Occurrence and co-occurrence of hallucinations by modality in schizophrenia-spectrum disorders

Content-based clustering of hallucinations across sensory modalities in a large online survey

Hallucinations can have rather heterogeneous aetiology and presentation. This inspired the concept of different subtypes based on symptom profiles, especially in the field of auditory hallucinations. As many people experience hallucinations in more than one sensory modality, it seems important to investigate potential hallucination subtypes across different sensory modalities. We assessed the content of hallucinations as part of a large survey among the general Dutch population (n = 10,448) using the Questionnaire for Psychotic Experiences. Based on their descriptions, thematic categories were created in a data-driven cluster analysis. 2594 participants who experienced hallucinations over the past week that contained at least 2 different thematic categories were selected. Clustering of their hallucination content was performed with the HDBSCAN method. We identified 4 clusters, i.e., subtypes, which can be typified as 1. hallucinations of foul odors, 2. complex visual scenes, 3. a vast variety of rather common hallucinations possibly related to heightened alertness, and 4. possibly bereavement hallucinations. The bereavement subtype showed an increase in emotional loneliness and the presence of delusions. Our findings suggest that the content of hallucinations can be informative, especially when investigated across sensory modalities. Such subtypes may help to better understand their underlying mechanisms.

Creative puppet therapy reduces hallucinations in patients diagnosed with schizophrenia: Preliminary findings

Anomalous experiences and hallucinations characterize schizophrenia. This study aimed at determining the efficacy of creative puppet therapy (CPT; creation of a puppet with malleable DAS) to reduce severe anomalous experiences and hallucinations among patients diagnosed with schizophrenia. Double-blinded, controlled trials were performed on a convenience sample of 24 patients from a mental health center. The intervention group of 12 patients (who created puppets) and the pseudo-treatment group of 12 patients (who were involved in outdoor leisure trips) were compared to the control group of 12 control participants (who created puppets). Cardiff Anomalous Perceptions Scale (CAPS) assessed hallucinations; Emotional Expression Inventory (EEXI) assessed the emotional expression of one's own puppet. Puppet facial features were measured. Results showed that CPT effectively reduced (d = -4.00) hallucination frequency in patients. Hallucination reduction occurred across all sensory modalities, but touch and bodily interoception. Exteroceptive vs. interoceptive hallucinations was the most valuable classification in patients. Compared to controls, puppets created by patients expressed more negative emotions and had larger eye diameters, shorter noses, and larger whole face width. Eye diameter was correlated with fear, sadness, anger, and disgust, and whole face width with boredom. Fragmented-self integration of schizophrenia through CPT treatment might exploit aggregative dominance of the patient's own body.

Reducing Distress from Auditory Verbal Hallucinations: A Multicenter, Parallel, Single-Blind, Randomized Controlled Feasibility Trial of Relating Therapy

INTRODUCTION

There is a significant demand for interventions that reduce distress related to auditory verbal hallucinations (AVHs). AVH distress is associated with the way voice hearers relate with AVHs. We aimed to establish the feasibility of a randomized controlled trial to demonstrate that adding "Relating Therapy" (RT) to treatment as usual (TAU) is superior to TAU in reducing AVH distress.

METHODS

We conducted a multicenter, parallel, single-blind, randomized controlled feasibility trial in five mental health centers in Germany. Participants were ≥19 years of age, had persistent and distressing AVHs, and had a diagnosis of a schizophrenia-spectrum disorder. RT was delivered over a maximum of 16 sessions within 5 months. Blind assessments were conducted at baseline and at 5 and 9 months. Feasibility outcomes were the number of patients recruited and retained, and safety and therapist adherence. The primary endpoint was the distress factor score of the AVH subscale of the Psychotic Symptoms Rating Scales at 9 months.

RESULTS

Eighty-five of 177 enrolled participants were randomized into RT + TAU (n = 43) or TAU (n = 42). Feasibility was excellent with 87% retention at 9 months, 86% reaching treatment uptake criteria, 98% therapist adherence, and no unexpected serious adverse reactions. Compared to TAU, RT + TAU showed nonsignificant trends toward less AVH distress (b = -2.40, SE = 1.52, p = 0.121, 90% CI (-4.94 to 0.15) and stronger improvement on all but one of the secondary outcomes.

CONCLUSION

A randomized controlled trial of RT is feasible, safe, and well accepted. Our results provide an encouraging basis to further test the efficacy of RT in a definitive multicenter trial.

Spatial Dynamic Subspaces Encode Sex-Specific Schizophrenia Disruptions in Transient Network Overlap and Their Links to Genetic Risk

BACKGROUND

Schizophrenia research reveals sex differences in incidence, symptoms, genetic risk factors, and brain function. However, a knowledge gap remains regarding sex-specific schizophrenia alterations in brain function. Schizophrenia is considered a dysconnectivity syndrome, but the dynamic integration and segregation of brain networks are poorly understood. Recent advances in resting-state functional magnetic resonance imaging allow us to study spatial dynamics, the phenomenon of brain networks spatially evolving over time. Nevertheless, estimating time-resolved networks remains challenging due to low signal-to-noise ratio, limited short-time information, and uncertain network identification.

METHODS

We adapted a reference-informed network estimation technique to capture time-resolved networks and their dynamic spatial integration and segregation for 193 individuals with schizophrenia and 315 control participants. We focused on time-resolved spatial functional network connectivity, an estimate of network spatial coupling, to study sex-specific alterations in schizophrenia and their links to genomic data.

RESULTS

Our findings are consistent with the dysconnectivity and neurodevelopment hypotheses and with the cerebello-thalamo-cortical, triple-network, and frontoparietal dysconnectivity models, helping to unify them. The potential unification offers a new understanding of the underlying mechanisms. Notably, the posterior default mode/salience spatial functional network connectivity exhibits sex-specific schizophrenia alteration during the state with the highest global network integration and is correlated with genetic risk for schizophrenia. This dysfunction is reflected in regions with weak functional connectivity to corresponding networks.

CONCLUSIONS

Our method can effectively capture spatially dynamic networks, detect nuanced schizophrenia effects including sex-specific ones, and reveal the intricate relationship of dynamic information to genomic data. The results also underscore the clinical potential of dynamic spatial dependence and weak connectivity.

Targeted psychological and psychosocial interventions for auditory hallucinations in persons with psychotic disorders: Protocol for a systematic review and meta-analysis

BACKGROUND

In recent years, a growing body of evidence has demonstrated the efficacy of non-pharmacological interventions for schizophrenia spectrum disorders (SSD) including positive symptoms such as auditory hallucinations (AH). However, clinical trials predominantly examine general treatment effects for positive symptoms. Therefore, previous research is lacking in comprehensive and clear evidence about psychological and psychosocial approaches that are primarily tailored to treat AH. To overcome this knowledge gap in the current literature, we will conduct a systematic review and meta-analysis to assess the efficacy of clearly targeted psychological and psychosocial interventions for AH in persons with SSD.

METHODS AND ANALYSIS

This study protocol has been developed according to the guidelines of the Preferred Reporting Items for Systematic Reviews and Meta-Analysis Protocols. We will include all randomized controlled trials analyzing the efficacy of targeted psychological and psychosocial interventions especially aimed at treating AH in SSD. We will include studies on adult patients with SSD experiencing AH. The primary outcome will be the change on a published rating scale measuring AH. Secondary outcomes will be delusions, overall symptoms, negative symptoms, depression, social functioning, quality of life, and acceptability (drop-out). We will search relevant databases and the reference lists of included literature. The study selection process will be conducted by two independent reviewers. We will conduct a random-effect meta-analysis to consider heterogeneity across studies. Analyses will be carried out by software packages in R. The risk of bias in each study will be evaluated using the Cochrane Risk of Bias tool. Assessment of heterogeneity and sensitivity analysis will be conducted.

