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    Categorical perception of tactile distance

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    The tactile surface forms a continuous sheet covering the body. And yet, the perceived distance between two touches varies across stimulation sites. Perceived tactile distance is larger when stimuli cross over the wrist, compared to when both fall on either the hand or the forearm. This effect could reflect a categorical distortion of tactile space across body-part boundaries (in which stimuli crossing the wrist boundary are perceptually elongated) or may simply reflect a localised increased in acuity surrounding anatomical landmarks (in which stimuli near the wrist are perceptually elongated). We tested these two interpretations, by comparing a well-documented bias to perceive mediolateral tactile distances across the forearm/hand as larger than proximodistal ones along the forearm/hand at three different sites (hand, wrist, and forearm). According to the ‘categorical’ interpretation, tactile distances should be elongated selectively in the proximodistal axis thus reducing the anisotropy. According to the ‘localised acuity’ interpretation, distances will be perceptually elongated in the vicinity of the wrist regardless of orientation, leading to increased overall size without affecting anisotropy. Consistent with the categorical account, we found a reduction in the magnitude of anisotropy at the wrist, with no evidence of a corresponding specialized increase in precision. These findings demonstrate that we reference touch to a representation of the body that is categorically segmented into discrete parts, which consequently influences the perception of tactile distance

    Daylight Spectrum Index: A New Metric to Assess the Affinity of Light Sources with Daylighting

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    The current scenario of colorimetry shows a wide variety of different metrics which do not converge in the assessment of the color rendering of light sources. The limitations of the Color Rendering Index have promoted the emergence of new metrics, such as the Color Quality Scale. As in the case of the previous metric, these new concepts are based on the analysis of the deviation of different color samples in a color space, contrasting the results with those obtained with a light source reference, which can vary depending on the color temperature. Within this context, the Daylight Spectrum Index is proposed. This new concept aims to determine the affinity with daylighting of electric light sources, comparing the resulting spectral power distributions of the lamps studied and that observed under natural light. The affinity of an electric light source with daylighting allows for lower energy consumption due to the better performance of human vision. The new metric proposed is evaluated following the results obtained from 80 surveys, demonstrating the usefulness of this new concept in the quantification of color rendering of LED lamps and the affinity of electric light sources with daylighting.Government of Spain BIA2017-86997-

    What explains entrepreneurial start-ups across countries: an integrative model

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    This research develops a multilevel framework to examine how resource-based antecedents shape individuals' decisions to start ventures via their perception of opportunities and how country-level characteristics pertaining to institutional development and institutional instability provide boundary conditions for the aforementioned associations. The empirical results show that entrepreneurial start-ups are positively affected by human capital resources and organisational resources, and that individuals’ perception of opportunities acts as a mediator within these relationships. In addition, the findings demonstrate that the proposed mediation effects are further bounded by country-specific institutional environments. The results offer new insights for the development of knowledge and theoretical bases by providing a multi-level perspective on how resource-based factors, perceived opportunity, and institutions operate as principal determinants that affect entrepreneurial start-ups. This paper complements and advances resource-based theory by integrating an approach that focuses on institutions and the pursuit of entrepreneurial opportunities to assess the mechanisms that are needed to release the potential of resources in venture creation more comprehensively. The research findings have implications and values for general managers who are keen to understand why heterogeneous resource is necessary and how it functions in their businesses, as well as how the process of managing resources needs to be aligned with their capabilities to identify and pursue business opportunities

    Motion extrapolation into the blind spot: Research report

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    The flash-lag effect, in which a moving object is perceived ahead of a colocalized flash, has led to keen empirical and theoretical debates. To test the proposal that a predictive mechanism overcomes neural delays in vision by shifting objects spatially, we asked observers to judge the final position of a bar moving into the retinal blind spot. The bar was perceived to disappear in positions well inside the unstimulated area. Given that photoreceptors are absent in the blind spot, the perceived shift must be based on the history of the moving object. Such predictive overshoots are suppressed when a moving object disappears abruptly from the retina, triggering retinal transient signals. No such transient-driven suppression occurs when the object disappears by virtue of moving into the blind spot. The extrapolated position of the moving bar revealed in this manner provides converging support for visual prediction. © Copyright © 2008 Association for Psychological Science
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