Sleep, obesity and cardiometabolic disease in children and adolescents

© 2019 Elsevier Inc. All rights reserved. Obesity and type 2 diabetes mellitus was previously limited to adults, but in recent decades, there has been an increased prevalence among children and adolescents. Given the cost burden and a plethora of adverse consequences with which these diseases are associated, obesity and cardiometabolic diseases now pose a major public health challenge. Obesity and type 2 diabetes mellitus are chronic conditions that commonly track into adulthood and also increase the likelihood of cardiovascular consequences. While these diseases can be caused by genetics, they are largely driven by lifestyle behaviors. Attempts at addressing the global epidemic have targeted behavior modification such as increasing physical activity levels and controlling dietary intake in the hope of restoring energy balance. Sleep impinges on both side of the energy balance equation and there is now an abundance of evidence to suggest that multiple features of sleep may be contributing to the onset and progression of these chronic conditions, which are discussed in this chapter. In particular, we discuss the literature pertaining to the relationship between sleep and obesity as well as type 2 diabetes mellitus in children and adolescents, while also drawing upon crucial information from adult studies. We also highlight potential mechanisms and make recommendations for future approaches which may enhance the effectiveness of interventions targeting the global epidemic of childhood obesity, which is the main driver of metabolic and cardiovascular diseases

ICAR: endoscopic skull‐base surgery

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Attentional Networks as Predictors of Treatment Outcome in Adolescents with MDD

This research was supported by the Undergraduate Research Opportunities Program (UROP).Ozturk, Sekine. (2015). Attentional Networks as Predictors of Treatment Outcome in Adolescents with MDD. Retrieved from the University Digital Conservancy, https://hdl.handle.net/11299/171795

Perceptual Thresholds for Threat Are Lowered in Anxiety: Evidence from Perceptual Psychophysics

Anxiety is believed to be characterized by heightened sensitivity to threat. The Behavior Inhibition System (BIS), a risk factor for anxiety, is hypothesized to index this threat sensitivity. The present study addresses a critical gap in the literature: Neither anxiety nor BIS have been clearly linked with greater threat sensitivity indexed by lowered perceptual thresholds. Here, we utilized psychophysical methods to precisely measure absolute perceptual thresholds for detection of threatening and neutral faces. We examined their relationships with self-reported BIS and anxious apprehension in individuals diagnosed with and without anxiety disorders. Irrespective of anxiety disorder diagnosis, higher self-reported BIS and anxious apprehension were associated with reduced perceptual thresholds for threatening versus neutral stimuli. BIS mediated the relationship between anxiety and lowered thresholds. Using adaptive psychometrics, this study offers key empirical evidence for current theories regarding greater threat sensitivity in anxiety and clarifies the role of BIS as a mediating mechanism

Perceptual decision-making regarding phylogenetically salient stimuli

Phylogenetically salient stimuli such as spiders are commonly reported threats in the general population and the most common object of specific phobias in clinical populations. Several theories have hypothesized that our perceptual systems prioritize such stimuli in an “automatic” or “bottom-up” manner due to their evolutionary salience. However, empirical research on perceptual processing of these stimuli as well as the influence of “top-down” goal-driven and bottom-up stimulus-driven factors is lacking. Here, we used perceptual psychophysics to determine absolute perceptual thresholds for detection of spider and crab images. Subsequently, participants used spider and crab cues (that imposed a top-down perceptual set) to detect spiders and crab images presented at their predetermined perceptual threshold in a two-alternative forced-choice perceptual decision making task. While spiders were detected at lower perceptual thresholds than crabs, they were not immune to top-down influence. Indeed, compared to top-down crab cues, spider cues improved the speed and accuracy of detection of spiders vs crabs. Using a hierarchical drift diffusion model, we found that spider cues biased decision-making not only by shifting the starting point of evidence accumulation towards the spider decision, but also by increasing the efficiency with which sensory evidence accumulated, more so for spider than crab perceptual decisions. Overall, these findings provide evidence for perceptual prioritization of phylogenetically salient stimuli and highlight the computational mechanisms by which this prioritization is facilitated by bottom-up and top-down factors

Knowledge of threat biases perceptual decision-making in anxiety: Evidence from signal detection theory and drift diffusion modeling

Background. Threat biases are considered key factors in the development and maintenance of anxiety. Yet, these biases are poorly operationalized and remain unquantified. Furthermore, it is unclear whether and how prior knowledge of threat and its uncertainty induce these biases and how they manifest in anxiety. Method. Participants (n=55) used prestimulus cues to decide whether the subsequently presented stimuli were threatening or neutral. The cues either provided no information about the probability (high uncertainty) or indicated high probability (low uncertainty) of encountering threatening or neutral targets. We used signal detection theory (SDT) and hierarchical drift diffusion model (HDDM) to quantify bias. Results. High uncertainty threat cues improved discrimination of subsequent threatening and neutral stimuli more than the neutral cues. However, anxiety was associated with worse discrimination of threatening versus neutral stimuli following high uncertainty threat cues. Using HDDM, we found that threat cues biased decision-making not only by shifting the starting point of evidence accumulation towards the threat decision, but also by increasing the efficiency with which sensory evidence was accumulated for both threat-related and neutral decisions. However, higher anxiety was associated with a greater shift of starting point towards the threat decision, but not with the efficiency of evidence accumulation. Conclusions. Using computational modeling, these results highlight the biases by which knowledge regarding uncertain threat improves perceptual decision-making but impairs it in case of anxiety

Hippocampal Subregions Across the Psychosis Spectrum

Introduction:Converging evidence suggests that hippocampal subregions subserve different functions, and are differentially affected by psychosis illness progression. Despite this fact, studies have not often studied subregions cross-sectionally across the psychosis spectrum. Furthermore, little is known about associations between subregion volumes and hippocampus-mediated cognition. Methods:A total of 222 participants (61 ultra high risk [UHR], 91 schizophrenia [SCZ], and 70 healthy volunteers) underwent a 3T MRI scan, as well as structured clinical interviews and a cognitive battery. Hippocampal subfield analysis was conducted with Freesurfer. We compared subregion volumes across groups, controlling for age, gender, and intracranial volume. We also examined associations in the UHR and SCZ groups between hippocampal subregion volumes and verbal learning, visual learning, and working memory. Results:We found a dose-dependent relationship such that the SCZ group showed significantly greater subfield volume reductions than the UHR group, which in turn showed significantly greater subfield volume reductions than the healthy volunteer group. We also found associations between subregion volume and cognitive performance in the visual memory, verbal memory, and working memory domains. Discussion:Our study examined hippocampal subregion volumes cross-sectionally in a large sample across the psychosis spectrum, as well as links with hippocampus-mediated cognitive function. Our findings suggest that hippocampal abnormalities emerge before first psychosis episode onset, and may be etiologically informative