561975 research outputs found
Sort by
Minimal conditions for the emergence of a vicarious sense of agency toward artificial agents
No full textA Sense of Agency (SoA) is the feeling of being in control over own actions and their outcomes. However, people can also experience a “vicarious” SoA over the actions performed by other agents, including artificial agents. The present study aimed to understand the minimal conditions for vicarious SoA toward artificial agents. Specifically, we addressed whether vicarious SoA emerges when people have access only to the action effect (proximal and distal), i.e., when no motor action is executed. In addition, we manipulated the expectancy of the content of the distal effect of the action to check whether the proximal action effect is sufficient for the emergence of the vicarious SoA, or if this effect is due to the learned association between proximal and distal effects. In two experiments, participants performed an Intentional Binding (IB) task, where the IB effect was the behavioural measure of SoA. In the first experiment (Solo), participants judged the onset of self-generated tones, whereas in the second experiment, a new sample of participants judged the onset of tones produced by a computer via an automatically pressed button, i.e., a customized device designed to generate a keypress (proximal action effect) in the absence of an effector executing a keypress (no motor action). In both experiments, participants' neural activity was recorded via electroencephalography (EEG), to examine the N1 and P2 components as neural measures of SoA. Behavioural results across experiments showed that the IB effect always emerged, suggesting that the vicarious IB effect toward an artificial agent emerges when access to the proximal action effect is provided, even in the absence of the action itself. The neural results suggested that while individual (self) SoA seemed to partially rely on motor predictions indexed by the N1, vicarious SoA relies on later, more cognitive (although still predictive) processes indexed by the P2. Overall, these results suggest that individual and vicarious SoA, although behaviourally manifested through a similar IB effect, might – to some extent – rely on different neural mechanisms
Rubber voice illusion exposed neural correlates of voice perception and vocal adaptation across the continuum of psychosis
No full textThe Rubber Voice Illusion is an auditory analogue of the classic Rubber Hand Illusion, a “mind-trick” for the voice. When speakers hear a stranger’s utterances that are perfectly time‑locked and syllable‑matched to their own voice, many momentarily adopt that alien voice as self‑generated. We used this illusion to probe the integrity of predictive auditory mechanisms across the psychosis continuum. Sixty healthy adults completed three Talk‑Listen conditions while high‑density EEG was recorded: veridical (live playback of own voice), stranger‑match (congruent stranger voice) and stranger‑mismatch (incongruent). Behaviorally, only the congruent condition evoked a sense of Ownership and Agency over the stranger’s voice, paired with an upward shift in fundamental frequency toward the higher-pitched stranger voice - an implicit indication of voice adaptation. Neurophysiologically, the canonical speaking-induced suppression was replicated, and suppression was significantly smaller in participants who scored high on Peters et al. Delusions Inventory. In controls, greater pitch shift was associated with stronger neural suppression, suggesting a functioning self-suppression mechanism; conversely, in high-schizotypy individuals, the relationship reversed, despite pitch shifting toward the stranger’s pitch, they exhibited reduced suppression, indicating decoupling between motor output and sensory prediction. The study provides further evidence to the intricate relationship of neural mechanisms underlying self-generated actions with sensory processing in the psychosis continuum
The effects of eccentric versus traditional resistance training on muscle strength, power, hypertrophy, and functional performance in older adults: A systematic review with multilevel meta-analysis of randomized controlled trials
No full textThis systematic review and meta-analysis aimed to examine the effects of eccentric resistance training (ERT) versus traditional resistance training (TRT) on muscle strength, power, hypertrophy, and functional capacity in healthy older adults. Eleven randomized-controlled-trials were included. Between-group analysis for strength demonstrated a small but significant effect in favour of ERT over TRT (standardized-mean-difference [SMD]=0.27). No significant differences were found for functional capacity (SMD=0.12), muscle power (SMD=0.20), or hypertrophy (SMD=-0.03). Within-group analyses for ERT indicated large, significant effects for strength (SMD=0.96) and functional capacity (SMD=1.09) with no significant effects for power and hypertrophy. For TRT, large and moderate significant effects were found for functional capacity (SMD=0.94) and strength (SMD=0.59), respectively, with no significant effects for power and hypertrophy. Meta-regression analysis indicated that longer intervention durations were approaching-significance in their association with greater muscle strength gains with ERT than TRT (p = 0.09). With ERT, increasing age was significantly associated with greater muscle power gains (p = 0.04) and more sessions were approaching-significance in their association with hypertrophy (p = 0.08). Regarding TRT, a higher proportion of female participants was approaching-significance in its association with greater functional capacity gains (p = 0.09). In summary, ERT yields slightly greater muscle strength gains than TRT in older adults, while both produced comparable effects on functional capacity, muscle power, and hypertrophy. The two training modalities elicit moderate-to-large within-group improvements in strength and functional capacity but not in power or hypertrophy. ERT outcomes appear to be moderated by training duration, session number, and age, whereas TRT effects relate to female proportion. Overall, both modalities are effective for older adults, with a slight strength advantage for ERT
