Change Detection Paradigm Research Articles

SeFi-CD: A Semantic First Change Detection Paradigm That Can Detect Any Change You Want

The existing change detection (CD) methods can be summarized as the visual-first change detection (ViFi-CD) paradigm, which first extracts change features from visual differences and then assigns them specific semantic information. However, CD is essentially dependent on change regions of interest (CRoIs), meaning that the CD results are directly determined by the semantics changes in interest, making its primary image factor semantic of interest rather than visual. The ViFi-CD paradigm can only assign specific semantics of interest to specific change features extracted from visual differences, leading to the inevitable omission of potential CRoIs and the inability to adapt to different CRoI CD tasks. In other words, changes in other CRoIs cannot be detected by the ViFi-CD method without retraining the model or significantly modifying the method. This paper introduces a new CD paradigm, the semantic-first CD (SeFi-CD) paradigm. The core idea of SeFi-CD is to first perceive the dynamic semantics of interest and then visually search for change features related to the semantics. Based on the SeFi-CD paradigm, we designed Anything You Want Change Detection (AUWCD). Experiments on public datasets demonstrate that the AUWCD outperforms the current state-of-the-art CD methods, achieving an average F1 score 5.01% higher than that of these advanced supervised baselines on the SECOND dataset, with a maximum increase of 13.17%. The proposed SeFi-CD offers a novel CD perspective and approach.

The Effects of the Complexity of 3D Virtual Objects on Visual Working Memory Capacity in AR Interface for Mobile Phones

The current study aims to investigate the effects of 3D virtual object complexity on visual working memory capacity in mobile augmented reality (MAR) interfaces. With the popularity of augmented reality technology in mobile applications, 3D virtual elements play a key role in interaction. However, prior studies ignored the correlation between virtual object presentation and visual working memory (VWM). Given that visual working memory capacity is closely related to overall cognitive ability, the current study explored the relationship between the complexity of 3D virtual objects and VWM capacity in AR interfaces. Sixty volunteers participated in a 5-point Likert scale rating to eliminate the interference factors of familiarity, concreteness and similarity in 3D virtual material objects. Then, we further conducted an MAR change detection paradigm experiment and successfully manipulated the complexity of 3D virtual objects and the set size. Thirty-one subjects completed the formal experiment. Three measurements (reaction time, proportion correct, and Cowan’s K) were analyzed for nine experimental conditions (three object complexity levels and three object set sizes). The results confirmed that the visual working memory capacity in mobile AR interfaces is modulated by the complexity of the 3D virtual objects and set size, which decreases with the increase in complexity and set size of the displayed 3D virtual objects. As the complexity of the 3D virtual objects increases, the amount of resources allocated to each item decreases, resulting in a decrease in memory capacity and memory accuracy. This study highlights the effectiveness of VWM capacity in MAR interface design research and provides valuable insights into determining the best way to present 3D virtual objects.

Working Memory Capacity for Mid-Air Gestures in Human–Computer Interaction

Mid-air gesture interactions have emerged as one of the predominant modalities used in human-computer interaction (HCI). However, extant research on gestures predominantly concentrates on the design of gestures for singular functionalities, which requires a comprehensive investigation into gesture interaction design from an integrative HCI system perspective. Working memory capacity plays a pivotal role in constraining the number of gestures accommodated within an HCI system. This study adopts the change detection paradigm to conduct an empirical investigation into the working memory capacities associated with mid-air gestures, aiming to elucidate the working memory capacity for such gestures. The experimental design included two independent variables: five distinct categories of mid-air gestures (physical, symbolic, metaphorical, abstract, and mixed) and memory set sizes ranging from two to nine items. The findings revealed that working memory capacities for different types of gestures fluctuate between three and five items, with symbolic gestures presenting the most negligible cognitive load for recall and abstract gestures proving to be the most challenging. The outcomes of this research have significant implications for both the design of individual gestures and the overarching design of gesture interaction systems, serving as a valuable reference for future endeavors in HCI design optimization.

