54 research outputs found

    Face Inversion Reduces the Persistence of Global Form and Its Neural Correlates

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    Face inversion produces a detrimental effect on face recognition. The extent to which the inversion of faces and other kinds of objects influences the perceptual binding of visual information into global forms is not known. We used a behavioral method and functional MRI (fMRI) to measure the effect of face inversion on visual persistence, a type of perceptual memory that reflects sustained awareness of global form. We found that upright faces persisted longer than inverted versions of the same images; we observed a similar effect of inversion on the persistence of animal stimuli. This effect of inversion on persistence was evident in sustained fMRI activity throughout the ventral visual hierarchy, including the lateral occipital area (LO), two face-selective visual areas—the fusiform face area (FFA) and the occipital face area (OFA)—and several early visual areas. V1 showed the same initial fMRI activation to upright and inverted forms but this activation lasted longer for upright stimuli. The inversion effect on persistence-related fMRI activity in V1 and other retinotopic visual areas demonstrates that higher-tier visual areas influence early visual processing via feedback. This feedback effect on figure-ground processing is sensitive to the orientation of the figure

    fMRI scanner noise interaction with affective neural processes

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    The purpose of the present study was the investigation of interaction effects between functional MRI scanner noise and affective neural processes. Stimuli comprised of psychoacoustically balanced musical pieces, expressing three different emotions (fear, neutral, joy). Participants (N=34, 19 female) were split into two groups, one subjected to continuous scanning and another subjected to sparse temporal scanning that features decreased scanner noise. Tests for interaction effects between scanning group (sparse/quieter vs continuous/noisier) and emotion (fear, neutral, joy) were performed. Results revealed interactions between the affective expression of stimuli and scanning group localized in bilateral auditory cortex, insula and visual cortex (calcarine sulcus). Post-hoc comparisons revealed that during sparse scanning, but not during continuous scanning, BOLD signals were significantly stronger for joy than for fear, as well as stronger for fear than for neutral in bilateral auditory cortex. During continuous scanning, but not during sparse scanning, BOLD signals were significantly stronger for joy than for neutral in the left auditory cortex and for joy than for fear in the calcarine sulcus. To the authors' knowledge, this is the first study to show a statistical interaction effect between scanner noise and affective processes and extends evidence suggesting scanner noise to be an important factor in functional MRI research that can affect and distort affective brain processes

    Representing 3D Space in Working Memory: Spatial Images from Vision, Hearing, Touch, and Language

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    The chapter deals with a form of transient spatial representation referred to as a spatial image. Like a percept, it is externalized, scaled to the environment, and can appear in any direction about the observer. It transcends the concept of modality, as it can be based on inputs from the three spatial senses, from language, and from long-term memory. Evidence is presented that supports each of the claimed properties of the spatial image, showing that it is quite different from a visual image. Much of the evidence presented is based on spatial updating. A major concern is whether spatial images from different input modalities are functionally equivalent— that once instantiated in working memory, the spatial images from different modalities have the same functional characteristics with respect to subsequent processing, such as that involved in spatial updating. Going further, the research provides some evidence that spatial images are amodal (i.e., do not retain modality-specific features)

    Species concepts and speciation factors in cyanobacteria, with connection to the problems of diversity and classification

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    Triplet chemotherapy in combination with anti-EGFR agents for the treatment of metastatic colorectal cancer: Current evidence, advances, and future perspectives

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    Doublet or triplet chemotherapy regimens in combination with anti–epidermal growth factor receptor (anti-EGFR) monoclonal antibodies (mAb), such as cetuximab or panitumumab, or the anti–vascular endothelial growth factor mAb bevacizumab, are the current recommended standard of care therapies for unresectable metastatic colorectal cancer (mCRC). While the recommended dosing schedule for the triplet chemotherapy regimen with 5-fluorouracil, oxaliplatin and irinotecan (FOLFOXIRI) in combination with bevacizumab is well established, the optimal dosing of FOLFOXIRI in combination with anti-EGFR agents is unknown. Several randomized, phase 3 clinical trials of patients with mCRC have demonstrated improved survival and response rates with FOLFOXIRI, alone or when combined with bevacizumab, compared with doublet chemotherapy regimens. Trials of anti-EGFR agents in combination with FOLFOXIRI have also shown promising results. In this review, we summarize the emerging evidence regarding the safety and efficacy of anti-EGFR agents in combination with triplet chemotherapy regimens and discuss the potential for this combination as a future treatment option for patients with RAS-wild-type mCRC

    Radiothérapie stéréotaxique hépatique : particularités cliniques et implications techniques, résultats. Quelle machine pour quelle situation ?

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    International audienceLiver stereotactic body radiotherapy is a developing technique for the treatment of primary tumours and metastases. Its implementation is complex because of the particularities of the treated organ and the comorbidities of the patients. However, this technique is a treatment opportunity for patients otherwise in therapeutic impasse. The scientific evidence of liver stereotactic body radiotherapy has been considered by the French health authority as insufficient for its widespread use outside specialized and experienced centers, despite a growing and important number of retrospective and prospective studies, but few comparative data. This article focuses on the specific features of stereotactic body radiotherapy for liver treatments and the results of published studies of liver stereotactic body radiotherapy performed with classic linear accelerators and dedicated radiosurgery units.La radiothĂ©rapie stĂ©rĂ©otaxique hĂ©patique est une technique de traitement en dĂ©veloppement pour le traitement des tumeurs primitives et secondaires. Sa mise en Ɠuvre est complexe du fait des particularitĂ©s de l’organe traitĂ© et des comorbiditĂ©s des patients. Elle reprĂ©sente cependant une opportunitĂ© de traitement efficace pour beaucoup de patients en impasse thĂ©rapeutique. Son niveau de preuve est jugĂ© insuffisant par la Haute AutoritĂ© de SantĂ© (HAS) pour une large diffusion en dehors des centres expĂ©rimentĂ©s. Il existe pourtant un nombre consĂ©quent et grandissant d’études rĂ©trospectives ou prospectives, mais peu de donnĂ©es comparatives. Cet article rĂ©sume les particularitĂ©s de la radiothĂ©rapie stĂ©rĂ©otaxique pour cette localisation et reprend les rĂ©sultats des Ă©tudes publiĂ©es pour les machines dĂ©diĂ©es et non dĂ©diĂ©es
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