The experience of felt presence in a general population sample.

Felt presence is a widely occurring experience, but remains under-recognised in clinical and research practice. To contribute to a wider recognition of the phenomenon, we aimed to assess the presentation of felt presence in a large population sample (n = 10 447) and explore its relation to key risk factors for psychosis. In our sample 1.6% reported experiencing felt presence in the past month. Felt presence was associated with visual and tactile hallucinations and delusion-like thinking; it was also associated with past occurrence of adverse events, loneliness and poor sleep. The occurrence of felt presence may function as a marker for general hallucination proneness.

Impacts of risk thresholds and age on clinical high risk for psychosis: a comparative network analysis.

One of the main goals for supporting people with a psychotic disorder is early detection and intervention, and the detection of Clinical High Risk (CHR) is a major challenge in this respect. This study sought to compare core symptoms of CHR for psychosis networks based on two CHR self-assessment tools, across different risk thresholds and age groups. This cross-sectional online investigation analyzed 936 individuals for CHR, in France and the UK, with the Prodromal Questionnaire-16 (PQ-16) and the Perceptual and Cognitive Aberrations (PCA). Twelve different symptom networks were constructed, assessing relationships, compactness, centrality, predictability, and comparisons between them, based on different thresholds and age groups. In the above-threshold PQ-16 network, the most central symptom was "Voices or whispers"; in the PCA network, the most central symptom was "Non-relevant thoughts distract or bother". They presented low overall predictability. No significant difference was found between them. This study makes three key contributions. First, this cross-network analyses highlight the relative importance of some central symptoms. Secondly, comparisons between networks demonstrate the unity of the CHR construct across scales, thresholds, and ages, affirming its phenotypic homogeneity, an essential issue for patient care pathways. Thirdly, the low average network predictability suggests the existence of unconsidered symptoms within these CHR networks. These results shed light on the organization of CHR symptoms using routine clinical questionnaires, offering insights for preventive targets in a logic of precision semiology.

Utilizing graph machine learning within drug discovery and development.

Graph machine learning (GML) is receiving growing interest within the pharmaceutical and biotechnology industries for its ability to model biomolecular structures, the functional relationships between them, and integrate multi-omic datasets - amongst other data types. Herein, we present a multidisciplinary academic-industrial review of the topic within the context of drug discovery and development. After introducing key terms and modelling approaches, we move chronologically through the drug development pipeline to identify and summarize work incorporating: target identification, design of small molecules and biologics, and drug repurposing. Whilst the field is still emerging, key milestones including repurposed drugs entering in vivo studies, suggest GML will become a modelling framework of choice within biomedical machine learning.

Varieties of felt presence? Three surveys of presence phenomena and their relations to psychopathology.

BACKGROUND: Experiences of felt presence (FP) are well documented in neurology, neuropsychology and bereavement research, but systematic research in relation to psychopathology is limited. FP is a feature of sensorimotor disruption in psychosis, hypnagogic experiences, solo pursuits and spiritual encounters, but research comparing these phenomena remains rare. A comparative approach to the phenomenology of FP has the potential to identify shared and unique processes underlying the experience across these contexts, with implications for clinical understanding and intervention. METHODS: We present a mixed-methods analysis from three online surveys comparing FP across three diverse contexts: a population sample which included people with experience of psychosis and voice-hearing (study 1, N = 75), people with spiritual and spiritualist beliefs (study 2, N = 47) and practitioners of endurance/solo pursuits (study 3, N = 84). Participants were asked to provide descriptions of their FP experiences and completed questionnaires on FP frequency, hallucinatory experiences, dissociation, paranoia, social inner speech and sleep. Data and code for the study are available via OSF. RESULTS: Hierarchical linear regression analysis indicated that FP frequency was predicted by a general tendency to experience hallucinations in all three studies, although paranoia and gender (female > male) were also significant predictors in sample 1. Qualitative analysis highlighted shared and diverging phenomenology of FP experiences across the three studies, including a role for immersive states in FP. CONCLUSIONS: These data combine to provide the first picture of the potential shared mechanisms underlying different accounts of FP, supporting a unitary model of the experience.

