208 research outputs found

    Auditory grouping occurs prior to intersensory pairing: evidence from temporal ventriloquism

    Get PDF
    The authors examined how principles of auditory grouping relate to intersensory pairing. Two sounds that normally enhance sensitivity on a visual temporal order judgement task (i.e. temporal ventriloquism) were embedded in a sequence of flanker sounds which either had the same or different frequency (Exp. 1), rhythm (Exp. 2), or location (Exp. 3). In all experiments, we found that temporal ventriloquism only occurred when the two capture sounds differed from the flankers, demonstrating that grouping of the sounds in the auditory stream took priority over intersensory pairing. By combining principles of auditory grouping with intersensory pairing, we demonstrate that capture sounds were, counter-intuitively, more effective when their locations differed from that of the lights rather than when they came from the same position as the lights

    No effect of auditory–visual spatial disparity on temporal recalibration

    Get PDF
    It is known that the brain adaptively recalibrates itself to small (∼100 ms) auditory–visual (AV) temporal asynchronies so as to maintain intersensory temporal coherence. Here we explored whether spatial disparity between a sound and light affects AV temporal recalibration. Participants were exposed to a train of asynchronous AV stimulus pairs (sound-first or light-first) with sounds and lights emanating from either the same or a different location. Following a short exposure phase, participants were tested on an AV temporal order judgement (TOJ) task. Temporal recalibration manifested itself as a shift of subjective simultaneity in the direction of the adapted audiovisual lag. The shift was equally big when exposure and test stimuli were presented from the same or different locations. These results provide strong evidence for the idea that spatial co-localisation is not a necessary constraint for intersensory pairing to occur

    Global circulation patterns of seasonal influenza viruses vary with antigenic drift.

    Get PDF
    Understanding the spatiotemporal patterns of emergence and circulation of new human seasonal influenza virus variants is a key scientific and public health challenge. The global circulation patterns of influenza A/H3N2 viruses are well characterized, but the patterns of A/H1N1 and B viruses have remained largely unexplored. Here we show that the global circulation patterns of A/H1N1 (up to 2009), B/Victoria, and B/Yamagata viruses differ substantially from those of A/H3N2 viruses, on the basis of analyses of 9,604 haemagglutinin sequences of human seasonal influenza viruses from 2000 to 2012. Whereas genetic variants of A/H3N2 viruses did not persist locally between epidemics and were reseeded from East and Southeast Asia, genetic variants of A/H1N1 and B viruses persisted across several seasons and exhibited complex global dynamics with East and Southeast Asia playing a limited role in disseminating new variants. The less frequent global movement of influenza A/H1N1 and B viruses coincided with slower rates of antigenic evolution, lower ages of infection, and smaller, less frequent epidemics compared to A/H3N2 viruses. Detailed epidemic models support differences in age of infection, combined with the less frequent travel of children, as probable drivers of the differences in the patterns of global circulation, suggesting a complex interaction between virus evolution, epidemiology, and human behaviour.T.B. was supported by a Newton International Fellowship from the Royal Society and through NIH U54 GM111274. S.R. was supported by MRC (UK, Project MR/J008761/1), Wellcome Trust (UK, Project 093488/Z/10/Z), Fogarty International Centre (USA, R01 TW008246‐01), DHS (USA, RAPIDD program), NIGMS (USA, MIDAS U01 GM110721‐01) and NIHR (UK, Health Protection Research Unit funding). The Melbourne WHO Collaborating Centre for Reference and Research on Influenza was supported by the Australian Government Department of Health and thanks N. Komadina and Y.‐M. Deng. The Atlanta WHO Collaborating Center for Surveillance, Epidemiology and Control of Influenza was supported by the U.S. Department of 13 Health and Human Services. NIV thanks A.C. Mishra, M. Chawla‐Sarkar, A.M. Abraham, D. Biswas, S. Shrikhande, AnuKumar B, and A. Jain. Influenza surveillance in India was expanded, in part, through US Cooperative Agreements (5U50C1024407 and U51IP000333) and by the Indian Council of Medical Research. M.A.S. was supported through NSF DMS 1264153 and NIH R01 AI 107034. Work of the WHO Collaborating Centre for Reference and Research on Influenza at the MRC National Institute for Medical Research was supported by U117512723. P.L., A.R. & M.A.S were supported by EU Seventh Framework Programme [FP7/2007‐2013] under Grant Agreement no. 278433-­‐PREDEMICS and ERC Grant agreement no. 260864. C.A.R. was supported by a University Research Fellowship from the Royal Society.This is the author accepted manuscript. It is currently under infinite embargo pending publication of the final version

    Cellular Radiosensitivity: How much better do we understand it?

