Emotional content affects the fidelity of visual working memory recall

Context affects psychophysical judgements. Experiments are described that examine central tendency and repetition effects using a standard temporal reproduction task. The range (1–5.5 s), spacing (0.5), and total number of trials (120) were kept constant while the central tendency was manipulated. Flat, skewed long, skewed short, and V-shaped distributions were examined for intervals filled either by unvarying visual or auditory stimuli. Central tendency effects were observed in the skewed distributions and were similar for visual and auditory stimuli. A repetition effect was observed in which reproduced durations increased across trials. This effect has previously been attributed to an arousal decrement but this explanation fails on a reproduction task since an arousal decrement should affect timing of the standard and reproduction equally. Central tendency assimilation might account for the repetition effect if an initial indifference point is below the range of the tested series. Neither repetition nor central tendency effects could explain the results of the V distribution.

Decision letter: The entorhinal-DG/CA3 pathway in the medial temporal lobe retains visual working memory of a simple surface feature

Editor's evaluation: The entorhinal-DG/CA3 pathway in the medial temporal lobe retains visual working memory of a simple surface feature

The relationship between working memory and time perception has been typically investigated using dual-task paradigms (e.g., testing timing performance during a concurrent task). To our knowledge, none of these studies used time intervals as the target stimulus to be remembered. The current study investigated the working memory for time intervals by asking participants to reproduce durations they experienced at different orders in a series of experienced intervals (n-back task). One of the experiments was conducted online and the other one in the lab setting. Results showed a central tendency bias and additive elongation of time reproductions with increasing working memory load. Our results also showed that participants assigned different weights to experienced intervals based on their order of presentation (higher weight to the target interval). We conclude that the recall of intervals from working memory under high cognitive load leads to a central tendency effect, which is known to be induced by the temporal context and present particularly in aging and in those with Parkinson's disease.

Investigating the impact of in-vehicle warning information complexity on drivers: The role of working memory capacity and cognitive load.

Perception is shaped by both the physical properties of stimuli and their contextual presentation, often leading to systematic biases such as the central tendency effect, where perceptual judgments shift toward the average of the stimulus set. This study explored the central tendency bias in vibrotactile perception, an area that has received limited attention while also replicating its well-documented occurrence in color perception to validate previous findings. Using a within-subject design, participants (5 males, 15 females) completed color and vibrotactile discrimination tasks, each consisting of three blocks, which comprised systematically shifted stimulus sets. In an established virtual reality color task, stimuli ranged from yellow–green to blue–green, while in the vibrotactile task, stimuli varied in vibration intensity around a baseline distribution. As predicted, the point of subjective equality shifted toward the mean of the stimulus sets in both tasks, confirming the presence of a central tendency bias. These findings demonstrate that perception of both color and vibrotactile intensity is not determined solely based on the physical properties of the stimulus per se, but it is rather influenced by the distribution of the presented stimuli, underscoring the pervasive role of contextual factors in shaping sensory judgments.

Previous work demonstrates that memory for simple stimuli can be biased by information about the distribution of which the stimulus is a member. Specifically, people underestimate values greater than the distribution's average and overestimate values smaller than the average. This is referred to as the central tendency bias. This bias has been explained as an optimal use of both noisy sensory information and category information. In largely separate literature, cognitive load (CL) experiments attempt to manipulate the available working memory of participants in order to observe the effect on choice or judgments. In two experiments, we demonstrate that participants under high cognitive load exhibit a stronger central tendency bias than when under a low cognitive load. Although not anticipated at the outset, we also find that judgments exhibit an anchoring bias not described previously.