Hallucinations as a risk marker for suicidal behaviour in individuals with a history of sexual assault: a general population study with instant replication.

BACKGROUND: Research has shown a strong relationship between hallucinations and suicidal behaviour in general population samples. Whether hallucinations also index suicidal behaviour risk in groups at elevated risk of suicidal behaviour, namely in individuals with a sexual assault history, remains to be seen. AIMS: We assessed whether hallucinations were markers of risk for suicidal behaviour among individuals with a sexual assault history. METHODS: Using the cross-sectional 2007 (N = 7403) and 2014 (N = 7546) Adult Psychiatric Morbidity Surveys, we assessed for an interaction between sexual assault and hallucinations in terms of the odds of suicide attempt, as well as directly comparing the prevalence of suicide attempt in individuals with a sexual assault history with v. without hallucinations. RESULTS: Individuals with a sexual assault history had increased odds of hallucinations and suicide attempt compared to individuals without a sexual assault history in both samples. There was a significant interaction between sexual assault and hallucinations in terms of the odds of suicide attempt. In total, 14-19% of individuals with a sexual assault history who did not report hallucinations had one or more suicide attempt. This increased to 33-52% of individuals with a sexual assault history who did report hallucinations (2007, aOR = 2.85, 1.71-4.75; 2014, aOR = 4.52, 2.78-7.35). CONCLUSIONS: Hallucinations are a risk marker for suicide attempt even among individuals with an elevated risk of suicidal behaviour, specifically individuals with a sexual assault history. This finding highlights the clinical significance of hallucinations with regard to suicidal behaviour risk, even among high-risk populations.

Measurement practices in hallucinations research.

Introduction: In several sub-fields of psychology, there has been a renewed focus on measurement practices. As far as we are aware, this has been absent in hallucinations research. Thus, we investigated (a) cross-study variation in how hallucinatory experiences are measured and (b) the reliability of measurements obtained using two tasks that are widely employed in hallucinations research.Method: In Study 1, we investigated to what extent there was variation in how the Launay-Slade Hallucination Scale (LSHS) has been used across 100 studies. In Study 2, we investigated the reliability of the measurements obtained through source monitoring and signal detection tasks, using data from four recent publications. Materials/data are available at doi: 10.17605/osf.io/d3gnk/.Results: In Study 1, we found substantial variation in how hallucinatory experiences were assessed using the LSHS and that descriptions of the LSHS were often incomplete in important ways. In Study 2, we reported a range of reliability estimates for the measurements obtained using source monitoring and signal discrimination tasks. Some measurements obtained using source monitoring tasks had unacceptably low levels of reliability.Conclusions: Our findings suggest that suboptimal measurement practices are common in hallucinations research and we suggest steps researchers could take to improve measurement practices.

Hearing spiritually significant voices: A phenomenological survey and taxonomy.

Whereas previous research in the medical humanities has tended to neglect theology and religious studies, these disciplines sometimes have a very important contribution to make. The hearing of spiritually significant voices provides a case in point. The context, content and identity of these voices, all of which have typically not been seen as important in the assessment of auditory-verbal hallucinations (AVHs) within psychiatry, are key to understanding their spiritual significance. A taxonomy of spiritually significant voices is proposed, which takes into account frequency, context, affect and identity of the voice. In a predominantly Christian sample of 58 people who reported having heard spiritually significant voices, most began in adult life and were infrequent experiences. Almost 90% reported that the voice was divine in identity and approximately one-third were heard in the context of prayer. The phenomenological characteristics of these voices were different from those in previous studies of voice hearing (AVHs). Most comprised a single voice; half were auditory; and a quarter were more thought-like (the rest being a mixture). Only half were characterful, and one-third included commands or prompts. The voices were experienced positively and as meaningful. The survey has implications for both clinical and pastoral work. The phenomenology of spiritually significant voices may be confused with that of psychopathology, thus potentially leading to misdiagnosis of normal religious experiences. The finding of meaning in content and context may be important in voice hearing more widely, and especially in coping with negative or distressing voices.