    Get PDF
    Purpose: Ionizing radiation exposure gives rise to a variety of lesions in DNA that result in genetic instability and potentially tumorigenesis or cell death. Radiation extends its effects on DNA by direct interaction or by radiolysis of H2O that generates free radicals or aqueous electrons capable of interacting with and causing indirect damage to DNA. While the various lesions arising in DNA after radiation exposure can contribute to the mutagenising effects of this agent, the potentially most damaging lesion is the DNA double strand break (DSB) that contributes to genome instability and/or cell death. Thus in many cases failure to recognise and/or repair this lesion determines the radiosensitivity status of the cell. DNA repair mechanisms including homologous recombination (HR) and non-homologous end-joining (NHEJ) have evolved to protect cells against DNA DSB. Mutations in proteins that constitute these repair pathways are characterised by radiosensitivity and genome instability. Defects in a number of these proteins also give rise to genetic disorders that feature not only genetic instability but also immunodeficiency, cancer predisposition, neurodegeneration and other pathologies. Conclusions: In the past fifty years our understanding of the cellular response to radiation damage has advanced enormously with insight being gained from a wide range of approaches extending from more basic early studies to the sophisticated approaches used today. In this review we discuss our current understanding of the impact of radiation on the cell and the organism gained from the array of past and present studies and attempt to provide an explanation for what it is that determines the response to radiation

    No effect of synesthetic congruency on temporal ventriloquism

    Get PDF
    A sound presented in temporal proximity to a light can alter the perceived temporal occurrence of that light (temporal ventriloquism). Recent studies have suggested that pitch–size synesthetic congruency (i.e., a natural association between the relative pitch of a sound and the relative size of a visual stimulus) might affect this phenomenon. To reexamine this, participants made temporal order judgements about small- and large-sized visual stimuli while high- or low-pitched tones were presented before the first and after the second light. We replicated a previous study showing that, at large sound–light intervals, sensitivity for visual temporal order was better for synesthetically congruent than for incongruent pairs. However, this congruency effect could not be attributed to temporal ventriloquism, since it disappeared at short sound–light intervals, if compared with a synchronous audiovisual baseline condition that excluded response biases. In addition, synesthetic congruency did not affect temporal ventriloquism even if participants were made explicitly aware of congruency before testing. Our results thus challenge the view that synesthetic congruency affects temporal ventriloquism

    Inferring Visuomotor Priors for Sensorimotor Learning

    Get PDF
    Sensorimotor learning has been shown to depend on both prior expectations and sensory evidence in a way that is consistent with Bayesian integration. Thus, prior beliefs play a key role during the learning process, especially when only ambiguous sensory information is available. Here we develop a novel technique to estimate the covariance structure of the prior over visuomotor transformations – the mapping between actual and visual location of the hand – during a learning task. Subjects performed reaching movements under multiple visuomotor transformations in which they received visual feedback of their hand position only at the end of the movement. After experiencing a particular transformation for one reach, subjects have insufficient information to determine the exact transformation, and so their second reach reflects a combination of their prior over visuomotor transformations and the sensory evidence from the first reach. We developed a Bayesian observer model in order to infer the covariance structure of the subjects' prior, which was found to give high probability to parameter settings consistent with visuomotor rotations. Therefore, although the set of visuomotor transformations experienced had little structure, the subjects had a strong tendency to interpret ambiguous sensory evidence as arising from rotation-like transformations. We then exposed the same subjects to a highly-structured set of visuomotor transformations, designed to be very different from the set of visuomotor rotations. During this exposure the prior was found to have changed significantly to have a covariance structure that no longer favored rotation-like transformations. In summary, we have developed a technique which can estimate the full covariance structure of a prior in a sensorimotor task and have shown that the prior over visuomotor transformations favor a rotation-like structure. Moreover, through experience of a novel task structure, participants can appropriately alter the covariance structure of their prior

    Graded structure in sexual definitions: categorizations of having “had sex” and virginity loss among homosexual and heterosexual men and women

