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Previous work suggests that sleep disruption can contribute to poor pain modulation. Here, we used experimental sleep disruption to examine the relationship between sleep disruption-induced pain sensitivity and functional connectivity (FC) of cognitive networks contributing to pain modulation. Nineteen healthy individuals underwent two counterbalanced experimental sleep conditions for one night each: uninterrupted sleep versus sleep disruption. Following each condition, participants completed functional MRI including a simple motor task and a noxious thermal stimulation task. Pain ratings and stimulus temperatures from the latter task were combined to calculate a pain sensitivity change score following sleep disruption. This change score was used as a predictor of simple motor task FC changes using bilateral executive control networks (RECN, LECN) and the default mode network (DMN) masks as seed regions of interest (ROIs). Increased pain sensitivity after sleep disruption was positively associated with increased RECN FC to ROIs within the DMN and LECN (F(4,14) = 25.28, pFDR = 0.05). However, this pain sensitivity change score did not predict FC changes using LECN and DMN masks as seeds (pFDR > 0.05). Given that only RECN FC was associated with sleep loss-induced hyperalgesia, findings suggest that cognitive networks only partially contribute to the sleep-pain dyad.

Westergaard's microcue account raises the question of the exact nature of language transfer in the acquisition of languages as well of how L1/Ln input interacts with the principles of universal grammar (UG) during processing. In order to consider in more detail the actual representation building, processing mechanisms that would be involved, her approach will be spelled out in terms of the Modular Cognition Framework (see Sharwood Smith, 2017; Sharwood Smith and Truscott, 2014; Truscott and Sharwood Smith, 2004, 2019). As well as identifying the way in which microcues would be constructed, this analysis in particular will have the effect of undermining the concept underlying the transfer metaphor as a way of characterizing crosslinguistic influence.

A significantly higher proportion of patients with nonalcoholic steatohepatitis (NASH) who received obeticholic acid (OCA) had histological improvement relative to placebo in the FLINT (farnesoid X nuclear receptor ligand obeticholic acid for noncirrhotic, NASH treatment) trial. However, genetic predictors of response to OCA are unknown. We conducted a genome-wide association study (GWAS) in FLINT participants to identify variants associated with NASH resolution and fibrosis improvement. Genotyping was performed using the Omni2.5 content GWAS chip. To avoid false positives introduced by population stratification, we focused our GWAS on white participants. Six regions on chromosomes 1, 4, 6, 7, 15, and 17 had multiple single nucleotide polymorphisms (SNPs) with suggestive association (P

ObjectiveClassification of epilepsy into types and subtypes is important for both clinical care and research into underlying disease mechanisms. A quantitative, data-driven approach may augment traditional electroclinical classification and shed new light on existing classification frameworks.MethodsWe used latent class analysis, a statistical method that assigns subjects into groups called latent classes based on phenotypic elements, to classify individuals with common familial epilepsies from the Epi4K Multiplex Families study. Phenotypic elements included seizure types, seizure symptoms, and other elements of the medical history. We compared class assignments to traditional electroclinical classifications and assessed familial aggregation of latent classes.ResultsA total of 1120 subjects with epilepsy were assigned to five latent classes. Classes 1 and 2 contained subjects with generalized epilepsy, largely reflecting the distinction between absence epilepsies and younger onset (class 1) versus myoclonic epilepsies and older onset (class 2). Classes 3 and 4 contained subjects with focal epilepsies, and in contrast to classes 1 and 2, these did not adhere as closely to clinically defined focal epilepsy subtypes. Class 5 contained nearly all subjects with febrile seizures plus or unknown epilepsy type, as well as a few subjects with generalized epilepsy and a few with focal epilepsy. Family concordance of latent classes was similar to or greater than concordance of clinically defined epilepsy types.SignificanceQuantitative classification of epilepsy has the potential to augment traditional electroclinical classification by (1) combining some syndromes into a single class, (2) splitting some syndromes into different classes, (3) helping to classify subjects who could not be classified clinically, and (4) defining the boundaries of clinically defined classifications. This approach can guide future research, including molecular genetic studies, by identifying homogeneous sets of individuals that may share underlying disease mechanisms.