Metabolic adaptations of Qingke: A review of stress resilience and nutritional functions
No full textQingke, a staple crop grown on the high-altitude Tibetan Plateau, has evolved a metabolomic profile providing both environmental stress resilience and human nutrition. We review the hypothesis that the metabolites that confer cold and UV resistance on the crop also facilitate human adaptation to high-altitude stresses. Specifically, β-glucans regulate blood glucose primarily via short-chain fatty acids (SCFAs) produced through gut microbiota fermentation, which directly mediate glucose homeostasis. Phenolamides accumulate via the phenylpropanoid pathway, with chalcone isomerase (CHI) serving as a key enzyme in flavonoid biosynthesis and enhancing UV-B resistance. Under low temperatures, β-glucans improve frost tolerance by modulating osmotic balance and inhibiting ice-nucleating proteins, while lipids maintain membrane fluidity to sustain cellular function during cold stress. Importantly, we explore the hypothesis that these same metabolites, upon consumption, may facilitate human adaptation to high-altitude stresses. This hypothesis is supported by preliminary epidemiological associations between Qingke consumption and favorable health outcomes in high-altitude populations, as well as established bioactivities of the implicated metabolites in vitro and in animal models. However, direct causal evidence in humans and a comprehensive understanding of the underlying molecular mechanisms remain key knowledge gaps that warrant future investigation. Qingke as a unique resource at the interface of agricultural resilience and human nutrition. Understanding its metabolic blueprint will inform the development of functional foods and climate-resilient crops
Justice through proximity: theoretical foundations and practical applications of collaborative justice
No full textA de Rham weight part of Serre's conjecture and generalized mod p BGG decompositions
No full textWe propose the use of de Rham cohomology of special fibers of Shimura varieties to formulate a geometric version of the weight part of Serre's conjecture. We conjecture that this formulation is equivalent to the one using Serre weights and the étale cohomology of Shimura varieties. We prove this equivalence for generic weights and generic non-Eisenstein eigensystems for a compact Shimura variety such that . We do this by proving a generic concentration in middle degree of mod de Rham cohomology with coefficients. In turn, we prove this generic concentration by constructing generalized mod BGG decompositions for de Rham cohomology. After applying the results from our companion paper, this reduces to computing some BGG-like resolutions in a certain mod version of category , which is the main content of the article. In the case we also compute some explicit BGG decompositions, and assuming the generic concentration in middle degree of de Rham cohomology we obtain an improvement on the main result of arxiv:2410.09602
A chiral fermionic valve driven by quantum geometry
No full textMultifold topological semimetals host fermions with opposite chiralities at topological band crossings1,2,3. Chiral fermionic transport in topological systems often relies on high magnetic fields or magnetic dopants to suppress trivial transport and create an imbalance in occupancy of opposite Chern-number states4,5. Here we use the quantum geometry6,7 of topological bands to filter fermions by chirality into distinct Chern-number-polarized states. This allows for the real-space separation of currents with opposite fermionic chiralities, which we have demonstrated by observing their quantum interference in the absence of any magnetic field. Devices fabricated from single-crystal PdGa in a three-arm geometry exhibit quantum-geometry-induced anomalous velocities8,9 of chiral fermions, thereby exhibiting a nonlinear Hall effect. The resultant transverse chiral currents with opposite anomalous velocities are thereby spatially separated into the outer arms of the device. These chiral currents in opposing Chern number states also carry orbital magnetizations with opposite signs. The mesoscopic phase coherence of these chiral currents facilitated their quantum interference10 in a Mach–Zehnder interferometer. Our findings establish a chiral fermionic valve that exhibits three key properties: spatially separates chiral fermions into Chern-number polarized states by using their quantum geometry, enables tuneable current-induced magnetization and provides a platform for controllable quantum interference of chiral quasiparticles using an electric current and magnetic field
The dual twistor theory of self-dual black holes
No full textThe Taub-NUT and Eguchi-Hanson gravitational instantons, along with the self-dual Plebanski-Demianski metric, form a set of Euclidean metrics which can naturally be called `self-dual black holes', as they arise from self-dual slices of the most general vacuum, asymptotically flat black hole metric. These self-dual black holes are of interest for many reasons, and can famously be described through the non-linear graviton construction of twistor theory. However, the implicit nature of this twistor description obscures some features of the underlying geometry, particularly for the most general self-dual black holes. In this paper, we give a new construction of all asymptotically flat self-dual black holes based on holomorphic quadrics in flat dual twistor space, rather than the usual twistor space associated with self-duality. Remarkably, the geometry of the self-dual black holes -- including their hyperkahler structure, as well as Kerr-Schild and Gibbons-Hawking forms -- is directly encoded in the corresponding quadric. As a consequence, we obtain a previously unknown single Kerr-Schild form of the self-dual Plebanski-Demianski metric