The central tendency bias, or contraction bias, is a phenomenon where the judgment of the magnitude of items held in working memory appears to be biased toward the average of past observations. It is assumed to be an optimal strategy by the brain and commonly thought of as an expression of the brain’s ability to learn the statistical structure of sensory input. On the other hand, recency biases such as serial dependence are also commonly observed and are thought to reflect the content of working memory. Recent results from an auditory delayed comparison task in rats suggest that both biases may be more related than previously thought: when the posterior parietal cortex (PPC) was silenced, both short-term and contraction biases were reduced. By proposing a model of the circuit that may be involved in generating the behavior, we show that a volatile working memory content susceptible to shifting to the past sensory experience – producing short-term sensory history biases – naturally leads to contraction bias. The errors, occurring at the level of individual trials, are sampled from the full distribution of the stimuli and are not due to a gradual shift of the memory toward the sensory distribution’s mean. Our results are consistent with a broad set of behavioral findings and provide predictions of performance across different stimulus distributions and timings, delay intervals, as well as neuronal dynamics in putative working memory areas. Finally, we validate our model by performing a set of human psychophysics experiments of an auditory parametric working memory task.

The central tendency bias, or contraction bias, is a phenomenon where the judgment of the magnitude of items held in working memory appears to be biased toward the average of past observations. It is assumed to be an optimal strategy by the brain and commonly thought of as an expression of the brain's ability to learn the statistical structure of sensory input. On the other hand, recency biases such as serial dependence are also commonly observed and are thought to reflect the content of working memory. Recent results from an auditory delayed comparison task in rats suggest that both biases may be more related than previously thought: when the posterior parietal cortex (PPC) was silenced, both short-term and contraction biases were reduced. By proposing a model of the circuit that may be involved in generating the behavior, we show that a volatile working memory content susceptible to shifting to the past sensory experience - producing short-term sensory history biases - naturally leads to contraction bias. The errors, occurring at the level of individual trials, are sampled from the full distribution of the stimuli and are not due to a gradual shift of the memory toward the sensory distribution's mean. Our results are consistent with a broad set of behavioral findings and provide predictions of performance across different stimulus distributions and timings, delay intervals, as well as neuronal dynamics in putative working memory areas. Finally, we validate our model by performing a set of human psychophysics experiments of an auditory parametric working memory task.

Memories of objects are biased toward what is typical of the category to which they belong. Prior research on memory for emotional facial expressions has demonstrated a bias towards an emotional expression prototype (e.g., slightly happy faces are remembered as happier). We investigate an alternate source of bias in memory for emotional expressions - the central tendency bias. The central tendency bias skews reconstruction of a memory trace towards the center of the distribution for a particular attribute. This bias has been attributed to a Bayesian combination of an imprecise memory for a particular object with prior information about its category. Until now, studies examining the central tendency bias have focused on simple stimuli. We extend this work to socially relevant, complex, emotional facial expressions. We morphed facial expressions on a continuum from sad to happy. Different ranges of emotion were used in four experiments in which participants viewed individual expressions and, after a variable delay, reproduced each face by adjusting a morph to match it. Estimates were biased toward the center of the presented stimulus range, and the bias increased at longer memory delays, consistent with the Bayesian prediction that as trace memory loses precision, category knowledge is given more weight. The central tendency effect persisted within and across emotion categories (sad, neutral, and happy). This article expands the scope of work oninductive category effects to memory for complex, emotional stimuli.

Mental workload evaluation using weighted phase lag index and coherence features extracted from EEG data

Applying the Science of Learning to Classroom Teaching: The Critical Importance of Aligning Learning with Testing

