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The realization of rewritable and customizable electromagnetic illusions fundamentally hinges upon the ability to achieve precise spatiotemporal control over electromagnetic waves. Conventional metasurfaces are confined to globally stationary, periodic protocols, lacking the information entropy to orchestrate complex illusion patterns. Here, we introduce a modular metasurface time-domain programming framework that organizes discrete temporal modulation waveforms as reusable modulation units within a predefined library. By flexibly selecting and sequencing these units, rather than redesigning the entire control law for each new task, the framework redistributes the spectral components of the scattered field to synthesize diverse electromagnetic illusions. A deep generative model is established to map target illusions directly to specific time-domain modulation sequences. The metasurface executes these signals across distinct pulses to physically realize the user-defined illusion. Validated on a synthetic aperture imaging testbed, the system rewrites periodic baselines and synthesizes representative aperiodic illusion patterns under user-specified inputs, achieving high fidelity between intended objectives and measurements (structural similarity index ≥0.91). This work establishes a practical route from target-scene specification to executable metasurface control and provides a scalable paradigm for task-driven wave manipulation in radar imaging scenarios.

Children with Developmental Coordination Disorder (DCD) have deficits in visual perception and motor planning, which negatively impact motor learning. To address this, paradigms that manipulate visual perception during training have been proposed. This study investigated the influence of a visual illusion-based training paradigm, which alters the perceptual size of a target, on learning a beanbag throwing skill in children with DCD. A school- based randomized controlled trial was conducted in nine public schools. Seventy five males with DCD (Mean Age: 8.50&#x2009;&#xb1;&#x2009;.63, IQ&#x2009;>&#x2009;70) practiced a beanbag throwing task under one of three conditions: with a visual illusion inducing a perceptually smaller target (n&#x2009;=&#x2009;25), a perceptually larger target (n&#x2009;=&#x2009;25) and without visual illusion (n&#x2009;=&#x2009;25). Motor learning was assessed using a retention task at 48&#x2009;hours after the last practice session. The visual illusion significantly altered perceptions of target size. There were significant differences between the intervention groups in both the acquisition (F (2, 72)&#x2009;=&#x2009;29.75, p&#x2009;<&#x2009;.001) and retention (F (2, 72)&#x2009;=&#x2009;32.95, p&#x2009;<&#x2009;.001) phases, indicating that children with DCD demonstrated superior learning of the beanbag throwing task when the target was perceived as smaller than it actually was. These findings suggest that manipulating visual perception through illusions can be an effective clinical or educational strategy for enhancing motor skill training in children with DCD. This approach optimizes motor planning by providing a more constrained perceptual goal, offering a practical tool for motor interventions.

Viewing a prosthetic hand stroked at the same time and in the same place as a real hand hidden behind a screen can create the sense that the visible hand is one's own. This phenomenon, known as the rubber hand illusion (RHI), is a widely used paradigm to study the sense of body ownership. It has been hypothesized that RHI attenuates pain by altering body representation, which may in turn influence pain processing. However, the empirical findings remain inconsistent. This study aimed to (1) systematically review the literature on whether the RHI (compared with control conditions) modulates pain in healthy participants and (2) use a meta-analytic approach to determine whether the reported effect sizes from within-subjects experiments allow meaningful inferences to be drawn at the general population level. Our literature review revealed mixed and conflicting evidence regarding whether the RHI modulates pain intensity ratings or thresholds, with no consistent evidence for pain attenuation. The meta-analysis (k&#x202f;=&#x202f;22) results demonstrated a null effect (Hedges' g = 0.036) of the RHI on pain modulation, even when potential modulating factors were considered. These results do not support the hypothesis that the RHI attenuates pain and are inconsistent with theories suggesting that bodily illusions modulate the magnitude of pain experience, at least in healthy participants. The findings have implications for applied pain research and highlight the need for deeper investigations into the relationship between bodily illusions and pain perception to better understand the potential role of body ownership manipulations in clinical pain treatment.