Cognitive and phenomenological characteristics of hallucination-proneness across the lifespan.

INTRODUCTION: The impact of age on hallucination-proneness within healthy adult cohorts and its relation to underlying cognitive mechanisms is underexplored. Based on previously researched trends in relation to cognitive ageing, we hypothesised that older and younger adults, when compared to a middle adult age group, would show differential relations between hallucination-proneness and cognitive performance. METHODS: A mixed methods, between-groups study was conducted with 30 young adults, 26 older adults, and 27 from a "middle adulthood" group. Participants completed a source memory task, jumbled speech task, Launay-Slade hallucination scale, unusual experiences schedule, and control measures of delusion-proneness and attitudes to mental health. RESULTS: Compared to older age-groups, younger participants demonstrated better scores on the source memory task, and reported hearing more words in jumbled speech. Additionally, younger cohorts rated higher on hallucination-proneness and disclosed more unusual experiences on a customised schedule designed to gather further qualitative data. Jumbled speech scores positively correlated with hallucination-proneness scores, particularly for the "middle" age group. Source memory performance unexpectedly correlated positively with hallucination-proneness, although this may be the product of age differences in task performance. CONCLUSIONS: Age differences in hallucination-proneness are evident on self-report and cognitive measures. Implications are discussed for potentially non-overlapping cognitive mechanisms underlying hallucination-proneness in non-clinical groups.

Tailoring cognitive behavioural therapy to subtypes of voice-hearing using a novel tabletised manual: a feasibility study.

BACKGROUND: Cognitive behavioural therapy for psychosis (CBTp) is a recommended treatment for psychotic experiences, but its effectiveness has been questioned. One way of addressing this may be to tailor therapy materials to the phenomenology of specific psychotic experiences. AIM: In this study, we investigated the acceptability of a novel treatment manual for subtypes of 'voice-hearing' experiences (i.e. auditory verbal hallucinations). An uncontrolled, single-arm design was used to assess feasibility and acceptability of using the manual in routine care for people with frequent voice-hearing experiences. METHOD: The manual was delivered on a smart tablet and incorporated recent research evidence and theory into its psychoeducation materials. In total, 24 participants completed a baseline assessment; 19 started treatment, 15 completed treatment and 12 participants completed a follow-up assessment (after 10 sessions of using the manual). RESULTS: Satisfaction with therapy scores and acceptability ratings were high, while completion rates suggested that the manual may be more appropriate for help with participants from Early Intervention in Psychosis services rather than Community Mental Health Teams. CONCLUSION: Within-group changes in symptom scores suggested that overall symptom severity of hallucinations - but not other psychosis features, or beliefs about voices - are likely to be the most appropriate primary outcome for further evaluation in a full randomised controlled trial.

Processing Speech and Thoughts during Silent Reading: Direct Reference Effects for Speech by Fictional Characters in Voice-Selective Auditory Cortex and a Theory-of-Mind Network.

Stories transport readers into vivid imaginative worlds, but understanding how readers create such worlds-populating them with characters, objects, and events-presents serious challenges across disciplines. Auditory imagery is thought to play a prominent role in this process, especially when representing characters' voices. Previous research has shown that direct reference to speech in stories (e.g., He said, "I'm over here") may prompt spontaneous activation of voice-selective auditory cortex more than indirect speech [Yao, B., Belin, P., & Scheepers, C. Silent reading of direct versus indirect speech activates voice-selective areas in the auditory cortex. Journal of Cognitive Neuroscience, 23, 3146-3152, 2011]. However, it is unclear whether this effect reflects differential processing of speech or differences in linguistic content, source memory, or grammar. One way to test this is to compare direct reference effects for characters speaking and thinking in a story. Here, we present a multidisciplinary fMRI study of 21 readers' responses to characters' speech and thoughts during silent reading of short fictional stories. Activations relating to direct and indirect references were compared for both speaking and thinking. Eye-tracking and independent localizer tasks (auditory cortex and theory of mind [ToM]) established ROIs in which responses to stories could be tracked for individuals. Evidence of elevated auditory cortex responses to direct speech over indirect speech was observed, replicating previously reported effects; no reference effect was observed for thoughts. Moreover, a direct reference effect specific to speech was also evident in regions previously associated with inferring intentions from communication. Implications are discussed for the spontaneous representation of fictional characters and the potential roles of inner speech and ToM in this process.

