265 research outputs found

    Frontal white matter tracts sustaining speech production in primary progressive aphasia

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    In primary progressive aphasia (PPA), speech and language difficulties are caused by neurodegeneration of specific brain networks. In the nonfluent/agrammatic variant (nfvPPA), motor speech and grammatical deficits are associated with atrophy in a left fronto-insular-striatal network previously implicated in speech production. In vivo dissection of the crossing white matter (WM) tracts within this "speech production network" is complex and has rarely been performed in health or in PPA. We hypothesized that damage to these tracts would be specific to nfvPPA and would correlate with differential aspects of the patients' fluency abilities. We prospectively studied 25 PPA and 21 healthy individuals who underwent extensive cognitive testing and 3 T MRI. Using residual bootstrap Q-ball probabilistic tractography on high angular resolution diffusion-weighted imaging (HARDI), we reconstructed pathways connecting posterior inferior frontal, inferior premotor, insula, supplementary motor area (SMA) complex, striatum, and standard ventral and dorsal language pathways. We extracted tract-specific diffusion tensor imaging (DTI) metrics to assess changes across PPA variants and perform brain-behavioral correlations. Significant WM changes in the left intrafrontal and frontostriatal pathways were found in nfvPPA, but not in the semantic or logopenic variants. Correlations between tract-specific DTI metrics with cognitive scores confirmed the specific involvement of this anterior-dorsal network in fluency and suggested a preferential role of a posterior premotor-SMA pathway in motor speech. This study shows that left WM pathways connecting the speech production network are selectively damaged in nfvPPA and suggests that different tracts within this system are involved in subcomponents of fluency. These findings emphasize the emerging role of diffusion imaging in the differential diagnosis of neurodegenerative diseases

    Short-term prognosis of breakthrough venous thromboembolism in anticoagulated patients

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    Background: Evidence for guideline recommendations for the treatment of venous thromboembolism (VTE) during anticoagulant therapy is scarce. We aimed to observe and to describe the management of VTE occurring during anticoagulant therapy. Methods: This prospective multi-center, observational study included patients with objectively confirmed VTE during anticoagulant therapy (breakthrough event), with a follow-up of 3 months, after the breakthrough event. Results: We registered 121 patients with a breakthrough event, with a mean age of 56 years (range, 19 to 90); 61 were male (50%). Fifty-eight patients (48%) had an active malignancy. At the time of the breakthrough event, 57 patients (47%) were treated with a vitamin K antagonist (VKA), 53 patients (44%) with low-molecular-weight heparin (LMWH) and 11 patients (9%) with direct oral anticoagulants, unfractionated heparin, or VKA plu

    School sector variation on non-cognitive dimensions: are denominational schools different?

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    Denominational schooling makes up an important part of European educational systems. Given its specificity, denominational schooling can be expected to place a greater weight on values teaching and moral education. As such, it may be more effective in bringing about certain attitudes and opinions. It also may be more successful in creating a warm and caring atmosphere, thus helping students to better emotionally connect to the school community. This paper set out to empirically test some of these hypotheses by making use of three waves of data collected in the framework of the Program for International Student Assessment study. We compare public and publicly supported private (as a proxy to denominational) schools on two dimensions, namely the emotional integration with the rest of the school community, and the concern and feelings of responsibility towards the environment. But for Austria, Belgium and Spain, no evidence could be found that the type of the school has any impact on the reported psychological adaptation to the school. In these three countries, publicly supported private schools tend to be more successful in integrating their students. Also students in public and private dependent schools were equally environment oriented, taking into account several student and school characteristics. The lack of schooling sector differences in attaining non-cognitive aims may have at least three causes. First, ecological issues could be salient enough not to necessitate any special religious or moral reinforcement in order to gain traction. Second, public schools may use religious education or ethics just as fruitfully and consequently, they are just as successful in values and norms transmission. Third, it is possible that schools play a minor role in introducing students to environmental dilemmas and concerns, this role being taken over by the family or the media

    A large-scale examination of the effectiveness of anonymous marking in reducing group performance differences in higher education assessment

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    The present research aims to more fully explore the issues of performance differences in higher education assessment, particularly in the context of a common measure taken to address them. The rationale for the study is that, while performance differences in written examinations are relatively well researched, few studies have examined the efficacy of anonymous marking in reducing these performance differences, particularly in modern student populations. By examining a large archive (N = 30674) of assessment data spanning a twelve-year period, the relationship between assessment marks and factors such as ethnic group, gender and socio-environmental background was investigated. In particular, analysis focused on the impact that the implementation of anonymous marking for assessment of written examinations and coursework has had on the magnitude of mean score differences between demographic groups of students. While group differences were found to be pervasive in higher education assessment, these differences were observed to be relatively small in practical terms. Further, it appears that the introduction of anonymous marking has had a negligible effect in reducing them. The implications of these results are discussed, focusing on two issues, firstly a defence of examinations as a fair and legitimate form of assessment in Higher Education, and, secondly, a call for the re-examination of the efficacy of anonymous marking in reducing group performance differences
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