    Get PDF
    Definitions of sexual behavior display a robust hierarchy of agreement regarding whether or not acts should be classed as, for example, sex or virginity loss. The current research offers a theoretical explanation for this hierarchy, proposing that sexual definitions display graded categorical structure, arising from goodness of membership judgments. Moderation of this graded structure is also predicted, with the focus here on how sexual orientation identity affects sexual definitions. A total of 300 18- to 30-year-old participants completed an online survey, rating 18 behaviors for how far each constitutes having “had sex” and virginity loss. Participants fell into one of four groups: heterosexual male or female, gay male or lesbian. The predicted ratings hierarchy emerged, in which bidirectional genital acts were rated significantly higher than unidirectional or nonpenetrative contact, which was in turn rated significantly higher than acts involving no genital contact. Moderation of graded structure was also in line with predictions. Compared to the other groups, the lesbian group significantly upgraded ratings of genital contact that was either unidirectional or nonpenetrative. There was also evidence of upgrading by the gay male sample of anal intercourse ratings. These effects are theorized to reflect group-level variation in experience, contextual perspective, and identity-management. The implications of the findings in relation to previous research are discussed. It is suggested that a graded structure approach can greatly benefit future research into sexual definitions, by permitting variable definitions to be predicted and explained, rather than merely identified

    The Ubiquitin-Like Protein PLIC-1 or Ubiquilin 1 Inhibits TLR3-Trif Signaling

    Get PDF
    Background: The innate immune responses to virus infection are initiated by either Toll-like receptors (TLR3/7/8/9) or cytoplasmic double-stranded RNA (dsRNA)-recognizing RNA helicases RIG-I and MDA5. To avoid causing injury to the host, these signaling pathways must be switched off in time by negative regulators. Methodology/Principal Findings: Through yeast-two hybrid screening, we found that an ubiquitin-like protein named protein linking integrin-associated protein to cytoskeleton 1(PLIC-1 or Ubiquilin 1) interacted with the Toll/interleukin-1 receptor (TIR) domain of TLR4. Interestingly, PLIC-1 had modest effect on TLR4-mediated signaling, but strongly suppressed the transcriptional activation of IFN-β promoter through the TLR3-Trif-dependent pathway. Concomitantly, reduction of endogenous PLIC-1 by short-hairpin interfering RNA (shRNA) enhanced TLR3 activation both in luciferase reporter assays as well as in new castle disease virus (NDV) infected cells. An interaction between PLIC-1 and Trif was confirmed in co-immunoprecipitation (Co-IP) and GST-pull-down assays. Subsequent confocal microscopic analysis revealed that PLIC-1 and Trif colocalized with the autophagosome marker LC3 in punctate subcellular structures. Finally, overexpression of PLIC-1 decreased Trif protein abundance in a Nocodazole-sensitive manner. Conclusions: Our results suggest that PLIC-1 is a novel inhibitor of the TLR3-Trif antiviral pathway by reducing the abundance of Trif. © 2011 Biswas et al

    Factor structure of the Hospital Anxiety and Depression Scale in Japanese psychiatric outpatient and student populations

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>The Hospital Anxiety and Depression Scale (HADS) is a common screening instrument excluding somatic symptoms of depression and anxiety, but previous studies have reported inconsistencies of its factor structure. The construct validity of the Japanese version of the HADS has yet to be reported. To examine the factor structure of the HADS in a Japanese population is needed.</p> <p>Methods</p> <p>Exploratory and confirmatory factor analyses were conducted in the combined data of 408 psychiatric outpatients and 1069 undergraduate students. The data pool was randomly split in half for a cross validation. An exploratory factor analysis was performed on one half of the data, and the fitness of the plausible model was examined in the other half of the data using a confirmatory factor analysis. Simultaneous multi-group analyses between the subgroups (outpatients vs. students, and men vs. women) were subsequently conducted.</p> <p>Results</p> <p>A two-factor model where items 6 and 7 had dual loadings was supported. These factors were interpreted as reflecting anxiety and depression. Item 10 showed low contributions to both of the factors. Simultaneous multi-group analyses indicated a factor pattern stability across the subgroups.</p> <p>Conclusion</p> <p>The Japanese version of HADS indicated good factorial validity in our samples. However, ambiguous wording of item 7 should be clarified in future revisions.</p
    corecore