multiple object tracking environment.

Maintaining object correspondence among multiple moving objects is an essential task of the perceptual system in many everyday life activities. A substantial body of research has confirmed that observers are able to track multiple target objects amongst identical distractors based only on their spatiotemporal information. However, naturalistic tasks typically involve the integration of information from more than one modality, and there is limited research investigating whether auditory and audio-visual cues improve tracking. In two experiments, we asked participants to track either five target objects or three versus five target objects amongst similarly indistinguishable distractor objects for 14 s. During the tracking interval, the target objects bounced occasionally against the boundary of a centralised orange circle. A visual cue, an auditory cue, neither or both coincided with these collisions. Following the motion interval, the participants were asked to indicate all target objects. Across both experiments and both set sizes, our results indicated that visual and auditory cues increased tracking accuracy although visual cues were more effective than auditory cues. Audio-visual cues, however, did not increase tracking performance beyond the level of purely visual cues for both high and low load conditions. We discuss the theoretical implications of our findings for multiple object tracking as well as for the principles of multisensory integration.

Visual working memory for connected 3D objects: effects of stimulus complexity, dimensionality and connectivity.

Visual working memory (VWM) is typically measured using arrays of two-dimensional isolated stimuli with simple visual identities (e.g., color or shape), and these studies typically find strong capacity limits. Science, technology, engineering and mathematics (STEM) experts are tasked with reasoning with representations of three-dimensional (3D) connected objects, raising questions about whether those stimuli would be subject to the same limits. Here, we use a color change detection task to examine working memory capacity for 3D objects made up of differently colored cubes. Experiment 1a shows that increasing the number of parts of an object leads to less sensitivity to color changes, while change-irrelevant structural dimensionality (the number of dimensions into which parts of the structure extend) does not. Experiment 1b shows that sensitivity to color changes decreases similarly with increased complexity for multipart 3D connected objects and disconnected 2D squares, while sensitivity is slightly higher with 3D objects. Experiments 2a and 2b find that when other stimulus characteristics, such as size and visual angle, are controlled, change-irrelevant dimensionality and connectivity have no effect on performance. These results suggest that detecting color changes on 3D connected objects and on displays of isolated 2D stimuli are subject to similar set size effects and are not affected by dimensionality and connectivity when these properties are change-irrelevant, ruling out one possible explanation for scientists' advantages in storing and manipulating representations of complex 3D objects.

Consequences of cognitive offloading: Boosting performance but diminishing memory.

Modern technical tools such as tablets allow for the temporal externalisation of working memory processes (i.e., cognitive offloading). Although such externalisations support immediate performance on different tasks, little is known about potential long-term consequences of offloading behaviour. In the current set of experiments, we studied the relationship between cognitive offloading and subsequent memory for the offloaded information as well as the interplay of this relationship with the goal to acquire new memory representations. Our participants solved the Pattern Copy Task, in which we manipulated the costs of cognitive offloading and the awareness of a subsequent memory test. In Experiment 1 (N = 172), we showed that increasing the costs for offloading induces reduced offloading behaviour. This reduction in offloading came along with lower immediate task performance but more accurate memory in an unexpected test. In Experiment 2 (N = 172), we confirmed these findings and observed that offloading behaviour remained detrimental for subsequent memory performance when participants were aware of the upcoming memory test. Interestingly, Experiment 3 (N = 172) showed that cognitive offloading is not detrimental for long-term memory formation under all circumstances. Those participants who were forced to offload maximally but were aware of the memory test could almost completely counteract the negative impact of offloading on memory. Our experiments highlight the importance of the explicit goal to acquire new memory representations when relying on technical tools as offloading did have detrimental effects on memory without such a goal.