Does Stimulus Category Coherence Influence Visual Working Memory? A Rational Analysis.

Visual working memory (VWM) refers to the temporary storage and manipulation of visual information. Although visually different, objects we view and remember can share the same higher-level category information, such as an apple, orange, and banana all being classified as fruit. We study the influence of category information on VWM, focusing on the question of whether stimulus category coherence (i.e., whether all to-be-remembered items belong to the same semantic category) influences VWM performance. This question is addressed in two behavioral experiments using a change-detection paradigm and a rational analysis using an ideal observer based on a Bayesian model. Both experimental participants and the ideal observer often, but not always, performed numerically better on coherent trials (i.e., when all stimuli belonged to the same category). We hypothesize that the influence of category coherence information on VWM may be task-dependent and/or stimulus-dependent. In conditions when category coherence information is highly valuable for task performance, as indicated by the ideal observer, then participants tended to make use of it. However, when the ideal observer suggested this information was not crucial to performance, participants did not. In addition, both participants and the ideal observer showed a bias toward responding "same," and often showed a stronger influence of category coherence on change trials. The consistencies between participant and ideal observer responses suggest participants often behaved as they did because these behaviors are optimal (or approximately so) for maximizing task performance. This may help explain conflicting results reported in the scientificliterature.

Not fully remembered, but not forgotten: interfering sounds worsen but do not eliminate the representation of pitch in working memory.

Recent research has begun measuring auditory working memory with a continuous adjustment task in which listeners adjust attributes of a sound to match a stimulus presented earlier. This approach captures auditory memory's continuous nature better than standard change detection paradigms that collect binary ("same or different") memory measurements. In two experiments, we assessed the impact of different interference stimuli (multitone complexes vs. white noise vs. silence) on the precision and accuracy of participants' reproductions of pitch from memory. Participants were presented with a target multitone complex stimulus followed by eight successive interference signals. Across trials, these signals alternated between additional multitone complexes, randomly generated white noise samples, or (in Experiment 2) silence. This was followed by a response period where participants adjusted the pitch of a response stimulus using a MIDI touchpad to match the target. Experiment 1 found a significant effect of interference type on performance, with tone interference signals producing the greatest impairments to participants' accuracy and precision compared to white noise. Interestingly, it also found a compression in the participants' responses, with overestimations of low-frequency targets and underestimations for high-frequency targets. Experiment 2 replicated results from Experiment 1, with an additional silence condition showing the best performance, suggesting that non-tonal signals also generate interference. In general, results support a shared resource model of working memory with a limited capacity that can be flexibly allocated to hold items in memory with varying levels of fidelity. Interference does not appear to knock items out of a fixed precision slot, but rather robs a portion of capacity from stored items.

Remembering Sets: Capacity Limit and Time Limit of Ensemble Representations in Working Memory.

In a constantly changing visual environment, the ability to extract and store ensemble representations plays a crucial role in efficiently processing and remembering complex visual information. However, how working memory maintains these ensemble representations remains unclear. Therefore, the present study aimed to investigate the limits and characteristics of ensemble representations in working memory using a change detection paradigm. Participants were presented with multiple sets of circles grouped by spatial proximity and were asked to memorize the mean diameter of the circles in each set. Results showed that working memory could stably maintain mean sizes of approximately two sets for at least four seconds. Moreover, the memory performance of ensembles was not affected by the number of circles within a set, suggesting that individual details were not stored in working memory. These results suggest that the visual system can effectively store ensembles in working memory without preserving detailed individual information.

Locations of objects are better remembered than their identities in naturalistic scenes: An eye-tracking experiment in mild cognitive impairment.

