SummaryBackgroundSleep difficulties might be a contributory causal factor in the occurrence of mental health problems. If this is true, improving sleep should benefit psychological health. We aimed to determine whether treating insomnia leads to a reduction in paranoia and hallucinations.MethodsWe did this single-blind, randomised controlled trial (OASIS) at 26 UK universities. University students with insomnia were randomly assigned (1:1) with simple randomisation to receive digital cognitive behavioural therapy (CBT) for insomnia or usual care, and the research team were masked to the treatment. Online assessments took place at weeks 0, 3, 10 (end of therapy), and 22. The primary outcome measures were for insomnia, paranoia, and hallucinatory experiences. We did intention-to-treat analyses. The trial is registered with the ISRCTN registry, number ISRCTN61272251.FindingsBetween March 5, 2015, and Feb 17, 2016, we randomly assigned 3755 participants to receive digital CBT for insomnia (n=1891) or usual practice (n=1864). Compared with usual practice, the sleep intervention at 10 weeks reduced insomnia (adjusted difference 4·78, 95% CI 4·29 to 5·26, Cohen's d=1·11; p<0·0001), paranoia (−2·22, −2·98 to −1·45, Cohen's d=0·19; p<0·0001), and hallucinations (−1·58, −1·98 to −1·18, Cohen's d=0·24; p<0·0001). Insomnia was a mediator of change in paranoia and hallucinations. No adverse events were reported.InterpretationTo our knowledge, this is the largest randomised controlled trial of a psychological intervention for a mental health problem. It provides strong evidence that insomnia is a causal factor in the occurrence of psychotic experiences and other mental health problems. Whether the results generalise beyond a student population requires testing. The treatment of disrupted sleep might require a higher priority in mental health provision.FundingWellcome Trust.

HighlightsWe discuss ‘inner speech’ theories of auditory verbal hallucinations.Atypical self-monitoring may lead to the experience of inner speech as external.We summarize research into the use of neurostimulation to treat hallucinations.Effects of neurostimulation may be due to modulation of self-monitoring networks.

Recent therapeutic approaches to auditory verbal hallucinations (AVH) exploit the person-like qualities of voices. Little is known, however, about how, why, and when AVH become personified. We aimed to investigate personification in individuals’ early voice-hearing experiences. We invited Early Intervention in Psychosis (EIP) service users aged 16–65 to participate in a semistructured interview on AVH phenomenology. Forty voice-hearers (M = 114.13 days in EIP) were recruited through 2 National Health Service trusts in northern England. We used content and thematic analysis to code the interviews and then statistically examined key associations with personification. Some participants had heard voices intermittently for multiple years prior to clinical involvement (M = 74.38 months), although distressing voice onset was typically more recent (median = 12 months). Participants reported a range of negative emotions (predominantly fear, 60%, 24/40, and anxiety, 62.5%, 26/40), visual hallucinations (75%, 30/40), bodily states (65%, 25/40), and “felt presences” (52.5%, 21/40) in relation to voices. Complex personification, reported by a sizeable minority (16/40, 40%), was associated with experiencing voices as conversational (odds ratio [OR] = 2.56) and companionable (OR = 3.19) but not as commanding or trauma-related. Neither age of AVH onset nor time since onset related to personification. Our findings highlight significant personification of AVH even at first clinical presentation. Personified voices appear to be distinguished less by their intrinsic properties, commanding qualities, or connection with trauma than by their affordances for conversation and companionship.

Despite the recent proliferation of scientific, clinical, and narrative accounts of auditory verbal hallucinations (AVHs), the phenomenology of voice hearing remains opaque and undertheorized. In this article, we outline an interdisciplinary approach to understanding hallucinatory experiences which seeks to demonstrate the value of the humanities and social sciences to advancing knowledge in clinical research and practice. We argue that an interdisciplinary approach to the phenomenology of AVH utilizes rigorous and context-appropriate methodologies to analyze a wider range of first-person accounts of AVH at 3 contextual levels: (1) cultural, social, and historical; (2) experiential; and (3) biographical. We go on to show that there are significant potential benefits for voice hearers, clinicians, and researchers. These include (1) informing the development and refinement of subtypes of hallucinations within and across diagnostic categories; (2) “front-loading” research in cognitive neuroscience; and (3) suggesting new possibilities for therapeutic intervention. In conclusion, we argue that an interdisciplinary approach to the phenomenology of AVH can nourish the ethical core of scientific enquiry by challenging its interpretive paradigms, and offer voice hearers richer, potentially more empowering ways to make sense of their experiences.