The sound-induced flash illusion (SiFI) is a typical auditory-dominated multisensory illusion, and its susceptibility can be modified by perceptual training. However, the effects of different training protocols and their transfer effects on SiFI remain unclear. The present study employed the SiFI paradigm combined with feedback training to examine the effects of different types of training on SiFI performance across multiple stimulus onset asynchronies (SOAs). SOA was manipulated in the pretest and posttest to determine whether training effects would generalize to untrained temporal intervals. Participants were assigned to four groups, including a control group that completed only the pretest and posttest and three training groups that received 5 days of combined training, audiovisual training, or visual-only training respectively. The results showed that perceptual training significantly improved performance on the SiFI task, but the magnitude of improvement differed across training modalities. Audiovisual and combined training were more effective than visual-only training, and these benefits generalized from the trained SOA to untrained SOAs, indicating transfer of the training effect across temporal intervals. These findings suggest that cross-modal training is more effective than unimodal visual training in reducing SiFI susceptibility and provide further evidence for the plasticity of multisensory perceptual processing.

Previous studies have robustly illustrated the phenomenon of embodying additional body parts. For example, in the sixth finger illusion, the perception of an extra finger is generated by conflicting visuo-tactile stimulation via a mirror box. However, it remains unclear to what extent we can incorporate extra body parts into our body representation, when the additional body part in question belongs to someone else. By distorting the boundary between the self and the other in the sixth finger illusion, this present study explores whether it is possible to embody an extra finger which in fact belongs to someone else. Rather than using virtual reality or a prosthetic, a real-life volunteer took part in the experiment so that their little finger acted as the participant's extra digit. We tested two illusory variations featuring the volunteer: 'the Other' condition, in which the volunteer's little finger was placed palm-down next to the participant's little finger; and 'the Other Upwards' condition, in which the volunteer's little finger was placed palm-up next to the participant's little finger. Participants experienced strong body ownership over the volunteer's finger in both conditions, demonstrating that we can perceive someone else's finger to be our own as an extra digit on our hands. Moreover, we can do so even when the finger is anatomically incongruent with our own existing body structure. This study offers insight into the startling flexibility of our mental body representations, and suggests that it is possible to embody someone else's body part without having to establish a clear first-person perspective or disembody our own existing bodies. This is a compelling paradigm to explore the self-other boundary in relation to embodiment.

A short-term memory (STM) version of the Deese/Roediger-McDermott (DRM) paradigm was employed to investigate how true and false recognition evolved as STM contents were lost over a short time window immediately after initial encoding. Presentations of five-word DRM lists were followed by list-specific recognition tests applied either immediately or after a distractor-filled retention interval of 3, 9, or 27 s. Results showed a decrease in the probability of true recognition and an increase in the probability of false recognition as the retention interval grew longer. Based on the fuzzy-trace theory, we suggest that this pattern emerged from the different durability of item-specific phonological representations, which would play a dual role of supporting true memory and preventing false recognition, and integrative semantic representations, whose overlap with the critical items would give rise to the DRM illusion. As a further contribution, our study helps to establish the DRM illusion in STM as a genuine and robust phenomenon by showing that it can be observed even with no delay and no intervening distraction between study and test, and that it occurs when participants are explicitly warned about the presence of semantically related distractors and instructed not to be misled by them.

Semantic attraction is an illusion of plausibility that occurs when a noun with verb-matching semantic cues intervenes in the subject-verb agreement relation. Thus, a sentence like &#x201c;The drawer with the knife cuts&#x201d; tends to be perceived as more acceptable than &#x201c;The drawer with the handle cuts&#x201d; because cut and knife (the attractor) often co-occur. We report results from a self-paced reading experiment followed by two offline tasks (acceptability judgments and comprehension questions) that sought to examine the underlying factors in stronger or weaker semantic attraction effects. That was done by manipulating the frequency with which nouns co-occur with the verb and the cognitive load on working memory. The converging evidence reveals that online processing is rarely disturbed by implausible sentences, but their interpretation is directly linked to lexical co-occurrence and general contextual plausibility. Therefore, not only does acceptability in implausible sentences increase with the presence of an attractor but the degree to which the attractor shares features with the local noun can be a predictor of the likelihood of attraction, showing speakers&#x2019; sensitivity to plausible reading. That, in turn, suggests that in addition to a cue-based parsing mechanism, speakers' expectations, based on their world knowledge, seem to contribute to sentence interpretation.