DISCUSSION

The proposed study will augment the existing evidence by providing an overview of effective treatment approaches and their overall efficacy at treating AH in SSD. These findings will complement existing evidence that may impact future treatment implementations in clinical practice by addressing effective strategies to treat AH and therefore improve outcomes for the addressed population.

ETHICS AND DISSEMINATION

No ethical issues are foreseen. We will publish the results from this study in peer-reviewed journals and at relevant scientific conferences.

TRIAL REGISTRATION

PROSPERO registration number: CRD42023475704.

Examining the relationships between cognition and auditory hallucinations: A systematic review

OBJECTIVE

Auditory hallucinations (hearing voices) have been associated with a range of altered cognitive functions, pertaining to signal detection, source-monitoring, memory, inhibition and language processes. Yet, empirical results are inconsistent. Despite this, several theoretical models of auditory hallucinations persist, alongside increasing emphasis on the utility of a multidimensional framework. Thus, clarification of current evidence across the broad scope of proposed mechanisms is warranted.

METHOD

A systematic search of the Web of Science, PubMed and Scopus databases was conducted. Records were screened to confirm the use of an objective behavioural cognitive task, and valid measurement of hallucinations specific to the auditory modality.

RESULTS

Auditory hallucinations were primarily associated with difficulties in perceptual decision-making (i.e. reduced sensitivity/accuracy for signal-noise discrimination; liberal responding to ambiguity), source-monitoring (i.e. self-other and temporal context confusion), working memory and language function (i.e. reduced verbal fluency). Mixed or limited support was observed for perceptual feature discrimination, imagery vividness/illusion susceptibility, source-monitoring for stimulus form and spatial context, recognition and recall memory, executive functions (e.g. attention, inhibition), emotion processing and language comprehension/hemispheric organisation.

CONCLUSIONS

Findings were considered within predictive coding and self-monitoring frameworks. Of concern was the portion of studies which - despite offering auditory-hallucination-specific aims and inferences - employed modality-general measures, and/or diagnostic-based contrasts with psychologically healthy individuals. This review highlights disparities within the literature between theoretical conceptualisations of auditory hallucinations and the body of rigorous empirical evidence supporting such inferences. Future cognitive investigations, beyond the schizophrenia-spectrum, which explicitly define and measure the timeframe and sensory modality of hallucinations, are recommended.

Does insecure attachment lead to psychosis via dissociation? A systematic review of the literature

PURPOSE

Insecure attachment may constitute a vulnerability factor for psychosis, and dissociation may be a key mechanism in the development of auditory hallucinations specifically. While there is good evidence for the role of these processes in isolation, it is unclear whether dissociation accounts for the association between insecure attachment and psychosis. This systematic review takes a theory-driven approach to examine proposed causal relationships across the clinical and nonclinical literature.

METHODS

We searched five databases (PubMeD, Web of Science, PsycINFO, CINAHL and ETHOS) for published and unpublished research examining attachment, dissociation and psychosis. Two independent reviewers extracted the data and assessed the quality of all included studies.

RESULTS

We identified 242 potential articles and included 13 in the final review (2096 participants). We found that (1) disorganised attachment was consistently associated with dissociation and inconsistently associated with voices and paranoia, (2) dissociation was associated with voices and paranoia, and these links were stronger in clinical samples, and (3) dissociation played a role in the impact of insecure attachment on voice hearing and paranoia in clinical groups.

CONCLUSIONS

This is the first review to synthesise the research examining attachment, dissociation, and psychosis. The evidence is consistent with proposed causal hypotheses and raises conceptual and measurement issues, for example, the need to clarify the relative contributions of different insecure attachment styles, and utilise behavioural/observational measures to strengthen study designs. Most importantly, we need experimental and longitudinal studies to confirm causal links and targets for treatment.

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.

The Phenomenology of Visual and Other Nonauditory Hallucinations in Affective and Nonaffective Psychosis: A Mixed Methods Analysis

ABSTRACT

Nonauditory hallucinations in psychosis have not received as much attention relative to voice-hearing experiences. The current paper aimed to document the characteristics of these hallucinations in affective and nonaffective psychosis. Participants were selected from a primary voice-hearing sample, who had endorsed visual, tactile, or olfactory hallucinations ( N = 55-75). A comprehensive, semistructured phenomenological interview was conducted, followed by mixed methods analysis. Visual hallucinations typically occurred daily, for a few minutes per episode, within one's direct line of sight; persons and/or animals were most commonly seen, with low controllability and mostly engendered negative affective outcomes. Tactile and olfactory hallucinations were endorsed by 46.8% and 39.0% of participants, respectively. The affective psychosis group ( n = 33) reported significantly greater awareness and lower functional impairment relative to the nonaffective psychosis group ( n = 42). Qualitative thematic analysis revealed notable themes and subthemes across each of these hallucinations modes. Further phenomenological investigations should be carried out in lesser known hallucination modalities, assisted by the development of appropriate assessment tools.

The relationship between visual hallucinations, functioning, and suicidality over the course of illness: a 10-year follow-up study in first-episode psychosis

Visual hallucinations in psychosis are under-researched despite associations with increased illness severity, functional impairments, and suicidality in the few existing studies. Further, there are no long-term longitudinal studies, making it impossible to conclude if these associations are state or trait phenomena. In the current prospective longitudinal study, 184 individuals with first-episode psychosis were assessed with semi-structured clinical interviews and self-report questionnaires at baseline and 10-year follow-up. Participants were grouped based on lifetime experience of visual hallucinations: before or at baseline (VH+/+), first during follow-up (VH-/+), or never (VH-/-). Associations with functioning, suicide attempts, childhood trauma and other markers of illness severity were tested using multinomial logistic regression analysis. At baseline, the VH+/+ group (37.5%), but not VH-/+ (12.5%), had poorer functioning, higher symptom severity, a lower age at onset, and included more individuals with a history of multiple suicide attempts than the VH-/- group (50%). At follow-up, the VH-/+ group, but not VH+/+, had poorer functioning and higher symptom severity than the VH-/- group. However, the number of participants who committed multiple suicide attempts during the follow-up period was again significantly higher in the VH+/+ group. There was no association with childhood trauma. Hence, visual hallucinations are associated with impaired functioning and higher symptom severity, but only in the short-term. However, visual hallucinations that arise early in the course of illness are a risk indicator for repeated suicide attempts throughout the illness course. These findings highlight the relevance of assessing visual hallucinations and monitoring their development over time.

White matter tracts differentially associated with auditory hallucinations in first-episode psychosis: A correlational tractography diffusion spectrum imaging study

Auditory hallucinations (AH) are a debilitating symptom in psychosis, impacting cognition and real world functioning. Recent thought conceptualizes AH as a consequence of long-range brain communication dysfunction, or circuitopathy, within the auditory sensory/perceptual, language, and cognitive control systems. Recently we showed in first-episode psychosis (FEP) that, despite overall intact white matter integrity in the cortical-cortical and cortical-subcortical language tracts and the callosal tracts connecting auditory cortices, the severity of AH correlated inversely with white matter integrity. However, that hypothesis-driven isolation of specific tracts likely missed important white matter concomitants of AH. In this report, we used a whole-brain data-driven dimensional approach using correlational tractography to associate AH severity with white matter integrity in a sample of 175 individuals. Diffusion Spectrum Imaging (DSI) was used to image diffusion distribution. Quantitative Anisotropy (QA) in three tracts was greater with increased AH severity (FDR < 0.001) and QA in three tracts was lower with increased AH severity (FDR < 0.01). White matter tracts showing associations between QA and AH were generally associated with frontal-parietal-temporal connectivity (tracts with known relevance for cognitive control and the language system), in the cingulum bundle, and in prefrontal inter-hemispheric connectivity. The results of this whole brain data-driven analysis suggest that subtle white matter alterations connecting frontal, parietal, and temporal lobes in the service of sensory-perceptual, language/semantic, and cognitive control processes impact the expression of auditory hallucination in FEP. Disentangling the distributed neural circuits involved in AH should help to develop novel interventions, such as non-invasive brain stimulation.

