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ABSTRACTSentence generation involves selecting the right words out of multiple co-activated representations for the right utterance positions. This selection process is hypothesized to involve cognitive control. Previous research has linked cognitive control during language processing to regions within the frontal lobe, including the anterior cingulate cortex (ACC) and left ventrolateral prefrontal cortex (VLPFC). We examined the neural correlates of word and sentence generation to determine whether these cognitive control regions were activated more for sentences than words. We also manipulated the phonological overlap between nouns in the sentence to determine whether cognitive control recruitment increased under phonological competition. Whole-brain analysis revealed increased activation in the ACC and bilateral frontal cortex for sentences over words. Region of interest analysis revealed an effect of phonological competition within the ACC. Psychophysiological interaction (PPI) analysis further showed that functional connectivity within a task-maintenance network increased under phonological competition. These results suggest a role for conflict detection and monitoring during sentence generation, which is consistent with a theoretical framework incorporating domain-general cognitive control processes into language processing.

Blood pressure shows an inverse association with mortality in patients with chronic kidney disease (CKD) on dialysis. It is unclear if the same phenomenon exists in patients with CKD not yet on dialysis.

Significant mortality occurs in populations with chronic kidney disease (CKD), but the relative contributions of lower glomerular filtration rate (GFR) itself, accompanying comorbidities, and the numerous abnormalities that develop with advancing CKD are poorly studied. We examined all-cause predialysis mortality in 861 United States veterans with CKD stage 3 to 5 not yet on dialysis. The association of GFR with mortality was analyzed by the Kaplan-Meier method, and the effects of several confounding variables on mortality were assessed in a Cox proportional-hazards model. Overall death rate was 102.1/1,000 person-years (95% CI: 90.2 to 115.6). Lower kidney function was associated with higher mortality (relative risk [95%CI] for GFR less than 20 v41 to 60 mL/min/1.73m2: 2.56 [1.61 to 4.07], P< 0.001) after adjustment for age, race, diabetes mellitus, cardiovascular disease, smoking status, body mass index, mean arterial pressure, serum albumin, blood cholesterol, haemoglobin, and 24-hour urine protein. For every 10 mL/min/1.73m2lower estimated GFR, the adjusted relative risk of mortality (95% CI) was 1.28 (1.12 to 1.45), P< 0.001. Lower kidney function is associated with increased mortality in patients with moderate and advanced CKD. This association is present even after adjustment for several confounders.