'I've learned I need to treat my characters like people': Varieties of agency and interaction in Writers' experiences of their Characters' Voices.

Writers often report vivid experiences of hearing characters talking to them, talking back to them, and exhibiting independence and autonomy. However, systematic empirical studies of this phenomenon are almost non-existent, and as a result little is known about its cause, extent, or phenomenology. Here we present the results of a survey of professional writers (n = 181) run in collaboration with the Edinburgh International Book Festival. Participants provided detailed descriptions of their experiences of their characters in response to a phenomenological questionnaire, and also reported on imaginary companions, inner speech and hallucination-proneness. Qualitative analysis indicated that the phenomenology of the experience of agentive characters varied in terms of the characters' separateness from the writer's self and the kinds of interaction this did or did not allow for. We argue that these variations can be understood in relation to accounts of mindreading and agency tracking which adopt intuitive as opposed to inferential models.

A linguistic approach to the psychosis continuum: (dis)similarities and (dis)continuities in how clinical and non-clinical voice-hearers talk about their voices.

Introduction: "Continuum" approaches to psychosis have generated reports of similarities and differences in voice-hearing in clinical and non-clinical populations at the cohort level, but not typically examined overlap or degrees of difference between groups. Methods: We used a computer-aided linguistic approach to explore reports of voice-hearing by a clinical group (Early Intervention in Psychosis service-users; N = 40) and a non-clinical group (spiritualists; N = 27). We identify semantic categories of terms statistically overused by one group compared with the other, and by each group compared to a control sample of non-voice-hearing interview data (log likelihood (LL) value 6.63+=p < .01; effect size measure: log ratio 1.0+). We consider whether individual values support a continuum model. Results: Notwithstanding significant cohort-level differences, there was considerable continuity in language use. Reports of negative affect were prominent in both groups (p < .01, log ratio: 1.12+). Challenges of cognitive control were also evident in both cohorts, with references to "disengagement" accentuated in service-users (p < .01, log ratio: 1.14+). Conclusion: A corpus linguistic approach to voice-hearing provides new evidence of differences between clinical and non-clinical groups. Variability at the individual level provides substantial evidence of continuity with implications for cognitive mechanisms underlying voice-hearing.

Distinct processing of ambiguous speech in people with non-clinical auditory verbal hallucinations.

Auditory verbal hallucinations (hearing voices) are typically associated with psychosis, but a minority of the general population also experience them frequently and without distress. Such 'non-clinical' experiences offer a rare and unique opportunity to study hallucinations apart from confounding clinical factors, thus allowing for the identification of symptom-specific mechanisms. Recent theories propose that hallucinations result from an imbalance of prior expectation and sensory information, but whether such an imbalance also influences auditory-perceptual processes remains unknown. We examine for the first time the cortical processing of ambiguous speech in people without psychosis who regularly hear voices. Twelve non-clinical voice-hearers and 17 matched controls completed a functional magnetic resonance imaging scan while passively listening to degraded speech ('sine-wave' speech), that was either potentially intelligible or unintelligible. Voice-hearers reported recognizing the presence of speech in the stimuli before controls, and before being explicitly informed of its intelligibility. Across both groups, intelligible sine-wave speech engaged a typical left-lateralized speech processing network. Notably, however, voice-hearers showed stronger intelligibility responses than controls in the dorsal anterior cingulate cortex and in the superior frontal gyrus. This suggests an enhanced involvement of attention and sensorimotor processes, selectively when speech was potentially intelligible. Altogether, these behavioural and neural findings indicate that people with hallucinatory experiences show distinct responses to meaningful auditory stimuli. A greater weighting towards prior knowledge and expectation might cause non-veridical auditory sensations in these individuals, but it might also spontaneously facilitate perceptual processing where such knowledge is required. This has implications for the understanding of hallucinations in clinical and non-clinical populations, and is consistent with current 'predictive processing' theories of psychosis.