Non-clinical hallucinations and mental imagery across sensory modalities

INTRODUCTION

Vivid mental imagery has been proposed to increase the likelihood of experiencing hallucinations. Typically, studies have employed a modality general approach to mental imagery which compares imagery across multiple domains (e.g., visual, auditory and tactile) to hallucinations in multiple senses. However, modality specific imagery may be a better predictor of hallucinations in the same domain. The study examined the contribution of imagery to hallucinations in a non-clinical sample and specifically whether imagery best predicted hallucinations at a modality general or modality specific level.

METHODS

In study one, modality general and modality specific accounts of the imagery-hallucination relationship were contrasted through application of self-report measures in a sample of 434 students. Study two used a subsample (n = 103) to extend exploration of the imagery-hallucinations relationship using a performance-based imagery task.

RESULTS

A small to moderate modality general relationship was observed between self-report imagery and hallucination proneness. There was only evidence of a modality specific relationship in the tactile domain. Performance-based imagery measures were unrelated to hallucinations and self-report imagery.

CONCLUSIONS

Mental imagery may act as a modality general process increasing hallucination proneness. The observed distinction between self-report and performance-based imagery highlights the difficulty of accurately measuring internal processes.

Hallucination-Proneness is Associated With a Decrease in Robust Averaging of Perceptual Evidence

BACKGROUND AND HYPOTHESIS

Hallucinations are characterized by disturbances in perceptual decision-making about environmental stimuli. When integrating across multiple stimuli to form a perceptual decision, typical observers engage in "robust averaging" by down-weighting extreme perceptual evidence, akin to a statistician excluding outlying data. Furthermore, observers adapt to contexts with more unreliable evidence by increasing this down-weighting strategy. Here, we test the hypothesis that hallucination-prone individuals (n = 38 high vs n = 91 low) would show a decrease in this robust averaging and diminished sensitivity to changes in evidence variance.

STUDY DESIGN

We used a multielement perceptual averaging task to elicit dichotomous judgments about the "average color" (red/blue) of an array of stimuli in trials with varied strength (mean) and reliability (variance) of decision-relevant perceptual evidence. We fitted computational models to task behavior, with a focus on a log-posterior-ratio (LPR) model which integrates evidence as a function of the log odds of each perceptual option and produces a robust averaging effect.

STUDY RESULTS

Hallucination-prone individuals demonstrated less robust averaging, seeming to weigh inlying and outlying extreme or untrustworthy evidence more equally. Furthermore, the model that integrated evidence as a function of the LPR of the two perceptual options and produced robust averaging showed poorer fit for the group prone to hallucinations. Finally, the weighting strategy in hallucination-prone individuals remained insensitive to evidence variance.

CONCLUSIONS

Our findings provide empirical support for theoretical proposals regarding evidence integration aberrations in psychosis and alterations in the perceptual systems that track statistical regularities in environmental stimuli.

Exploring the cognitive profiles related to unimodal auditory versus multisensory hallucinations in schizophrenia-spectrum disorders

INTRODUCTION

Hallucinations can be experienced across multiple sensory modalities, but psychiatric studies investigating the cognitive mechanisms of hallucinations have been somewhat restricted to the auditory domain. This study explored the cognitive profiles of individuals experiencing multisensory hallucinations (MH) in schizophrenia-spectrum disorders (SSD) and compared these to those experiencing unimodal auditory hallucinations (AH) or no hallucinations (NH).

METHODS

Participants included SSD patients (n = 119) stratified by current hallucination status (NH, AH, MH) and nonclinical controls (NCs; n = 113). Group performance was compared across several cognitive domains: speed of processing, attention, working memory, verbal learning, visual learning, reasoning and problem-solving, social cognition, and inhibition.

RESULTS

The clinical groups performed worse than NCs but differences between the clinical groups were not evident across most cognitive domains. Exploratory analyses revealed that the MH group was more impaired on the visual learning task compared to the NH (but not AH) group.

CONCLUSIONS

Preliminary results suggest that impaired visual learning may be related to MH. This could be attributed to the presence of visual hallucinations (VH), or greater psychopathology, in this group. However, replication is needed, as well as the investigation of other potential cognitive mechanisms of MH.

A comprehensive update on genetic inheritance, epigenetic factors, associated pathology, and recent therapeutic intervention by gene therapy in schizophrenia

Schizophrenia is a severe psychological disorder in which reality is interpreted abnormally by the patient. The symptoms of the disease include delusions and hallucinations, associated with extremely disordered behavior and thinking, which may affect the daily lives of the patients. Advancements in technology have led to understanding the dynamics of the disease and the identification of the underlying causes. Multiple investigations prove that it is regulated genetically, and epigenetically, and is affected by environmental factors. The molecular and neural pathways linked to the regulation of schizophrenia have been extensively studied. Over 180 Schizophrenic risk loci have now been recognized due to several genome-wide association studies (GWAS). It has been observed that multiple transcription factors (TF) binding-disrupting single nucleotide polymorphisms (SNPs) have been related to gene expression responsible for the disease in cerebral complexes. Copy number variation, SNP defects, and epigenetic changes in chromosomes may cause overexpression or underexpression of certain genes responsible for the disease. Nowadays, gene therapy is being implemented for its treatment as several of these genetic defects have been identified. Scientists are trying to use viral vectors, miRNA, siRNA, and CRISPR technology. In addition, nanotechnology is also being applied to target such genes. The primary aim of such targeting was to either delete or silence such hyperactive genes or induce certain genes that inhibit the expression of these genes. There are challenges in delivering the gene/DNA to the site of action in the brain, and scientists are working to resolve the same. The present article describes the basics regarding the disease, its causes and factors responsible, and the gene therapy solutions available to treat this disease.

Negative Impacts of Psychiatric Medications on Oral Health: A Literature Review

Evidence reveals that people with mental illnesses have a greater risk of experiencing oral diseases such as dry mouth and dental caries and have greater oral treatment needs. This is related to multifactorial causes such as factors related to the condition itself, symptoms, side effects of polypharmacy, and a lack of accessibility to dental services. This article aims to provide a summary of the reported prevalence of the most common mental illnesses in Saudi Arabia (SA), such as schizophrenia, obsessive-compulsive disorder (OCD), bipolar disorders, and dementia. The article further aims to review the negative impacts of anti-psychotic medications on oral health and the role of dentists toward people with mental illnesses. PubMed, Scopus, and Google Scholar were searched using the following keywords: special care dentistry, schizophrenia, OCD, bipolar disorder, and dementia. The main inclusion criteria were any studies describing "dental management of patients with mental illnesses" and "dental management of patients treated with anti-psychotic medications." Thematic analysis was used to summarize the findings of the included studies into main headings. Forty-eight articles/studies discussed dentistry, people with mental illnesses, and/or the negative impacts of psychotic medication on oral health. All studies were published between 1991 and 2021. In SA, the number of people with mental illnesses is increasing. Therefore, it is crucial for the dental team to understand the negative impacts of anti-psychotic medications on oral health, such as dry mouth and the increased risk of dental caries. This necessitates the need for regular dental visits and patient education on how they can mitigate the side effects of anti-psychotic medications on oral and general health.