Retaining the identity or location of decontextualized objects in visual short-term working memory (VWM) is impaired by healthy and pathological ageing, but research remains inconclusive on whether these two features are equally impacted by it. Moreover, it is unclear whether similar impairments would manifest in naturalistic visual contexts. 30 people with mild cognitive impairment (MCI) and 32 age-matched control participants (CPs) were eye-tracked within a change detection paradigm. They viewed 120 naturalistic scenes, and after a retention interval (1 s) asked whether a critical object in the scene had (or not) changed on either: identity (became a different object), location (same object but changed location), or both (changed in location and identity). MCIs performed worse than CP but there was no interaction with the type of change. Changes in both were easiest while changes in identity alone were hardest. The latency to first fixation and first-pass duration to the critical object during successful recognition was not different between MCIs and CPs. Objects that changed in both features took longer to be fixated for the first time but required a shorter first pass compared to changes in identity alone which displayed the opposite pattern. Locations of objects are better remembered than their identities; memory for changes is best when involving both features. These mechanisms are spared by pathological ageing as indicated by the similarity between groups besides trivial differences in overall performance. These findings demonstrate that VWM mechanisms in the context of naturalistic scene information are preserved in people with MCI. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

BFASTm-L2, an unsupervised LULCC detection based on seasonal change detection – An application to large-scale land acquisitions in Senegal

In the context of Global Change Research, detection, monitoring and characterization of land use/land cover (LULC) changes are of prime importance. The increasing availability of dense satellite image time series (SITS) has led to a shift in the change detection paradigm, with algorithms able to exploit the full temporal information laid down in SITS. So far, most of these algorithms have focused on the detection of abrupt and gradual changes, and thus developed breakpoint detection based on significant deviations from the mean. However, LULC changes may manifest themselves in other patterns, particularly changes in seasonality (amplitude, number and length of the growing seasons) that are harder to detect. In this paper, we propose a simple method to automatically select the breakpoint linked to the biggest seasonal change in long and dense SITS with multiple breakpoints. This approach - BFASTm-L2 - relies on linking a high-speed algorithm (BFAST monitor) with a time series similarity metric (Euclidian distance L2) sensitive to seasonal changes. The capacity of BFASTm-L2 to identify the date of change in different situations was tested on two data sets, and compared to the performances of three other algorithms (BFAST monitor, BFAST lite, and Edyn). The data sets are 1. a published benchmark data set composed of 25 200 simulated SITS with different change types and change magnitudes, and 2. the 2000–2020 MODIS NDVI SITS over a 200x200 pixels area in Senegal including different study sites which have undergone recent LULC changes due to agricultural large-scale land acquisitions (LSLAs) (as reported in the ground field database used in this study). The results show that BFASTm-L2 is efficient in accurately detecting in time most of the changes, and, in contrast with BFAST Lite and BFASTmonitor, to spatially highlight LSLAs-induced changes without the need of any prior knowledge. The automatic proposed approach, faster than BFAST Lite and Edyn, and with very few tuneable parameters, may thus be easily implemented in unsupervised pipelines to map and analyse generic LULC changes at regional scale.

Differences in the detail: Metacognition is better for seen than sensed changes to visual scenes

Metacognition is the process by which we know what we know. Knowing has both declarative and sensed components. Differences exist in the information that moves to our conscious awareness and how it is synthesised with existing knowledge. The current study measured metacognition by extending a visual change detection paradigm that promoted explicit or implicit detection by either a local or global manipulation of a scene. A within-subjects design was used to investigate how 91 participants detected change and made metacognitive judgements. Cognitive modelling, based on confidence judgements, estimated the relative contributions of discrete and continuous cognitive processes to change detection, and to metacognition. Metacognition was sensitive to both the discrete and continuous processes underlying change detection, but was more sensitive to the discrete process. These results demonstrate that metacognition attunes confidence differentially to explicit and implicit processes, and support direct-access theories for discrete processing and meta-representation theories for continuous processing.