The combination of data visualization and auditory display (e.g., sonification) has been shown to increase accuracy, and reduce perceived difficulty, within 3D navigation tasks. While accuracy within such tasks can be measured in real time, subjective impressions about the difficulty of a task are more elusive to obtain. Prior work utilizing electrophysiology (EEG) has found robust support that cognitive load and working memory can be monitored in real time using EEG data. In this study, we replicated a 3D navigation task (within the context of image-guided surgery) while recording data pertaining to participants' cognitive load through the use of EEG relative alpha-band weighting data. Specifically, 13 subjects navigated a tracked surgical tool to randomly placed 3D virtual locations on a CT cerebral angiography volume while being aided by visual, aural, or both visual and aural feedback. During the study EEG data were captured from the participants, and after the study a NASA TLX questionnaire was filled out by the subjects. In addition to replicating an existing experimental design on auditory display within image-guided neurosurgery, our primary aim sought to determine whether EEG-based markers of cognitive load mirrored subjective ratings of task difficulty RESULTS : Similar to existing literature, our study found evidence consistent with the hypothesis that auditory display can increase the accuracy of navigating to a specified target. We also found significant differences in cognitive working load across different feedback modalities, but none of which supported the experiments hypotheses. Finally, we found mixed results regarding the relationship between real-time measurements of cognitive workload and a posteriori subjective impressions of task difficulty. Although we did not find a significant correlation between the subjective and physiological measurements, differences in cognitive working load were found. As well, our study further supports the use of auditory display in image-guided surgery.

The successful communication of spatial information with maps allows correct spatial memory retrieval. Space-referencing map elements like grid pattern lead to a higher spatial accuracy in memory performance. We studied the influence of the landmark attraction effect and the central tendency bias predicted by the categorical adjustment model. While landmark attraction effect would lead to an attraction toward the landmark for the recalled object location, central tendency bias would lead to a deviation toward the center of a given field. The effects of these distortions were investigated on two different kinds of grid pattern, continuous grid lines and grid crosses, superimposed on a map or on a blank background. Results showed higher object-location memory accuracy for grid crosses. As expected, a clear central tendency bias was observed for the continuous grid lines according to the expected central tendency bias. However, there was no clear landmark attraction effect or central tendency bias for the grid crosses. We suspect a partial cancellation of the two opposing effects in this case. Overall results, central tendency bias seems to be stronger than the landmark attraction effect. In our experimental design, the landmark attraction effect seems not to be able to eliminate the central tendency bias, but to mitigate its strength. We suggest a correcting influence of map elements on object-location memory as the spatial distortions caused by the central tendency bias of the complete grid are significantly reduced in the grid cross condition. Future studies have to show more exactly how different shifting effects of recalled object positions can be used cartographically to reduce distortions of the mental representation of space.

BackgroundComplex motor tasks in immersive virtual reality using a head-mounted display (HMD-VR) have been shown to increase cognitive load and decrease motor performance compared to conventional computer screens (CS). Separately, visuomotor adaptation in HMD-VR has been shown to recruit more explicit, cognitive strategies, resulting in decreased implicit mechanisms thought to contribute to motor memory formation. However, it is unclear whether visuomotor adaptation in HMD-VR increases cognitive load and whether cognitive load is related to explicit mechanisms and long-term motor memory formation.MethodsWe randomized 36 healthy participants into three equal groups. All groups completed an established visuomotor adaptation task measuring explicit and implicit mechanisms, combined with a dual-task probe measuring cognitive load. Then, all groups returned after 24-h to measure retention of the overall adaptation. One group completed both training and retention tasks in CS (measuring long-term retention in a CS environment), one group completed both training and retention tasks in HMD-VR (measuring long-term retention in an HMD-VR environment), and one group completed the training task in HMD-VR and the retention task in CS (measuring context transfer from an HMD-VR environment). A Generalized Linear Mixed-Effect Model (GLMM) was used to compare cognitive load between CS and HMD-VR during visuomotor adaptation, t-tests were used to compare overall adaptation and explicit and implicit mechanisms between CS and HMD-VR training environments, and ANOVAs were used to compare group differences in long-term retention and context transfer.ResultsCognitive load was found to be greater in HMD-VR than in CS. This increased cognitive load was related to decreased use of explicit, cognitive mechanisms early in adaptation. Moreover, increased cognitive load was also related to decreased long-term motor memory formation. Finally, training in HMD-VR resulted in decreased long-term retention and context transfer.ConclusionsOur findings show that cognitive load increases in HMD-VR and relates to explicit learning and long-term motor memory formation during motor learning. Future studies should examine what factors cause increased cognitive load in HMD-VR motor learning and whether this impacts HMD-VR training and long-term retention in clinical populations.