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Amiez C  Sallet J  Procyk E  Petrides M 《NeuroImage》2012,63(3):1078-1090
The present functional magnetic resonance imaging (fMRI) experiment aims at clarifying the role of the rostral anterior cingulate cortex (rACC) in the evaluation of feedback in a deterministic environment. We tested, in particular, the response of the rACC to the detection of different types of feedback, and to varying levels of outcome expectancy. We used a problem-solving task in which subjects had to discover, in successive trials, which one of the four presented stimuli was associated with a positive feedback, the other ones being associated with error feedback. In this task, two periods alternated: 1. an exploratory period in which error feedback indicated to adapt the following response appropriately (and continue to explore), and first positive feedback indicated to change strategy (i.e. to shift from explorative to exploitative behavior), and 2. an exploitative period in which subjects had to repeat the correct choice. The rACC is recruited in the exploratory period during the analysis of both error and first correct positive feedback. In addition, the rACC activity was modulated by positive reward prediction error values (i.e. the difference between obtained and expected feedback). Altogether, these results reveal the critical role of the rACC in the evaluation of salient feedback for learning optimal strategies.  相似文献   
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Objective: To assess the relationship between the Screen for Cognitive Impairment in Psychiatry (SCIP) score and illness severity, subjective cognition and functioning in a cohort of major depressive disorder (MDD) patients.

Methods: Patients (n?=?40) diagnosed with MDD (DSM-IV-TR) completed the SCIP, a brief neuropsychological test, and a battery of self-administered questionnaires evaluating functioning (GAF, SDS, WHODAS 2.0, EDEC, PDQ-D5). Disease severity was evaluated with the Hamilton Depression Rating Scale (HDRS) and the Clinical Global Impression (CGI).

Results: Age and sex were associated with performance in the SCIP. The SCIP-Global index score was associated with disease severity (r?=??0.316, p?<?.05), the SDS, a patient self-assessment of daily functioning (r?=??0.368, p?<?.05), and the EDEC subscales of patient-reported cognitive deficits (r?=??0.388, p?<?.05) and their functional impacts (r?=??0.335, p?<?.05). Multivariate analysis adjusted for age and sex confirmed these tests are independent predictors of performance in the SCIP (CGI-S, F[3,34]?=?4.478, p?=?.009; SDS, F[3,34]?=?3.365, p?=?.030; EDEC-perceived cognitive deficits, F[3,34]?=?5.216, p?=?.005; EDEC-perceived impacts of functional impairment, F[3,34]?=?5.154, p?=?.005).

Conclusions: This study confirms that the SCIP can be used during routine clinical evaluation of MDD, and that cognitive deficits objectively assessed in the SCIP are associated with disease severity and self-reported cognitive dysfunction and impairment in daily life.  相似文献   

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Maternal and Child Health Journal - Low birth weight is a public health issue that contributes to perinatal and infant mortality, especially in limited-resource settings, but there is limited...  相似文献   
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Burkitt lymphoma (BL) occurs at all ages, but the patterns of Epstein–Barr virus (EBV) positivity in relation to human immunodeficiency virus (HIV), immunoprofiles and age have not been fully explored. BL tissues from residual tissue repositories, and two academic centers in the United States were examined by expert hematopathologists for morphology, immunohistochemistry, MYC rearrangement, EBV‐encoded RNA (EBER), and diagnosed according to the 2008 WHO lymphoma classification. Analysis was done using frequency tables, Chi‐squared statistics, and Student's t‐test. Of 117 cases examined, 91 were confirmed as BL. The age distribution was 26%, 15%, 19%, and 29% for 0–19, 20–34, 35–59, 60+ years, and missing in 11%. MYC rearrangement was found in 89% and EBER positivity in 29% of 82 cases with results. EBER positivity varied with age (from 13% in age group 0–19 to 55% in age group 20–34, and fell to 25% in age group 60+ years, p = 0.08); with race (56% in Blacks/Hispanics vs 21% in Whites/Asians/Pacific Islanders, p = 0.006); and by HIV status (64% in HIV positive vs 22% in HIV negative cases, p = 0.03). EBER positivity was demonstrated in about one‐third of tumors and it was strongly associated with race and HIV status, and marginally with age‐group.  相似文献   
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