A pilot study to investigate the efficacy and tolerability of lesion network guided transcranial electrical stimulation in outpatients with psychosis spectrum illness

BACKGROUND

Transcranial electrical stimulation (tES) may improve psychosis symptoms, but few investigations have targeted brain regions causally linked to psychosis symptoms. We implemented a novel montage targeting the extrastriate visual cortex (eVC) previously identified by lesion network mapping in the manifestation of visual hallucinations.

OBJECTIVE

To determine if lesion network guided High Definition-tES (HD-tES) to the eVC is safe and efficacious in reducing symptoms related to psychosis.

METHODS

We conducted a single-blind crossover pilot study (NCT04870710) in patients with psychosis spectrum disorders. Participants first received HD-tDCS (direct current), followed by 4 weeks of wash out, then 2 Hz HD-tACS (alternating current). Participants received 5 days of daily (2×20 min) stimulation bilaterally to the eVC. Primary outcomes included the Positive and Negative Syndrome Scale (PANSS), biological motion task, and Event Related Potentials (ERP) from a steady state visual evoked potential (SSVEP) paradigm. Secondary outcomes included the Montgomery-Asperg Depression Rating Scale, Global Assessment of Functioning (GAF), velocity discrimination and visual working memory task, and emotional ERP.

RESULTS

HD-tDCS improved PANSS general psychopathology in the short-term (d=0.47; pfdr=0.03), with long-term improvements in general psychopathology (d=0.62; pfdr=0.05) and GAF (d=-0.56; pfdr=0.04) with HD-tACS. HD-tDCS reduced SSVEP P1 (d=0.25; pfdr=0.005), which correlated with general psychopathology (β = 0.274, t = 3.59, p = 0.04). No significant differences in safety or tolerability measures were identified.

CONCLUSION

Lesion network guided HD-tES to the eVC is a safe, efficacious, and promising approach for reducing general psychopathology via changes in neuroplasticity. These results highlight the need for larger clinical trials implementing novel targeting methodologies for the treatments of psychosis.

Mismatch negativity and clinical trajectories in psychotic disorders: Five-year stability and predictive utility

BACKGROUND

Mismatch negativity (MMN) amplitude is reduced in psychotic disorders and associated with symptoms and functioning. Due to these robust associations, it is often considered a biomarker for psychotic illness. The relationship between MMN and clinical outcomes has been examined well in early onset psychotic illness; however, its stability and predictive utility in chronic samples are not clear.

METHOD

We examined the five-year stability of MMN amplitude over two timepoints in individuals with established psychotic disorders (cases; N = 132) and never-psychotic participants (NP; N = 170), as well as longitudinal associations with clinical symptoms and functioning.

RESULTS

MMN amplitude exhibited good temporal stability (cases, r = 0.53; never-psychotic, r = 0.52). In cases, structural equation models revealed MMN amplitude to be a significant predictor of worsening auditory hallucinations (β = 0.19), everyday functioning (β = -0.13), and illness severity (β = -0.12) at follow-up. Meanwhile, initial IQ (β = -0.24), negative symptoms (β = 0.23), and illness severity (β = -0.16) were significant predictors of worsening MMN amplitude five years later.

CONCLUSIONS

These results imply that MMN measures a neural deficit that is reasonably stable up to five years. Results support disordered cognition and negative symptoms as preceding reduced MMN, which then may operate as a mechanism driving reductions in everyday functioning and the worsening of auditory hallucinations in chronic psychotic disorders. This pattern may inform models of illness course, clarifying the relationships amongst biological mechanisms of predictive processing and clinical deficits in chronic psychosis and allowing us to better understand the mechanisms driving such impairments over time.

Spatial Dynamic Subspaces Encode Sex-Specific Schizophrenia Disruptions in Transient Network Overlap and its Links to Genetic Risk

Background

Recent advances in resting-state fMRI allow us to study spatial dynamics, the phenomenon of brain networks spatially evolving over time. However, most dynamic studies still use subject-specific, spatially-static nodes. As recent studies have demonstrated, incorporating time-resolved spatial properties is crucial for precise functional connectivity estimation and gaining unique insights into brain function. Nevertheless, estimating time-resolved networks poses challenges due to the low signal-to-noise ratio, limited information in short time segments, and uncertain identification of corresponding networks within and between subjects.

Methods

We adapt a reference-informed network estimation technique to capture time-resolved spatial networks and their dynamic spatial integration and segregation. We focus on time-resolved spatial functional network connectivity (spFNC), an estimate of network spatial coupling, to study sex-specific alterations in schizophrenia and their links to multi-factorial genomic data.

Results

Our findings are consistent with the dysconnectivity and neurodevelopment hypotheses and align with the cerebello-thalamo-cortical, triple-network, and frontoparietal dysconnectivity models, helping to unify them. The potential unification offers a new understanding of the underlying mechanisms. Notably, the posterior default mode/salience spFNC exhibits sex-specific schizophrenia alteration during the state with the highest global network integration and correlates with genetic risk for schizophrenia. This dysfunction is also reflected in high-dimensional (voxel-level) space in regions with weak functional connectivity to corresponding networks.

Conclusions

Our method can effectively capture spatially dynamic networks, detect nuanced SZ effects, and reveal the intricate relationship of dynamic information to genomic data. The results also underscore the potential of dynamic spatial dependence and weak connectivity in the clinical landscape.

Exploring the associations between auditory hallucinations and psychopathological experiences in 10,933 patient narratives: moving beyond diagnostic categories and surveys

BACKGROUND

Previous research suggests that auditory hallucinations are prevalent within both the clinical and general populations. Yet, we know little about how these phenomena are associated with other psychopathology symptoms and experiences. The current study aids investigations towards preventing, predicting and more effectively responding to such distressing occurrences. There have been substantial efforts in the literature to propose models of auditory hallucination and attempts to verify them. However, many of these studies used survey methods that restrict the person's responses to a set of pre-defined criteria or experiences and do not allow exploration of potential important other symptoms beyond them. This is the first study to explore the correlates of auditory hallucination using a qualitative dataset consisting of unrestricted responses of patients about their lived experiences with mental illness.

METHOD

The study used a dataset consisting of 10,933 narratives from patients diagnosed with mental illnesses. For analysis, the study used correlation on the text-based data. This approach is an alternative to the knowledge-based approach where experts manually read the narratives and infer the rules and relationships from the dataset.

RESULT

This study found at least 8 correlates of auditory hallucination (small correlation coefficients), with the unusual ones being "pain." The study also found that auditory hallucinations were independent of obsessive thoughts and compulsive behaviours, and dissociation, in contrast with the literature.

CONCLUSION

This study presents an innovative approach to explore the possible associations between symptoms without the restrictions of (or outside the confines of) traditional diagnostic categories. The study exemplified this by finding the correlates of auditory hallucination. However, any other symptom or experience of interest can be studied similarly. Potential future directions of these findings are discussed in the context of mental healthcare screening and treatment.

Prevalence of multisensory hallucinations in people at risk of transition to psychosis

Hallucinations can occur in single or multiple sensory modalities. Greater attention has been paid to single sensory experiences with a comparative neglect of hallucinations that occur across two or more sensory modalities (multisensory hallucinations). This study explored how common these experiences were in people at risk of transition to psychosis (n=105) and considered whether a greater number of hallucinatory experiences increased delusional ideation and reduced functioning, both of which are associated with a greater risk of transition to psychosis. Participants reported a range of unusual sensory experiences, with two or three being common. However, when a strict definition of hallucinations was applied, in which the experience has the quality of a real perception and in which the person believes them to be real experiences, then multisensory experiences were rare and when reported, single sensory hallucinations in the auditory domain were most common. The number of unusual sensory experiences or hallucinations was not significantly associated with greater delusional ideation or poorer functioning. Theoretical and clinical implications are discussed.

