10,029 research outputs found

    The role of human ventral visual cortex in motion perception.

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    Visual motion perception is fundamental to many aspects of visual perception. Visual motion perception has long been associated with the dorsal (parietal) pathway and the involvement of the ventral 'form' (temporal) visual pathway has not been considered critical for normal motion perception. Here, we evaluated this view by examining whether circumscribed damage to ventral visual cortex impaired motion perception. The perception of motion in basic, non-form tasks (motion coherence and motion detection) and complex structure-from-motion, for a wide range of motion speeds, all centrally displayed, was assessed in five patients with a circumscribed lesion to either the right or left ventral visual pathway. Patients with a right, but not with a left, ventral visual lesion displayed widespread impairments in central motion perception even for non-form motion, for both slow and for fast speeds, and this held true independent of the integrity of areas MT/V5, V3A or parietal regions. In contrast with the traditional view in which only the dorsal visual stream is critical for motion perception, these novel findings implicate a more distributed circuit in which the integrity of the right ventral visual pathway is also necessary even for the perception of non-form motion

    The Argument of Master Nicholas Fuller in the Case of Thomas Lad and Richard Maunsell, His Clients : Wherein It Is Plainely Proved, That the Ecclesiasticall Commissioners Have No Power, by Vertue of Their Commission, to Imprison, to Put to the Oath Ex Officio, or to Fine Any of His Majesties Subjects

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    This is a text by English lawyer Nicholas Fuller, published in the year 1607. The writings detail the legal case of Thomas Lad and Richard Maunsell vs. the Ecclesiastical Commissioners who charged the men with refusing to take the ex officio oath. Fuller sets out to prove, through this text, that the Ecclesiastical Commissioners do not have the power to imprison individuals, as they did with Lad and Maunsell. Fuller makes five points in his argument to prove stance.https://openworks.wooster.edu/notestein/1007/thumbnail.jp

    Citation analysis of Canadian psycho-oncology and supportive care researchers

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    Purpose: The purpose of this study was to conduct a historical review of psycho-oncology and supportive care research in Canada using citation analysis and to review the clinical impact of the research conducted by the most highly cited researchers. Methods: The lifetime journal publication records of 109 psycho-oncology and supportive care researchers in Canada were subject to citation analysis using the Scopus database, based on citations since 1996 of articles deemed relevant to psychosocial oncology and supportive care, excluding selfcitations. Three primary types of analysis were performed for each individual: the number of citations for each journal publication, a summative citation count of all published articles, and the Scopus h-index. Results: The top 20 psycho-oncology/supportive care researchers for each of five citation categories are presented: the number of citations for all publications; the number of citations for first-authored publications; the most highly cited first-authored publications; the Scopus h-index for all publications; and the Scopus h-index for first-authored publications. The three most highly cited Canadian psychooncology researchers are Dr. Kerry Courneya (University of Alberta), Dr. Lesley Degner, (University of Manitoba), and Dr. Harvey Chochinov (University of Manitoba). Conclusions: Citation analysis is useful for examining the research performance of psycho-oncology and supportive care researchers and identifying leaders among the

    A Delayed Discovery

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    June Potash details the story of her discovery of a previously unknown calling cards and letters, including one to Maunsell Field signed by Abraham Lincoln, found after searching a house she purchased in Cazenovia, New York

    Separable mechanisms underlying global feature-based attention

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    Feature-based attention is known to operate in a spatially global manner, in that the selection of attended features is not bound to the spatial focus of attention. Here we used electromagnetic recordings in human observers to characterize the spatiotemporal signature of such global selection of an orientation feature. Observers performed a simple orientation-discrimination task while ignoring task-irrelevant orientation probes outside the focus of attention. We observed that global feature-based selection, indexed by the brain response to unattended orientation probes, is composed of separable functional components. One such component reflects global selection based on the similarity of the probe with task-relevant orientation values ("template matching"), which is followed by a component reflecting selection based on the similarity of the probe with the orientation value under discrimination in the focus of attention ("discrimination matching"). Importantly, template matching occurs at similar to 150 ms after stimulus onset, similar to 80 ms before the onset of discrimination matching. Moreover, source activity underlying template matching and discrimination matching was found to originate from ventral extrastriate cortex, with the former being generated in more anterolateral and the latter in more posteromedial parts, suggesting template matching to occur in visual cortex higher up in the visual processing hierarchy than discrimination matching. We take these observations to indicate that the population-level signature of global feature-based selection reflects a sequence of hierarchically ordered operations in extrastriate visual cortex, in which the selection based on task relevance has temporal priority over the selection based on the sensory similarity between input representations

    A Dissociation of Attention and Awareness in Phase-sensitive but Not Phase-insensitive Visual Channels

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    The elements most vivid in our conscious awareness are the ones to which we direct our attention. Scientific study confirms the impression of a close bond between selective attention and visual awareness, yet the nature of this association remains elusive. Using visual afterimages as an index, we investigate neural processing of stimuli as they enter awareness and as they become the object of attention. We find evidence of response enhancement accompanying both attention and awareness, both in the phase-sensitive neural channels characteristic of early processing stages and in the phase-insensitive channels typical of higher cortical areas. The effects of attention and awareness on phase-insensitive responses are positively correlated, but in the same experiments, we observe no correlation between the effects on phase-sensitive responses. This indicates independent signatures of attention and awareness in early visual areas yet a convergence of their effects at more advanced processing stages
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