Musical hallucinations, musical imagery, and earworms: A new phenomenological survey.

Musical hallucinations (MH) account for a significant proportion of auditory hallucinations, but there is a relative lack of research into their phenomenology. In contrast, much research has focused on other forms of internally generated musical experience, such as earworms (involuntary and repetitive inner music), showing that they can vary in perceived control, repetitiveness, and in their effect on mood. We conducted a large online survey (N = 270), including 44 participants with MH, asking participants to rate imagery, earworms, or MH on several variables. MH were reported as occurring less frequently, with less controllability, less lyrical content, and lower familiarity, than other forms of inner music. MH were also less likely to be reported by participants with higher levels of musical expertise. The findings are outlined in relation to other forms of hallucinatory experience and inner music, and their implications for psychological models of hallucinations discussed.

The varieties of inner speech questionnaire - Revised (VISQ-R): Replicating and refining links between inner speech and psychopathology.

Inner speech is a common experience for many but hard to measure empirically. The Varieties of Inner Speech Questionnaire (VISQ) has been used to link everyday phenomenology of inner speech - such as inner dialogue - to various psychopathological traits. However, positive and supportive aspects of inner speech have not always been captured. This study presents a revised version of the scale - the VISQ-R - based on factor analyses in two large samples: respondents to a survey on inner speech and reading (N = 1412) and a sample of university students (N = 377). Exploratory factor analysis indicated a five-factor structure including three previous subscales (dialogic, condensed, and other people in inner speech), an evaluative/critical factor, and a new positive/regulatory factor. Confirmatory factor analysis then replicated this structure in sample 2. Hierarchical regression analyses also replicated a number of relations between inner speech, hallucination-proneness, anxiety, depression, self-esteem, and dissociation.

Uncharted features and dynamics of reading: Voices, characters, and crossing of experiences.

Readers often describe vivid experiences of voices and characters in a manner that has been likened to hallucination. Little is known, however, of how common such experiences are, nor the individual differences they may reflect. Here we present the results of a 2014 survey conducted in collaboration with a national UK newspaper and an international book festival. Participants (n=1566) completed measures of reading imagery, inner speech, and hallucination-proneness, including 413 participants who provided detailed free-text descriptions of their reading experiences. Hierarchical regression analysis indicated that reading imagery was related to phenomenological characteristics of inner speech and proneness to hallucination-like experiences. However, qualitative analysis of reader's accounts suggested that vivid reading experiences were marked not just by auditory phenomenology, but also their tendency to cross over into non-reading contexts. This supports social-cognitive accounts of reading while highlighting a role for involuntary and uncontrolled personality models in the experience of fictional characters.

Auditory verbal hallucinations: Social, but how?

Auditory verbal hallucinations (AVH) are experiences of hearing voices in the absence of an external speaker. Standard explanatory models propose that AVH arise from misattributed verbal cognitions (i.e. inner speech), but provide little account of how heard voices often have a distinct persona and agency. Here we review the argument that AVH have important social and agent-like properties and consider how different neurocognitive approaches to AVH can account for these elements, focusing on inner speech, memory, and predictive processing. We then evaluate the possible role of separate social-cognitive processes in the development of AVH, before outlining three ways in which speech and language processes already involve socially important information, such as cues to interact with others. We propose that when these are taken into account, the social characteristics of AVH can be explained without an appeal to separate social-cognitive systems.