Association between visual impairment and psychosis: A longitudinal study and nested case-control study of adults

BACKGROUND

Theories propose that visual impairment might increase the risk of psychosis, and vice versa. We aimed to investigate the relationship between visual impairment and psychosis in the UK Biobank cohort.

STUDY DESIGN

In a nested case control study of ~116,000 adults, we tested whether a Schizophrenia Spectrum Disorder (SSD) diagnosis as exposure was associated with visual impairment. We also tested longitudinally whether poorer visual acuity, and thinner retinal structures on Optical Coherence Tomography (OCT) scans in 2009 were associated with psychotic experiences in 2016. We adjusted for age, sex, depression and anxiety symptoms; and socioeconomic variables and vascular risk factors where appropriate. We compared complete case with multiple imputation models, designed to reduce bias potentially introduced by missing data.

RESULTS

People with visual impairment had greater odds of SSD than controls in multiply imputed data (Adjusted Odds Ratio [AOR] 1.42, 95 % Confidence Interval [CI] 1.05-1.93, p = 0.021). We also found evidence that poorer visual acuity was associated with psychotic experiences during follow-up (AOR per 0.1 point worse visual acuity score 1.06, 95 % CI 1.01-1.11, p = 0.020; and 1.04, 95 % CI 1.00-1.08, p = 0.037 in right and left eye respectively). In complete case data (15 % of this cohort) we found no clear association, although confidence intervals included the multiple imputation effect estimates. OCT measures were not associated with psychotic experiences.

CONCLUSIONS

Our findings highlight the importance of eye care for people with psychotic illnesses. We could not conclude whether visual impairment is a likely causal risk factor for psychosis.

Prevalence and nature of multi-sensory and multi-modal hallucinations in people with first episode psychosis

Hallucinations can occur in single or multiple sensory modalities. This study explored how common these experiences were in people with first episode of psychosis (n = 82). Particular attention was paid to the number of modalities reported and whether the experiences were seen to be linked temporally and thematically. It was predicted that those people reporting a greater number of hallucinations would report more delusional ideation, greater levels of distress generally and lower functioning. All participants reported hallucinations in the auditory domain, given the nature of the recruitment. The participants also reported a range of other unusual sensory experiences, with visual and tactile hallucinations being reported by over half. Moreover, single sensory experiences or unimodal hallucinations were less common than two or more hallucination modalities which was reported by 78% of the participants. The number of hallucinations was significantly associated with greater delusional ideation and higher levels of general distress, but not with reduced functioning. It is clear there is a need to refine psychological treatments so that they are better matched to the actual experiences reported by people with psychosis. Theoretical implications are also considered.

Factor structure and item response of psychosis symptoms among Kenyan adults

BACKGROUND

The aim of this study was to evaluate the construct validity of the psychosis module of the Mini International Neuropsychiatric Interview version 7.0.2 (MINI-7).

METHOD

We utilized data collected from 2738 participants with a primary psychotic or bipolar disorder. Participants were drawn from two Kenyan sites of a large multi-center neuropsychiatric genetic study. The factor structure of the MINI-7 psychosis items were explored using confirmatory factor analyses (CFA) and Item Response Theory approach, for the full sample and by gender.

RESULTS

The CFA revealed that a 1-factor model provided adequate fit for the MINI-7 psychosis items for the full sample (x2 = 397.92, df = 35, p < .0001; RMSEA = 0.06; CFI = 0.92; TLI = 0.90) as well as for the female (x2 = 185.16.92, df = 35, p < .0001; RMSEA = 0.06; CFI = 0.93; TLI = 0.91) and male groups (x2 = 242.09, df = 35, p < .0001; RMSEA = 0.06; CFI = 0.92; TLI = 0.89). Item thresholds for the full sample, and female and male groups were highest for 'odd beliefs' (-1.42, -1.33, and -1.51 respectively) and lowest for 'visual hallucinations' (-0.03, -0.04, and -0.01 respectively).

LIMITATIONS

Our study used a hospital-based population, which may have excluded patients with milder psychotic symptoms. Findings may therefore not be generalizable to the community setting.

CONCLUSIONS

Our findings indicate good construct validity of the MINI-7 psychosis module, and provides support for use of the tool in diagnosing psychotic disorders in clinical settings in Kenya.

Pathological resting-state executive and language system perfusion in first-episode psychosis

BACKGROUND AND HYPOTHESIS

Cortical (e.g., Broca's area and Wernicke's area) and subcortical (e.g., putamen) language-related areas and executive control areas (e.g., inferior frontal gyrus (IFG), dorsolateral prefrontal cortex (DLPFC)) show functional and structural dysconnectivity in long-term psychosis. We examined whether resting-state basal perfusion levels revealed selective pathophysiology (likely hypo- and hyper-activation) of language-related and executive areas in first-episode psychosis (FEP).

STUDY DESIGN

Basal resting-state perfusion was measured using pseudo-continuous Arterial Spin Labeling (pcASL). Relative cerebral blood flow (rCBF) was compared between 32 FEP and 34 matched healthy comparison (HC) individuals. Structural and functional MRI scans were acquired using a 3T Prisma scanner during the same session.

STUDY RESULTS

Whole-brain comparison of resting rCBF identified 8 clusters with significant between-group differences. Reduced rCBF was found in executive control areas in left and right IFG, right DLPFC, and right parietal cortex. Increased rCBF was found in left and right temporal cortex (including Wernicke's area), and left and right putamen. A positive correlation was observed between auditory hallucination severity and rCBF in the left putamen.

CONCLUSIONS

To the degree that perfusion implies activation, language and auditory processing areas in bilateral temporal lobe and putamen showed pathological hyper-activity, and cognitive control areas (IFG, DLPFC, right parietal) showed pathological hypo-activity in FEP at rest. Pathological basal activity was present across the range of symptom severity, suggesting it may be a common underlying pathology for psychosis that may be targeted with non-invasive brain stimulation to normalize resting activity levels.

Relationships among subclinical psychotic symptoms in young adults over time

BACKGROUND

Subclinical psychotic symptoms are common in the general population and are often benign. However, those that become distressing or persistent may increase risk for the development of a psychotic disorder. Cognitive models have proposed that certain appraisals of hallucinatory experiences can lead to delusional beliefs, particularly if an individual is experiencing negative mood. However, the dynamic relationships among these symptoms are poorly understood. This study examined the longitudinal relationships among subclincal hallucinations, delusional ideation, and depression in a sample of young adults.

METHODS

677 college students completed baseline questionnaires to assess: delusional ideation (Peters Delusions Inventory), hallucinations (Launay-Slade Hallucinations Scale-Extended), and depression (Beck Depression Inventory). These measures were repeated 7, 13, 19, and 25 months later.

RESULTS

Higher baseline severity of hallucinations was strongly predictive of severity of delusions across all future follow-up timepoints, specifically when baseline depression was high. However, the severity of hallucinations did not change over time, nor were they predicted by baseline delusional ideation.

CONCLUSIONS

These findings support the proposal that hallucinations frequently precede more severe delusional ideation, rather than the reverse sequence, particularly when depressive symptoms are present. Such longitudinal relationships provide clues to the underlying mechanisms of psychosis, highlighting one pathway for intervention.

Visual phenomenology in schizophrenia and post-traumatic stress disorder: an exploratory study

BACKGROUND

Visual experiences such as hallucinations are commonly reported by people with psychosis, psychological trauma and dissociative states, although questions remain about their similarities and differences. For diagnostic and therapeutic purposes, clinical research must better delineate and compare the characteristics of these experiences in post-traumatic stress disorder (PTSD) and in schizophrenia.

AIMS

To compare visual phenomena and dissociation in participants with a primary psychotic illness and those with a trauma diagnosis.

