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The frequency of visual gamma oscillations is determined by both the neuronal excitation-inhibition balance and the time constants of GABAergic processes. The gamma peak frequency has been linked to sensory processing, cognitive function, cortical structure, and may have a genetic contribution. To disentangle the intricate relationship among these factors, accurate and reliable estimates of peak frequency are required. Here, a bootstrapping approach that provides estimates of peak frequency reliability, thereby increasing the robustness of the inferences made on this parameter was developed. The method using both simulated data and real data from two previous pharmacological MEG studies of visual gamma with alcohol and tiagabine was validated. In particular, the study by Muthukumaraswamy et al. [] (Neuropsychopharmacology 38(6):1105-1112), in which GABAergic enhancement by tiagabine had previously demonstrated a null effect on visual gamma oscillations, contrasting with strong evidence from both animal models and very recent human studies was re-evaluated. After improved peak frequency estimation and additional exclusion of unreliably measured data, it was found that the GABA reuptake inhibitor tiagabine did produce, as predicted, a marked decrease in visual gamma oscillation frequency. This result demonstrates the potential impact of objective approaches to data quality control, and provides additional translational evidence for the mechanisms of GABAergic transmission generating gamma oscillations in humans. Hum Brain Mapp 37:3882-3896, 2016. © 2016 Wiley Periodicals, Inc., (© 2016 The Authors Human Brain Mapping Published by Wiley Periodicals, Inc.)

Background: Helicobacter pylori (H pylori) is the main cause of peptic ulcer disease. The role of H pylori in non-ulcer dyspepsia is less clear., Objectives: To determine the effect of H pylori eradication on dyspepsia symptoms in patients with non-ulcer dyspepsia., Search Strategy: Trials were identified through electronic searches of the Cochrane Controlled Trials Register (CCTR), MEDLINE, EMBASE, CINAHL and SIGLE, using appropriate subject headings and keywords, searching bibliographies of retrieved articles, and through contacts with experts in the fields of dyspepsia and with pharmaceutical companies., Selection Criteria: All parallel group randomised controlled trials (RCTs) comparing drugs to eradicate H pylori with placebo or other drugs known not to eradicate H pylori for patients with non-ulcer dyspepsia., Data Collection and Analysis: Data were collected on individual and global dyspeptic symptom scores, quality of life measures and adverse effects. Dyspepsia outcomes were dichotomised into minimal/resolved versus same/worse symptoms., Main Results: Twenty one randomised controlled trials were included in the systematic review. Eighteen trials compared antisecretory dual or triple therapy with placebo antibiotics +/- antisecretory therapy, and evaluated dyspepsia at 3-12 months. Seventeen of these trials gave results as dichotomous outcomes evaluating 3566 patients and there was no significant heterogeneity between the studies. There was a 10% relative risk reduction in the H pylori eradication group (95% CI = 6% to 14%) compared to placebo. The number needed to treat to cure one case of dyspepsia = 14 (95% CI = 10 to 25). A further three trials compared Bismuth based H pylori eradication with an alternative pharmacological agent. These trials were smaller and had a shorter follow-up but suggested H pylori eradication was more effective than either H2 receptor antagonists or sucralfate in treating non-ulcer dyspepsia., Authors' Conclusions: H pylori eradication therapy has a small but statistically significant effect in H pylori positive non-ulcer dyspepsia. An economic model suggests this modest benefit may still be cost-effective but more research is needed.