Background & aimsNoninvasive methods are needed to determine disease stage in patients with nonalcoholic fatty liver disease (NAFLD). We evaluated the diagnostic performance of several widely available fibrosis models for the assessment of hepatic fibrosis in patients with NAFLD.MethodsWe performed a retrospective analysis of data from individuals enrolled in the NIDDK NASH Clinical Research Network, from 2004 through 2018. Using biopsy as the reference standard, we determined the diagnostic performance of the aspartate aminotransferase (AST):platelet ratio (APRI), FIB-4, ratio of AST:alanine aminotransferase (ALT) and the NAFLD fibrosis score (NFS) in a cross-sectional study of 1904 subjects. The ability of these models to detect changes in fibrosis stage was assessed in a longitudinal data set of 292 subjects with 2 biopsies and accompanying laboratory data. Outcomes were detection of fibrosis of any stage (stages 0-4), detection of moderate fibrosis (stages 0-1 vs 2-4), and detection of advanced fibrosis (stages 0-2 vs 3-4). Diagnostic performance was evaluated using the C-statistic, sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) analyses.ResultsIn the cross-sectional study, FIB-4 and NFS outperformed other non-invasive models for detecting advanced fibrosis; the C-statistics were 0.80 for FIB-4 and 0.78 for NFS. In the longitudinal study, 216 patients had non-advanced fibrosis at baseline and 35 patients progressed to advanced fibrosis after median follow up of 2.6 years. After we adjusted for fibrosis stage and model score at initial biopsy, change in APRI, FIB-4, and NFS were significantly associated with change in fibrosis. A unit change in APRI, FIB-4, or NFS was associated with changes in fibrosis stage of 0.33 (95% CI, 0.20-0.45; P < .001), 0.26 (95% CI, 0.15-0.37; P < .001), and 0.19 (95% CI, 0.07-0.31; P = .002), respectively. The cross-validated C-statistic for detecting progression to advanced fibrosis for APRI was 0.82 (95% CI, 0.74-0.89), for FIB-4 was 0.81 (95% CI, 0.73-0.81), and for NFS was 0.80 (95% CI, 0.71-0.88).ConclusionsIn a combined analysis of data from 2 large studies, we found that FIB-4, APRI, and NFS can detect advanced fibrosis and fibrosis progression in patients with NAFLD.

The nucleus accumbens (NAc) has been implicated in sleep, reward, and pain modulation, but the relationship between these functional roles is unclear. This study aimed to determine whether NAc function at the onset and offset of a noxious thermal stimulus is enhanced by rewarding music, and whether that effect is reversed by experimental sleep disruption. Twenty-one healthy subjects underwent functional magnetic resonance imaging scans on 2 separate days after both uninterrupted sleep and experimental sleep disruption. During functional magnetic resonance imaging scans, participants experienced noxious stimulation while listening to individualized rewarding or neutral music. Behavioral results revealed that rewarding music significantly reduced pain intensity compared with neutral music, and disrupted sleep was associated with decreased pain intensity in the context of listening to music. In whole-brain family-wise error cluster-corrected analysis, the NAc was activated at pain onset, but not during tonic pain or at pain offset. Sleep disruption attenuated NAc activation at pain onset and during tonic pain. Rewarding music altered NAc connectivity with key nodes of the corticostriatal circuits during pain onset. Sleep disruption increased reward-related connectivity between the NAc and the anterior midcingulate cortex at pain onset. This study thus indicates that experimental sleep disruption modulates NAc function during the onset of pain in a manner that may be conditional on the presence of competing reward-related stimuli. These findings point to potential mechanisms for the interaction between sleep, reward, and pain, and suggest that sleep disruption affects both the detection and processing of aversive stimuli that may have important implications for chronic pain.

Sleep disturbances increase vulnerability for depression, but the mechanisms underlying this relationship are not well known. We investigated the effects of experimental sleep disruption on response bias (RB), a measure of reward learning previously linked to depression, and the moderating role of positive affect responses. Participants (N = 42) were healthy adults enrolled in a within-subject crossover sleep disruption experiment that incorporated one night of uninterrupted sleep (US) and one night of forced awakenings (FA) in random order. On the day following each experimental sleep night, participants completed a probabilistic reward task to assess RB, and the Positive and Negative Affect Schedule-X. Participants were subgrouped according to positive affect responses: Preserved Positive Affect (i.e. positive affect scores maintained or increased; n = 15) or Reduced Positive Affect (i.e. positive affect scores decreased; n = 27) following FA. Contrary to our hypotheses, across participants, RB did not significantly differ between the US and FA sleep conditions (p = .67). However, the effect of sleep condition on RB was moderated by positive affect response (p = .01); those with preserved positive affect showed heightened RB following FA, whereas those with reduced positive affect showed diminished RB following FA. Changes in negative affect between US and FA did not moderate RB. The inability to preserve positive affect through periods of sleep disruption may be a marker of diminished reward learning capability. Understanding how sleep disruption impacts positive affect responses and reward learning identifies a pathway by which sleep disturbances may confer risk for depression.