METHOD

A quantitative group design study comparing visual phenomena in three participant groups who also have a history of hearing voices: schizophrenia and no trauma history (n = 19), PTSD with dissociation (n = 17) and comorbid schizophrenia and PTSD (n = 20). Validated clinical measures included the North-East Visual Hallucination Interview, PTSD Symptoms Scale Interview, Clinician Administered Dissociative States Scale, Psychotic Symptoms Rating Scales and Positive and Negative Syndrome Scale.

RESULTS

There was a remarkable similarity in visual experiences, including rates of complex visual hallucinations, between the three diagnostic groups. There were no significant differences in the severity or components of distress surrounding the visual experiences. Dissociation predicted visual hallucination severity for the comorbid schizophrenia and PTSD group, but not for PTSD or schizophrenia alone.

CONCLUSIONS

Visual experiences in PTSD can include visual hallucinations that are indistinguishable from those experienced in schizophrenia. Multimodal hallucinations are frequently observed in both schizophrenia and PTSD. A model for visual hallucinations in PTSD is suggested, following two separate neurobiological pathways based on distinct responses to trauma.

Managing Unusual Sensory Experiences in People with First-Episode Psychosis (MUSE FEP): a study protocol for a single-blind parallel-group randomised controlled feasibility trial

INTRODUCTION

Hallucinations (hearing or seeing things that others do not) are a common feature of psychosis, causing significant distress and disability. Existing treatments such as cognitive-behavioural therapy for psychosis (CBTp) have modest benefits, and there is a lack of CBTp-trained staff. Shorter, targeted treatments that focus on specific symptoms delivered by a non-specialist workforce could substantially increase access to treatment.Managing Unusual Sensory Experiences (MUSE) explains why people have hallucinations and helps the person to develop and use coping strategies to reduce distress. MUSE focuses only on hallucinations, and treatment is short (four to six, 1-hour sessions per week). It is a digital intervention, run on National Health Service (NHS) laptops, which provides information about hallucinations in an engaging way, using audio, video and animated content. Crucially, it is designed for use by non-specialist staff like community psychiatric nurses.

METHODS AND ANALYSIS

The study is a two-arm feasibility randomised controlled trial comparing MUSE and treatment as usual (TAU) (n=40) to TAU alone (n=40), recruiting across two NHS Trusts, using 1:1 allocation and blind assessments before and after treatment (2 months) and at follow-up (3 months). Quantitative information on recruitment rates, adherence and completion of outcome assessments will be collected. Qualitative interviews will capture service users' experience of therapy and clinicians' experiences of the training and supervision in MUSE. Clinicians will also be asked about factors affecting uptake, adherence and facilitators/barriers to implementation. Analyses will focus on feasibility outcomes and provide initial estimates of intervention effects. Thematic analysis of the qualitative interviews will assess the acceptability of the training, intervention and trial procedures.

ETHICS AND DISSEMINATION

The trial has received NHS Ethical and Health Research Authority approval. Findings will be disseminated directly to participants and services, as well as through peer-reviewed publications and conference presentations.

TRIAL REGISTRATION NUMBER

ISRCTN16793301.

A narrative review of psychological theories of post-traumatic stress disorder, voice hearing, and other psychotic symptoms

BACKGROUND

Most voice hearers report childhood trauma. Many voice hearers report comorbid post-traumatic stress symptoms and that the content of their voices (auditory verbal hallucinations) is directly (voices repeat phrases spoken by perpetrators) or indirectly (voice content and trauma is thematically similar) related to their trauma. The factors that maintain trauma-related voices are unknown, and there is limited research in this area. This study aimed to identify potential maintaining factors of trauma-related voices by reviewing models of post-traumatic stress disorder (PTSD) and positive symptoms of psychosis.

METHOD

Models of PTSD and positive symptoms were reviewed to identify potential factors that are unique and common to both sets of symptoms.

RESULTS

We reviewed 10 models of PTSD, 4 models of positive symptoms, and 2 trauma-informed models of voice hearing. One model provided a theoretical explanation of different types of trauma-related voices. Twenty-one factors were extracted from 16 theoretical models. No existing model incorporated all these factors.

DISCUSSION

Existing PTSD and positive symptom models present a range of common and unique factors. There may be value in extending existing integrative models to include a broader range of potential factors that could explain different pathways to, and expressions of, trauma-related voices. A future research agenda is presented to investigate how such an extension could lead to more complete individualized case formulations and targeted treatments.

Distinguishing multimodal versus multisensory hallucinations in psychosis: Key definitions and a way forward

The study of hallucinations across multiple senses in psychosis has garnered renewed interest. Recent studies have adopted the term multimodal hallucinations to describe these experiences, yet some appear to be investigating a different, but related, phenomenon. In the current paper, we suggest use of the terms multimodal hallucinations and multisensory hallucinations to categorise distinct events that involve unusual sensory experiences across multiple domains. We propose that the constructs of temporality and relatedness are critical to delineating these experiences, where multimodal hallucinations refer to hallucinations in two or more sensory modes occurring concurrently in time and/or with significant thematic overlaps. Multisensory hallucinations conversely denote similar multisensory experiences, but with no temporal or relatedness constraints. This is accompanied by a decision-making framework for identifying whether a set of unusual perceptual experiences constitutes multimodal hallucinations or otherwise. We conclude by suggesting several priorities for future research, including empirical validation of our proposed model, further investigation of phenomenology, developing appropriate assessment tools and investigating underlying cognitive and other aetiological mechanisms.

5-HT2A receptor dysregulation in a schizophrenia relevant mouse model of NMDA receptor hypofunction

Blockade of N-methyl-D-aspartate receptors (NMDAR) is known to augment cortical serotonin 2A receptors (5-HT2ARs), which is implicated in psychosis. However, the pathways from NMDAR hypofunction to 5-HT2AR up-regulation are unclear. Here we addressed in mice whether genetic deletion of the indispensable NMDAR-subunit Grin1 principally in corticolimbic parvalbumin-positive fast-spiking interneurons, could up-regulate 5-HT2ARs leading to cortical hyper-excitability. First, in vivo local-field potential recording revealed that auditory cortex in Grin1 mutant mice became hyper-excitable upon exposure to acoustic click-train stimuli that release 5-HT in the cortex. This excitability increase was reproduced ex vivo where it consisted of an increased frequency of action potential (AP) firing in layer 2/3 pyramidal neurons of mutant auditory cortex. Application of the 5-HT2AR agonist TCB-2 produced similar results. The effect of click-trains was reversed by the 5-HT2AR antagonist M100907 both in vivo and ex vivo. Increase in AP frequency of pyramidal neurons was also reversed by application of Gαq protein inhibitor BIM-46187 and G protein-gated inwardly-rectifying K⁺ (GIRK) channel activator ML297. In fast-spiking interneurons, 5-HT2AR activation normally promotes GABA release, contributing to decreased excitability of postsynaptic pyramidal neurons, which was missing in the mutants. Moreover, unlike the controls, the GABA_A receptor antagonist (+)-bicuculline had little effect on AP frequency of mutant pyramidal neurons, indicating a disinhibition state. These results suggest that the auditory-induced hyper-excitable state is conferred via GABA release deficits from Grin1-lacking interneurons leading to 5-HT2AR dysregulation and GIRK channel suppression in cortical pyramidal neurons, which could be involved in auditory psychosis.

Visual hallucinations in psychiatry - what aren't we seeing?

OBJECTIVE

To increase awareness of practising clinicians and researchers to the phenomenological distinctions between visual hallucinations and trauma-based, dissociative, visual re-experiencing phenomena seen in psychiatric disease.

CONCLUSIONS

The experience of visual hallucinations is not exclusive to psychotic disorders in psychiatry. Different forms of experiences that resemble visual hallucinations may occur in patients with a trauma background and may potentially affect diagnosis. Given the paucity of literature around the subject, it is imperative that further research aims to characterise the distinction between visual hallucinations in psychosis and visual phenomena associated with trauma.