It has been argued that the illusory truth effect - the tendency to judge repeated statements as more likely true - persists even when a statement is known to be false, whereas a competing view maintains that knowledge shields against such truth illusions. In this study, we reexamine two models of truth judgment that formalize these opposing perspectives: the fluency-conditional model (FCM), which assumes that repetition-induced fluency can override knowledge, and the knowledge-conditional model (KCM), which assumes that knowledge always takes precedence over fluency, such that fluency only becomes relevant in the complete absence of knowledge. Utilizing a novel two-alternative forced-choice paradigm, we derive and test critical qualitative predictions of each model. The results disconfirm the FCM while the KCM can be maintained. Quantitative assessments of both models corroborate this conclusion and extend it to some alternative model specifications. We further show that the FCM, as per its qualitative predictions, is incompatible with the assumption that repetition leads to a uniform increase in perceived plausibility. A continuous single-process model operating on this assumption aligns with the KCM's predictions but implies a different psychological mechanism. We conclude by outlining avenues for empirically dissociating these theoretical accounts.

Universal Health Coverage (UHC) promises access to care without financial hardship, yet in many low- and middle-income settings this ideal is undermined by pervasive informal payments. This perspective introduces the concept of the "illusion of free care" to explain how official fee-exemption policies coexist with hidden, off-the-record charges that reshape access and equity. Drawing on Somalia as a critical case of health system fragility, we argue that informal payments are not isolated acts of corruption but predictable responses to chronic underfunding, weak governance, and workforce precarity. We conceptualize this dynamic as a four-stage process linking policy promises, systemic constraints, the normalization of informal payments, and inequitable patient outcomes. These practices disproportionately exclude the poorest, erode trust, and stratify care along socioeconomic and gender lines. Conventional policy responses, including anti-corruption measures and nominally free care policies, fail to address underlying structural drivers. Achieving equitable UHC requires shifting from rhetorical commitments to systemic reforms in financing, workforce protection, and accountability.

During manual operations, the human brain relies on mediated visual stimuli such as color to estimate an object's weight and adjust muscle force through the central nervous system (CNS). This study examines the neuromuscular "reality gap" induced by the color-weight illusion (CWI) during repetitive lifting tasks in an augmented reality (AR) interface. We analyzed the median frequency (MDF) and Co-Contraction Index (CCI) of the biceps and triceps muscles to quantify physiological strain under varying luminance conditions in both AR and physical environments. The results reveal that AR significantly amplifies the CWI, with black stimuli triggering an aggressive joint-stiffening strategy in the AR group (APG). Compared with the physical reality group, the AR group showed lower overall endurance (91.4 &#xb1; 22.8 vs. 100.1 &#xb1; 12.5 repetitions) and a stronger physiological response to the black stimulus. In the AR group, the black condition was associated with a terminal CCI of 84.7 &#xb1; 25.4% and an MDF decline of approximately 21.7 Hz, whereas the corresponding contrast was attenuated in the physical reality group. These findings demonstrate a critical decoupling between behavioral output and internal physiological strain, indicating that the CNS treats virtual visual cues as high-reliability signals that increase metabolic "bio-cost" despite task completion parity. This research identifies a "masking effect" where behavioral metrics hide severe ergonomic risks, providing novel approaches for managing musculoskeletal health in industrial settings and personalizing coordination training in clinical rehabilitation.