A pilot study on the evaluation of cognitive abilities’ cluster through game-based intelligent technique

AbstractNumerous scientific studies measured cognitive abilities through administered tests. Most of these traditional tests are inappropriate for several reasons, such as cost-ineffectiveness, tiresomeness, and invasiveness. The need is to build cost-effective, exciting, and plausibly engaging techniques that could noninvasively measure cognitive abilities. This paper presents LAS, an intelligent technique that utilizes non-invasively collected game analytics to automatically evaluate the cluster of three cognitive abilities (i.e., Visual Long-term Memory (VLTM), Analytical Capability (AC), and Visual Short-term Memory in Change Detection Paradigm (VSTMiCDP)). The experimental group-based cross-generational cognitive evaluation in the game-based scenario established the potential of the proposed technique is twofold: 1) It successfully categorizes cluster of three targeted cognitive abilities within the 5-point evaluation sphere (i.e., 0–1 = very bad, 1–2 = bad, 2–3 = fair, 3–4 = good, 4–5 = excellent), and 2) It highly correlates with the results of a control group that are measured with three traditional cognitive tests.

Are social interactions preferentially attended in real-world scenes? Evidence from change blindness.

In change detection paradigms, changes to social or animate aspects of a scene are detected better and faster compared with non-social or inanimate aspects. While previous studies have focused on how changes to individual faces/bodies are detected, it is possible that individuals presented within a social interaction may be further prioritised, as the accurate interpretation of social interactions may convey a competitive advantage. Over three experiments, we explored change detection to complex real-world scenes, in which changes either occurred by the removal of (a) an individual on their own, (b) an individual who was interacting with others, or (c) an object. In Experiment 1 (N = 50), we measured change detection for non-interacting individuals versus objects. In Experiment 2 (N = 49), we measured change detection for interacting individuals versus objects. Finally, in Experiment 3 (N = 85), we measured change detection for non-interacting versus interacting individuals. We also ran an inverted version of each task to determine whether differences were driven by low-level visual features. In Experiments 1 and 2, we found that changes to non-interacting and interacting individuals were detected better and more quickly than changes to objects. We also found inversion effects for both non-interaction and interaction changes, whereby they were detected more quickly when upright compared with inverted. No such inversion effect was seen for objects. This suggests that the high-level, social content of the images was driving the faster change detection for social versus object targets. Finally, we found that changes to individuals in non-interactions were detected faster than those presented within an interaction. Our results replicate the social advantage often found in change detection paradigms. However, we find that changes to individuals presented within social interaction configurations do not appear to be more quickly and easily detected than those in non-interacting configurations.

How are patterned movements stored in working memory?

In this study, the change detection paradigm was used to study the working memory of patterned movements and the relationship of this type of memory with the visuospatial sketchpad in three experiments. Experiment 1 measured participants' working memory capacity for patterned movements and explored the influence of stimulus type with indicators such as response time and accuracy rate. Experiments 2 and 3 explored the relationship between patterned movements and the visual and spatial subsystems, respectively. The results of Experiment 1 indicated that individuals can store 3-4 patterned movements in working memory; however, a change in stimulus format or an increase in memory load may decrease the speed and efficiency of working memory processing. The results of Experiment 2 showed that working memory and visual working memory are independent when processing patterned movements. The results of Experiment 3 showed that the working memory of patterned movements was affected by spatial working memory. Changes in stimulus type and memory load exerted different effects on the working memory capacity of participants. These results provide behavioral evidence that the storage of patterned movement information is independent of the visual subsystem but requires the spatial subsystem of the visuospatial sketchpad.

Sequential encoding paradigm reliably captures the individual differences from a simultaneous visual working memory task.

Converging behavioral and neural evidence have suggested that visual stimuli could be attached to existing visual working memory sequentially in time. However, whether individual differences in sequential visual working memory paradigm are similar to those measured by the classical simultaneous change detection paradigm remain unknown. Here, we first show that sequentially presented visual stimuli exhibit similar working memory capacity bottlenecks as previous research using simultaneously presented items. We further reveal that within the same subject, the accuracy and capacity estimates using sequential and simultaneous paradigm were comparable across four different set sizes. Also, we discover that the individual differences measured by the sequential paradigm were highly correlated to those by the simultaneous paradigm within the same subject across all four set sizes of interest. Finally, we find that in a larger sample of subjects (n = 200), the variance and higher-order statistics were similar for sequential and simultaneous paradigms with set size of 6. Collectively, these findings indicate that individual differences measured by the sequential presentation of visual items rely on the similar working memory resources as those by the simultaneous form of presentation.