Network Analysis-Based Disentanglement of the Symptom Heterogeneity in Asian Patients with Schizophrenia: Findings from the Research on Asian Psychotropic Prescription Patterns for Antipsychotics

The symptom heterogeneity of schizophrenia is consistent with Wittgenstein's analogy of a language game. From the perspective of precision medicine, this study aimed to estimate the symptom presentation and identify the psychonectome in Asian patients, using data obtained from the Research on Asian Psychotropic Prescription Patterns for Antipsychotics. We constructed a network structure of the Brief Psychiatric Rating Scale (BPRS) items in 1438 Asian patients with schizophrenia. Furthermore, all the BPRS items were considered to be an ordered categorical variable ranging in value from 1-7. Motor retardation was situated most centrally within the BPRS network structure, followed by depressive mood and unusual thought content. Contrastingly, hallucinatory behavior was situated least centrally within the network structure. Using a community detection algorithm, the BPRS items were organized into positive, negative, and general symptom clusters. Overall, DSM symptoms were not more central than non-DSM symptoms within the symptom network of Asian patients with schizophrenia. Thus, motor retardation, which results from the unmet needs associated with current antipsychotic medications for schizophrenia, may be a tailored treatment target for Asian patients with schizophrenia. Based on these findings, targeting non-dopamine systems (glutamate, γ-aminobutyric acid) may represent an effective strategy with respect to precision medicine for psychosis.

Hallucinations and Other Psychotic Symptoms in Patients with Borderline Personality Disorder

BACKGROUND

Psychotic symptoms in BPD are not uncommon, and they are diverse and phenomenologically similar to those in schizophrenia spectrum disorders. Despite their prevalence in BPD patients, knowledge about the characteristics and severity of hallucinations is limited, especially in modalities other than auditory.

AIM

This review summarises the causes, phenomenology, severity, and treatment options of hallucinations and other psychotic symptoms in BPD.

METHODS

The PubMed database was used with the following key terms: "borderline personality disorder" and 'hallucinations' and "psychotic symptoms". Articles were selected between January 1990 and May 2021. The primary keyword search yielded a total of 545 papers, of which 102 articles met the inclusion criteria and were fully screened. Papers from the primary source reference lists were also screened, assessed for eligibility, and then added to the primary documents where appropriate (n = 143). After the relevance assessment, 102 papers were included in the review. We included adult and adolescent studies to gather more recent reviews on this topic.

RESULTS

Hallucinations are significantly prevalent in BPD, mainly auditory, similar to schizophrenia spectrum disorders. The relationship between hallucinations and depression, anxiety, suicidality, schizotypy, and loneliness in BPD has been discovered but requires more research. Studies for treatment options for hallucinations in BPD are lacking.

CONCLUSION

Recognition of psychotic symptoms in patients with BPD as distinguished psychopathological phenomena instead of diminishing and overlooking them is essential in the clinical assessment and can be useful in predicting complications during treatment. More focused research in this area is needed.

Alteration of power law scaling of spontaneous brain activity in schizophrenia

Nonlinear dynamical analysis has been used to quantify the complexity of brain signal at temporal scales. Power law scaling is a well-validated method in physics that has been used to describe the dynamics of a system in the frequency domain, ranging from noisy oscillation to complex fluctuations. In this research, we investigated the power-law characteristics in a large-scale resting-state fMRI data of schizophrenia and healthy participants derived from Taiwan Aging and Mental Illness cohort. We extracted the power spectral density (PSD) of resting signal by Fourier transform. Power law scaling of PSD was estimated by determining the slope of the regression line fitting to the logarithm of PSD. t-Test was used to assess the statistical difference in power law scaling between schizophrenia and healthy participants. The significant differences in power law scaling were found in six brain regions. Schizophrenia patients have significantly more positive power law scaling (i.e., more homogenous frequency components) at four brain regions: left precuneus, left medial dorsal nucleus, right inferior frontal gyrus, and right middle temporal gyrus and less positive power law scaling (i.e., more dominant at lower frequency range) in bilateral putamen compared with healthy participants. Moreover, significant correlations of power law scaling with the severity of psychosis were found. These findings suggest that schizophrenia has abnormal brain signal complexity linked to psychotic symptoms. The power law scaling represents the dynamical properties of resting-state fMRI signal may serve as a novel functional brain imaging marker for evaluating patients with mental illness.

Evidence for an interrelated cluster of Hallucinatory experiences in the general population: an incidence study

BACKGROUND

Although hallucinations have been studied in terms of prevalence and its associations with psychopathology and functional impairment, very little is known about sensory modalities other than auditory (i.e. haptic, visual and olfactory), as well the incidence of hallucinations, factors predicting incidence and subsequent course.

METHODS

We examined the incidence, course and risk factors of hallucinatory experiences across different modalities in two unique prospective general population cohorts in the same country using similar methodology and with three interview waves, one over the period 1996-1999 (NEMESIS) and one over the period 2007-2015 (NEMESIS-2).

RESULTS

In NEMESIS-2, the yearly incidence of self-reported visual hallucinations was highest (0.33%), followed by haptic hallucinations (0.31%), auditory hallucinations (0.26%) and olfactory hallucinations (0.23%). Rates in NEMESIS-1 were similar (respectively: 0.35%, 0.26%, 0.23%, 0.22%). The incidence of clinician-confirmed hallucinations was approximately 60% of the self-reported rate. The persistence rate of incident hallucinations was around 20-30%, increasing to 40-50% for prevalent hallucinations. Incident hallucinations in one modality were very strongly associated with occurrence in another modality (median OR = 59) and all modalities were strongly associated with delusional ideation (median OR = 21). Modalities were approximately equally strongly associated with the presence of any mental disorder (median OR = 4), functioning, indicators of help-seeking and established environmental risk factors for psychotic disorder.

CONCLUSIONS

Hallucinations across different modalities are a clinically relevant feature of non-psychotic disorders and need to be studied in relation to each other and in relation to delusional ideation, as all appear to have a common underlying mechanism.

Differential Effectiveness of Atypical Antipsychotics on Hallucinations: A Pragmatic Randomized Controlled Trial

BACKGROUND

Most studies investigating antipsychotic effectiveness report either total psychopathology or symptom cluster findings. Studies focusing on a separate symptom, such as hallucinations, a hallmark symptom in schizophrenia, are scarce.Therefore, the current study aims to compare the antihallucinatory effectiveness of 3 pharmacologically different antipsychotics: olanzapine, amisulpride, and aripiprazole.

METHODS

The present study is part of the Bergen-Stavanger-Innsbruck-Trondheim study, a 12-month prospective, randomized, pragmatic antipsychotic drug trial in active-phase schizophrenia spectrum disorders. The primary outcome of the present study was change of hallucinations as measured by item P3 (hallucinatory behavior) from the Positive and Negative Syndrome Scale in the subgroup with hallucinations at baseline. Primary analyses were intention to treat.

RESULTS

A total of 144 participants were included in the study, where 105 (72%) had a score of 3 or more on the Positive and Negative Syndrome Scale P3 item at baseline, indicating the presence of hallucinations (HALL subgroup).In the HALL subgroup, a significantly less reduction of hallucinations was revealed for participants using olanzapine in weeks 12, 26, 39, and 52 when compared with amisulpride and in weeks 26 and 52 when compared with aripiprazole. In subanalyses for participants never exposed to antipsychotic drugs (antipsychotic-naive) and those who had used antipsychotics before entering the study, antihallucinatory differences were revealed only in the latter group.

CONCLUSIONS

A differential antihallucinatory effect of the 3 study drugs was present. The inferior effect of olanzapine seems to be driven by the subgroup of participants exposed to antipsychotic treatment before entering the study.