Shot through with voices: dissociation mediates the relationship between varieties of inner speech and auditory hallucination proneness.

Inner speech is a commonly experienced but poorly understood phenomenon. The Varieties of Inner Speech Questionnaire (VISQ; McCarthy-Jones & Fernyhough, 2011) assesses four characteristics of inner speech: dialogicality, evaluative/motivational content, condensation, and the presence of other people. Prior findings have linked anxiety and proneness to auditory hallucinations (AH) to these types of inner speech. This study extends that work by examining how inner speech relates to self-esteem and dissociation, and their combined impact upon AH-proneness. 156 students completed the VISQ and measures of self-esteem, dissociation and AH-proneness. Correlational analyses indicated that evaluative inner speech and other people in inner speech were associated with lower self-esteem and greater frequency of dissociative experiences. Dissociation and VISQ scores, but not self-esteem, predicted AH-proneness. Structural equation modelling supported a mediating role for dissociation between specific components of inner speech (evaluative and other people) and AH-proneness. Implications for the development of "hearing voices" are discussed.

Addressing the elephant in the screening room: an item response theory analysis of the Prodromal Questionnaire (PQ-16) for at-risk symptoms of psychosis.

OBJECTIVE: Within the context of patients at-risk of psychosis, where a variety of symptoms are present, identifying the most discriminative symptoms is essential for efficient detection and management. METHODS: This cross-sectional online study analyzed individuals from the general population in order to better assess their risk of presenting symptoms belonging to the clinical high risk (CHR) for psychosis, called "CHR-related symptoms". The Prodromal Questionnaire-16 (PQ-16) served as a self-report screening tool. Item response theory (IRT) with a graded response model was used to assess the discrimination and difficulty of its criteria. RESULTS: The analysis included 936 participants (mean age: 21.5 years; 28.1% male, 71.9% female). "Déjà vu" stood out for its high discriminative power, while "Voices or whispers" and "Seen things" demonstrated strong precision relatively to the other CHR-related symptoms. Conversely, "Smell or taste" and "Changing face" were associated with the most severe cases relatively to the other CHR-related symptoms. CONCLUSION: This study identified the most indicative CHR-related symptoms to emphasize their significance in accurately assessing severity and guiding targeted preventative interventions.

Effects of a novel, brief psychological therapy (Managing Unusual Sensory Experiences) for hallucinations in first episode psychosis (MUSE FEP): Findings from an exploratory randomised controlled trial.

Hallucinations are a common feature of psychosis, yet access to effective psychological treatment is limited. The Managing Unusual Sensory Experiences for First-Episode-Psychosis (MUSE-FEP) trial aimed to establish the feasibility and acceptability of a brief, hallucination-specific, digitally provided treatment, delivered by a non-specialist workforce for people with psychosis. MUSE uses psychoeducation about the causal mechanisms of hallucinations and tailored interventions to help a person understand and manage their experiences. We undertook a two-site, single-blind (rater) Randomised Controlled Trial and recruited 82 participants who were allocated 1:1 to MUSE and treatment as usual (TAU) (n = 40) or TAU alone (n = 42). Participants completed assessments before and after treatment (2 months), and at follow up (3-4 months). Information on recruitment rates, adherence, and completion of outcome assessments was collected. Analyses focussed on feasibility outcomes and initial estimates of intervention effects to inform a future trial. The trial is registered with the ISRCTN registry 16793301. Criteria for the feasibility of trial methodology and intervention delivery were met. The trial exceeded the recruitment target, had high retention rates (87.8%) at end of treatment, and at follow up (86.6%), with good acceptability of treatment. There were 3 serious adverse events in the therapy group, and 5 in the TAU group. Improvements were evident in both groups at the end of treatment and follow up, with a particular benefit in perceived recovery in the MUSE group. We showed it was feasible to increase access to psychological intervention but a definitive trial requires further changes to the trial design or treatment.