The ST-elevation myocardial infarction (STEMI) paradigm relies on the assumption that specific millimeter-based ST-segment elevation criteria serve as a reliable surrogate for acute coronary occlusion. While proponents advocate for the simplicity and uniformity of these criteria, the paradigm often fails to reflect the underlying pathophysiologic reality captured in the Occlusion Myocardial Infarction (OMI) paradigm. A 65-year-old male presented with acute chest pain and an initial electrocardiogram (ECG) specific for left anterior descending coronary artery (LAD). Despite these findings, the ECG was negative for STEMI millimeter criteria. Management was delayed as the patient was categorized as having a non-ST elevation myocardial infarction (NSTEMI). Coronary angiography performed 15&#xa0;h after presentation revealed an acute total thrombotic occlusion of the LAD. This case illustrates the "illusion of simplicity" within the STEMI paradigm, where clinical documentation and intervention timing were dictated more by benchmark-driven diagnostic labels than by objective evidence of coronary occlusion. Evidence suggests that standard STEMI criteria fail to identify up to 38% of LAD occlusions, whereas expert interpretation and AI models have far higher sensitivity. The STEMI paradigm's purported uniformity is inconsistent over time and often reflects physician attainment of "door-to-balloon" metrics rather than the patient's physiological state. To improve diagnostic accuracy and patient outcomes, clinical practice must transition from the STEMI paradigm to the more physiologically accurate OMI paradigm.

Among many issues, Robot vision experiences illumination challenges very frequently. Existing Human Action Recognition techniques perform excellently in state of the art, instead of scarce consideration on the vital issue of illumination. The illumination concern becomes highly sensitive when the Robot observes a medical-related action. The illumination severely affects the correct recognition of the action. Resultantly, misclassification of a medical action may lead to irreparable loss. To gauge the sensitivity of the concern, the current study proposes a deep learning-based model I2I (Illusion to Illumination). The model effectually identifies medical actions even in dark environments with sufficient accuracy. I2I model depth data has been selected from the NTU RGB+D dataset to judge the efficacy. The features are extracted from depth data using the Histogram of Depth (HoD) and provided to the I2I model to recognize actions. A threshold mechanism is applied to select depth data's most prominent and valuable features. The efficacy and superiority of the I2I model are proven by comparing its performance with state-of-the-art research and provides 91.15% recognition accuracy.

Subjective color (SC) refers to chromatic perception induced by achromatic stimuli, as classically demonstrated using Benham's top. Despite nearly two centuries of investigation, the underlying neural mechanisms remain unclear. We developed artificial neural network models trained on natural videos using predictive learning to investigate SC generation. These models successfully reproduced artificial subjective color (ASC) from achromatic testing stimuli that contained no explicit chromatic information. Critically, ASC characteristics were systematically influenced by the colors of moving objects in the training videos. Using progressively simplified stimuli, ranging from natural scenes to 3D computer graphics and 2D animations, we demonstrated that the colors of moving objects primarily determine ASC properties. We propose that predictive learning establishes color associations with motion patterns, causing the arcs on Benham's top to be perceived as moving objects with corresponding colors. These findings suggest that cortical predictive mechanisms may complement retinal processes in generating subjective color phenomena.

Machine learning (ML) has become the dominant approach for predicting biological activity from molecular structure, yet its true ability to generalize beyond known chemical space remains uncertain. Although numerous models have been proposed, recent work suggests that simple similarity-based methods can perform on par with far more sophisticated architectures, raising questions about whether current approaches genuinely learn transferable structure-activity relationships. Here, we systematically examine how different dataset-splitting strategies affect the performance of k-nearest neighbors (k-NN) and a representative set of modern ML models. Across all splitting regimes, k-NN performs comparably to state-of-the-art methods. More importantly, as dataset splits become increasingly stringent and test molecules move further out-of-distribution (OOD), the predictive accuracy of all models deteriorates sharply, approaching random guessing. This collapse persists even when standard fingerprints are augmented with 3D geometric descriptors, indicating that many previously reported accuracies-typically obtained under nonrigorous splitting strategies-are likely inflated. These results underscore the need for more rigorous evaluation standards and the development of representations capable of supporting true OOD generalization.