Visual Short-Term Memory Persists Across Multiple Fixations: An n-Back Approach to Quantifying Capacity in Infants and Adults

Visual short-term memory (STM) is a foundational component of general cognition that develops rapidly during the first year of life. Although previous research has revealed important relations between overt visual fixation and memory formation, it is unknown whether infants can maintain distinct memories for sequentially fixated items or remember nonfixated array items. Participants (5-month-olds, 11-month-olds, and adults; n = 24 at each age) from the United States were tested in a passive change-detection paradigm with an n-back manipulation to examine memory for the last fixated item (one-back), second-to-last fixated item (two-back), or nonfixated item (change-other). Eye tracking was used to measure overt fixation while participants passively viewed arrays of colored circles. Results for all ages revealed convergent evidence of memory for up to two sequentially fixated objects (i.e., one-back, two-back), with moderate evidence for nonfixated array items (change-other). A permutation analysis examining change preference over time suggested that differences could not be explained by perseverative looking or location biases.

Lateral Bias in Visual Working Memory

The present study aimed to evaluate functional cerebral asymmetries of visual working memory (VWM) in relation to language lateralization. The bilateral change detection paradigm with capital letters as stimuli and the translingual lexical decision task were used to assess VWM and language asymmetry, respectively, in a sample of 99 younger healthy participants (59 women). Participant attention was cued towards right or left visual half-field. For the VWM task, men and women were more accurate and faster when stimuli were presented in the right visual half-field compared to the left visual half-field. As expected, a significant right visual half-field advantage was demonstrated in the lexical decision task in performance accuracy (but not response time). The results also revealed no relationship between lateralization in VWM and lexical decision. VWM performance accuracy decreased significantly with increasing asymmetry. This relationship was significant for women, but not men. Taken together, the present study demonstrates that the lateral bias in visual working memory is independent from language lateralization, and less lateralized individuals perform better than individuals with larger asymmetries in both visual half-field tasks.

Change localization: A highly reliable and sensitive measure of capacity in visual working memory.

The change detection paradigm has been a widely used approach for measuring capacity in visual working memory (WM). In this task, subjects see an array of visual items, followed by a short blank delay and a single test item. Their task is to indicate whether that test item changed relative to the item in the sample array. This task provides reliable measurements of WM capacity that exhibit robust correlations with many outcome variables of interest. Here, we offer a new variant of this task that we call "change localization." This task is closely modeled after the change detection task described above, except that the test array contains the same number of items as the sample array, and one item has always changed in each trial. The subject's task is to select the changed item in the test array. Using both color and shape stimuli, scores in the change localization task were highly correlated with those in the change detection task, suggesting that change localization taps into the same variance in WM ability. Moreover, the change localization task was far more reliable than change detection, such that only half the number of trials were required to achieve robust reliability. To further validate the approach, we replicated known effects from the literature, demonstrating that they could be detected with far fewer trials than with change detection. Thus, change localization provides a highly reliable and sensitive approach for measuring visual working memory capacity.

Perceptual bias contextualized in visually ambiguous stimuli

The visual appearance of an object is a function of stimulus properties as well as perceptual biases imposed by the observer. The context-specific trade-off between both can be measured accurately in a perceptual judgment task, involving grouping by proximity in ambiguous dot lattices. Such grouping depends lawfully on a stimulus parameter of the dot lattices known as their aspect ratio (AR), whose effect is modulated by a perceptual bias representing the preference for a cardinal orientation. In two experiments, we investigated how preceding context can lead to bias modulation, either in a top-down fashion via visual working memory (VWM) or bottom-up via sensory priming. In Experiment 1, we embedded the perceptual judgment task in a change detection paradigm and studied how the factors of VWM load (complexity of the memory array) and content (congruency in orientation to the ensuing dot lattice) affect the prominence of perceptual bias. A robust vertical orientation bias was observed, which was increased by VWM load and modulated by congruent VWM content. In Experiment 2, dot lattices were preceded by oriented primes. Here, primes regardless of orientation elicited a vertical orientation bias in dot lattices compared to a neutral baseline. Taken together, the two experiments demonstrate that top-down context (VWM load and content) effectively controls orientation bias modulation, while bottom-up context (i.e., priming) merely acts as an undifferentiated trigger to perceptual bias. These findings characterize the temporal context sensitivity of Gestalt perception, shed light on the processes responsible for different perceptual outcomes of ambiguous stimuli, and identify some of the mechanisms controlling perceptual bias.

