Melatonin is a physiological hormone involved in sleep timing and is currently used exogenously in the treatment of primary and secondary sleep disorders with empirical evidence of efficacy, but very little evidence from randomised, controlled studies. The aim of this meta-analysis was to assess the evidence base for the therapeutic effects of exogenous melatonin in treating primary sleep disorders. An electronic literature review search of MEDLINE (1950-present) EMBASE (1980- present), PsycINFO (1987- present), and SCOPUS (1990- present), along with a hand-searching of key journals was performed in July 2013 and then again in May 2015. This identified all studies that compared the effect of exogenous melatonin and placebo in patients with primary insomnia, delayed sleep phase syndrome, Non 24- hour sleep wake syndrome in people who are blind, and REM-Behaviour Disorder. Meta-analyses were performed to determine the effect of magnitude in studies of melatonin in improving sleep. A total of 5030 studies were identified; of these citations, 13 were included for review based on the inclusion criteria of being: double or single-blind, randomised and controlled. Results from the meta-analyses showed the most convincing evidence for exogenous melatonin use was in reducing sleep onset latency in primary insomnia (p=0.002), delayed sleep phase syndrome (p<0.0001), and regulating the sleepwake patterns in blind patients compared with placebo. These findings highlight the potential importance of melatonin in treating certain first degree sleep disorders. The development of large-scale, randomised, controlled trials is recommended to provide further evidence for therapeutic use of melatonin in a variety of sleep difficulties

Recognizing emotional expressions is central to understanding the feelings and intentions of other people. Little is known about how social anxiety affects the recognition of emotional expressions. Recent research finds a recognition advantage for happy expressions over negative expressions. In two experiments, social anxiety moderated the recognition advantage of happy faces. People low and high in social anxiety recognized sad faces (Experiment 1) and angry faces (Experiment 2) equally quickly, but people high in social anxiety took longer to recognize happy faces. Both groups showed a significant recognition advantage for happy faces, although the advantage was at least twice as large in the low social-anxiety group. The discussion focuses on mechanisms connecting social anxiety to face processing and on the role of expression recognition in other emotionalprocessing biases.

ALH and HVC (Grant number: L-023032) is registered at ClinicalTrials.gov (ID: NCT02649231).We would furthermore like to thank Dr. Evgeny Krupitsky for his pioneering research into ketamine as a treatment and his input into the design of the study. This paper is dedicated to the memory of our colleague Dr. David Gilhooly.

BackgroundNarcolepsy is a chronic primary sleep disorder, characterized by excessive daytime sleepiness and sleep dysfunction with or without cataplexy. Narcolepsy is uncommon, with a low prevalence rate which makes it difficult to diagnose definitively without a complex series of tests and a detailed history. The aim of this study was to review patients referred to a tertiary sleep centre who had been labelled with a diagnosis of narcolepsy prior to referral in order to assess if the diagnosis was accurate, and if not, to determine the cause of diagnostic misattribution.MethodsAll patients seen at a sleep centre from 2007–2013 (n = 551) who underwent detailed objective testing including an MSLT PSG, as well as wearing an actigraphy watch and completing a sleep diary for 2 weeks, were assessed for a pre-referral and final diagnosis of narcolepsy.ResultsOf the 41 directly referred patients with a diagnostic label of narcolepsy, 19 (46 %) were subsequently confirmed to have narcolepsy on objective testing and assessment by a sleep physician using ICSD-2 criteria.ConclusionsThe diagnosis of narcolepsy was incorrectly attributed to almost 50 % of patients labelled with a diagnosis of narcolepsy who were referred for further opinion by a variety of specialists and generalists. Accurate diagnosis of narcolepsy is critical for many reasons, such as the impact it has on quality of life, driving, employment, insurance and pregnancy in women as well as medication management.