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Visual and auditory information are seamlessly integrated when speech is perceived. This is illustrated by the McGurk effect, where incongruent visual information from the speaker's face alters the consonant the listener hears. However, it remains unclear how acoustic features of speech influence this illusion. In this study, perceptual data from 52 listeners exposed to McGurk stimuli (acoustic [pa] with visual [ka] spoken by four speakers) were combined with acoustic analyses of [pa], [ta], and [ka] to examine whether key features of plosive consonants, the noise burst, and formant transitions influence the effect. The following six acoustic cues of these features were analyzed: the center of gravity and duration of the noise burst and the frequency range and duration of the second and third formant transitions. Linear mixed modeling showed that most of these features contributed to the illusion, with the duration of the second formant transition being the strongest cue. In some cases, perception shifted as the acoustic difference decreased; for example, the McGurk stimulus was heard more as TA when the second formant transition of [pa] resembled that of [ta]. This study demonstrated that specific acoustic phonetic cues contribute systematically to the McGurk effect.

Two contemporary randomized trials of &#x3b2;-blocker therapy after myocardial infarction (MI) reached apparently conflicting conclusions. REBOOT, conducted in Spain and Italy, found no reduction in death or major cardiovascular events among patients with preserved ejection fraction. In contrast, the BETAMI-DANBLOCK study, conducted in Scandinavia, reported a modest but statistically significant reduction in a composite endpoint. The prevailing response has been to reconcile this divergence by elevating left ventricular ejection fraction-particularly the 40-49% range-as the decisive explanatory variable. This interpretation offers analytic simplicity but rests on fragile statistical and conceptual grounds. Drawing on Nancy Cartwright's account of causal capacities and Judea Pearl's transportability framework, this paper argues that &#x3b2;-blockers exhibit stable physiological effects whose clinical benefits depend on the causal environment. Randomization secures internal validity within trials but cannot homogenize genetic, systemic, or environmental contexts. Meta-analysis, by averaging across heterogeneous environments and individual treatment effects, risks obscuring rather than clarifying dependencies. The divergence between REBOOT and BETAMI-DANBLOCK does not represent a failure of evidence-based medicine but exposes the limits of reductionist interpretation. Rather than seeking universal truths, cardiovascular medicine should map the causal environments in which therapeutic capacities become manifest.

Tumor clonal evolution and spatiotemporal heterogeneity are key drivers of therapeutic resistance in melanoma, often driven by selection pressures generated by systemic therapy. Genetic testing plays a key role in guiding targeted therapies, but a single biopsy may not fully reflect the mutational landscape. This paper reports a case of metastatic acral melanoma that demonstrated dynamic branching clonal evolution under systemic therapeutic stress. The patient first underwent genetic testing in 2022.&#xa0;A 168-gene panel performed on a newly developed inguinal lymph node metastasis revealed only a TERT promoter mutation (c.-124C>T), with no KIT mutation detected. Disease progression despite multiple rounds of cytotoxic chemotherapy, antiangiogenic therapy, and immunotherapy. A 10-gene panel testing on the newly developed abdominal skin metastasis in 2024 revealed a rare KIT exon 18 mutation (p.Ala829Pro). However, the panel did not include the TERT gene. Then our retrospective single-gene testing of this abdominal skin metastasis confirmed the presence of concurrent TERT mutations. Retrospective testing of the primary acral lesion from 2019 showed that TERT and KIT mutations coexisted in a subclonal pattern. The variant allele frequency of KIT in the advanced cutaneous metastasis increased significantly, suggesting the possible occurrence allelic imbalance at the KIT gene locus. This case demonstrates that the KIT-mutant subclone in the advanced cutaneous metastasis was not newly acquired, but rather a pre-existing cell population that was selected for through a stringent therapeutic bottleneck. The study also showed the inherent resistance of the KIT p.Ala829Pro mutation to imatinib, explaining the failure of subsequent treatment. This study highlights the significant spatial and temporal heterogeneity of acral melanoma and underscores the critical importance of serial biopsies in accurately capturing clonal dynamics and guiding precision oncology therapy.

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