Are infants' preferences in the number change detection paradigm driven by sequence patterns?

Inter-individual differences in infants' numerosity processing have been assessed using a change detection paradigm, where participants were presented with two concurrent streams of images, one alternating between two numerosities and the other showing one constant numerosity. While most infants look longer at the changing stream in this paradigm, the reasons underlying these preferences have remained unclear. We suggest that, besides being attracted by numerosity changes, infants perhaps also respond to the alternating pattern of the changing stream. We conducted two experiments (N=32) with 6-month-old infants to assess this hypothesis. In the first experiment, infants responded to changes in numerosity even when the changing stream showed numerosities in an unpredictable random order. In the second experiment, infants did not display any preference when an alternating stream was pitted against a random stream. These findings do not provide evidence that the alternating pattern of the changing stream contributes to drive infants' preferences. Instead, around the age of 6months, infants' responses in the numerosity change detection paradigm appear to be mainly driven by changes in numerosity, with different levels of preference reflecting inter-individual difference in the acuity of numerosity perception.

Change-detection training and its effects on visual processing skills

Previous cognitive training research with the change-detection paradigm found only sparse effects that went beyond improvements in the training task but stressed an increase in fidelity of internal memory representations. Motivated by the demanding visual processing requirements of change-detection training, we extended this work by focusing on whether training on a change-detection task would improve visual processing skills. Fifty participants were randomly assigned to train on a change-detection task or on a control task for seven sessions. Participants’ visual processing skills were assessed before and after the intervention, focusing on visual search, contrast sensitivity, and contour integration. Our results suggest a general improvement in perceptual skills that was primarily driven by a conjunction search task and to a much lesser extent by a complex visual search task and a contrast sensitivity task. The data from the conjunction search task further suggest a causal link between training and improvements of perceptual as opposed to attentional processes. Since the change-detection paradigm is commonly used to assess working memory capacity, future research needs to investigate how much of its variance is explained by memory performance and how much is explained by perceptual processes.

Modulation of similarity on the distraction resistance of visual working memory representation.

Controversy exists regarding the distraction resistance of priority items in visual working memory (VWM). The protection account proposes that high-priority items resist distraction more than low-priority items, while the vulnerability account proposes that distractors impair high-priority items more. We proposed another available resource threshold account: distraction will not impair items if available resources exceed their threshold needed for sufficient processing. Using a change-detection paradigm, we manipulated item priority by color similarity and inserted distractors during VWM retention. We investigated the effect of similarity on distraction resistance of relevant (color) and irrelevant (shape) feature representations (Experiments 1-2), and the neural mechanism of this effect using event-related potentials (ERPs; Experiment 3). Behavioral results showed distractors impaired the accuracy of dissimilar items when relevant features were memorized and of similar items when irrelevant features were memorized under simultaneous presentation of similar and dissimilar items. Moreover, distractors impaired the accuracy of dissimilar items when relevant features were memorized and of both similar and dissimilar items when irrelevant features were memorized under separate presentation of items. ERP results showed a smaller negative slow wave and P2 but larger N2 under the similar condition. Similarity protected relevant features of similar items against distraction by reducing memory load, decreasing attentional resources allocated to distractors, and strengthening inhibition of distractors. However, similarity did not protect irrelevant features of similar items. Our results support the available resource threshold account, suggesting that VWM is a flexible and intelligent system despite its limited capacity.