In the twilight zone: An epidemiological study of sleep-related hallucinations

BACKGROUND

Few studies have investigated hallucinations that occur at the onset/offset of sleep (called hypnagogic/hypnopompic hallucinations; HHHs), despite the fact that their prevalence in the general population is reported to be higher than the prevalence of daytime hallucinations. We utilized data from an epidemiological study to explore the prevalence of HHHs in various modalities. We also investigated phenomenological differences between sleep-related (HHHs) and daytime hallucinations in the auditory modality. We hypothesized that individuals with only HHHs would not differ from controls on a range of mental health and wellbeing measures, but that if they occur together with daytime hallucinations will pose a greater burden on the individual experiencing them. We also hypothesize that HHHs are qualitatively different (i.e. less severe) from daytime hallucinations.

METHODS

This study utilized data from a cross-sectional epidemiological study on the prevalence of hallucinations in the Norwegian general population. The sample (n = 2533) was divided into a control group without hallucinations (n = 2303), a group only experiencing sleep-related hallucinations (n = 62), a group only experiencing daytime hallucinations (n = 57), and a group experiencing both sleep-related as well as daytime hallucinations (n = 111). Prevalence rates were calculated and groups were compared using analyses of variance and chi-square tests where applicable.

RESULTS

The prevalence for HHHs in the auditory domain was found to be 6.8%, whereas 12.3% reported multimodal HHHs, and 32.2% indicated out-of-body experiences at the onset/offset of sleep. Group comparisons of hallucinations in the auditory modality showed that individuals that experienced only auditory HHHs scored significantly (p < 0.05) lower than those who also experienced daytime auditory hallucinations on a range of variables including mental health, anxiety, childhood happiness, and wellbeing. In addition, individuals with only auditory HHHs reported significantly (p < 0.05) less frequent hallucinations, less disturbing hallucinations, more neutral (in terms of content) hallucinations, hallucinations with less influence over their behavior, and less hallucination-related interference with social life compared to those individuals that experience daytime hallucinations. We also found that purely auditory HHHs had a significantly higher age of first onset of hallucinations than the purely daytime and the combined daytime and auditory HHHs groups (28.2 years>20.9 > 19.1).

CONCLUSIONS

Sleep-related hallucinations are common experiences in the general population, with the auditory modality being the least common. They occur mostly in combination with daytime hallucinations. However, some individuals (2.4%) experience only (auditory) sleep-related hallucinations and this group can be seen as more closely related, on a range of health-related factors, to non-hallucinating individuals than individuals who experience daytime hallucinations. Finally, there is a clear need for more research in this field, and ideas for future studies are presented.

Schizotypal personality traits and multisensory integration: An investigation using the McGurk effect

Multisensory integration, the process by which sensory information from different sensory modalities are bound together, is hypothesized to contribute to perceptual symptomatology in schizophrenia, in whom multisensory integration differences have been consistently found. Evidence is emerging that these differences extend across the schizophrenia spectrum, including individuals in the general population with higher levels of schizotypal traits. In the current study, we used the McGurk task as a measure of multisensory integration. We measured schizotypal traits using the Schizotypal Personality Questionnaire (SPQ), hypothesizing that higher levels of schizotypal traits, specifically Unusual Perceptual Experiences and Odd Speech subscales, would be associated with decreased multisensory integration of speech. Surprisingly, Unusual Perceptual Experiences were not associated with multisensory integration. However, Odd Speech was associated with multisensory integration, and this association extended more broadly across the Disorganized factor of the SPQ, including Odd or Eccentric Behaviour. Individuals with higher levels of Odd or Eccentric Behaviour scores also demonstrated poorer lip-reading abilities, which partially explained performance in the McGurk task. This suggests that aberrant perceptual processes affecting individuals across the schizophrenia spectrum may relate to disorganized symptomatology.

RELATE-a randomised controlled feasibility trial of a Relating Therapy module for distressing auditory verbal hallucinations: a study protocol

INTRODUCTION

Auditory verbal hallucinations (AVHs) are associated with distress and reduced functioning. Research suggests that distress is associated with the voice hearer's responding to AVH in a passive and subordinate manner. A novel approach focuses on relating to AVH and teaches assertive responses to AVH using experiential role-plays. A small pilot study found a large effect of this approach on AVH distress but an independent multicentre study is required to ascertain effectiveness across different settings. We aim to estimate the expected effect for a subsequent trial to demonstrate that adding a module of Relating Therapy (RT) to treatment as usual (TAU) is superior to TAU alone in reducing AVH distress. We also test the feasibility of patient recruitment, therapist training, and therapy monitoring in different psychological and psychiatric outpatient facilities in Germany.

METHODS AND ANALYSIS

We will recruit 75 patients diagnosed with a schizophrenia spectrum disorder and persistent distressing AVH across four sites. Patients will be randomised to receive either 16 sessions of RT plus TAU or TAU alone within a 5-month period. Randomisation will be stratified by sites. Single-blind assessments will take place at baseline, at 5 months (T1) and at 9 months (T2). The primary outcome is the distress factor score of the AVH subscale of the Psychotic Symptoms Rating Scale at T2 adjusted for the baseline value. Secondary outcomes are change in depressive symptoms, quality of life, time spent in structured activities as well as negative relating to voices and to other people.

ETHICS AND DISSEMINATION

The trial has received ethical approval from the German Psychological Society Ethics Committee. The trial results will be disseminated through conference presentations, peer-reviewed publications and social media.

TRIAL REGISTRATION NUMBER

ClinicalTrials.gov Registry (NCT04578314).

Hearing Voices and Seeing Things: Symptoms of Anxiety Misconstrued as Evidence of Schizophrenia in an Adolescent

A patient's complaint of "hearing voices" or "seeing things" or of similar perceptual abnormalities leaves the clinician with 2 decisions: (1) Is the patient actually experiencing a hallucination, or does the complaint reflect a different mental experience, ranging from outright fabrication to the misinterpretation or mislabeling of vivid thoughts and emotions? (2) How should the experience reported by the patient, whether determined to be a hallucination or not, be understood in the context of the patient's entire history and mental state? We report the case of a 16-year-old whose cartoon-like hallucinations had led to the diagnosis of schizophrenia and had directed attention of the patient, her parents, and her clinicians away from critical issues of anxiety, depression, learning difficulties, and traumatic school experiences. This case illustrates how the diagnosis of schizophrenia can be driven by the prominence and vividness of psychotic-like symptoms reported by a patient, the expectation that patients' chief complaints must be directly and immediately addressed, insufficient attention to collateral information, and the distortions of a "checklist" approach to psychiatric diagnosis driven by the criteria in the Diagnostic and Statistical Manual of Mental Disorders, insurers, and the properties of electronic medical records. Given the consequences of either underdiagnosing or overdiagnosing schizophrenia, and the current lack of validated objective tests to assist with this diagnosis, clinicians are obligated to perform a thorough clinical assessment of such patients, including a probing exploration of the patient's mental state and a systematic collection of collateral information.

Multimodal versus unimodal auditory hallucinations in clinical practice: Clinical characteristics and treatment outcomes

Psychological treatments for hallucinations typically target auditory verbal hallucinations (AVH) but neglect the influence of hallucinations in other sensory modalities. This study compared the baseline clinical characteristics and therapeutic outcomes (following brief Coping Strategy Enhancement) of adult clients (N = 100) with multimodal or unimodal (auditory) hallucinations attending an outpatient service for distressing AVH. The results showed that 72.1% of clients reported multimodal hallucinations in the past month. Group comparisons of most baseline clinical characteristics (AVH features, beliefs about AVH, number of traumatic events, personal and social functioning, negative affect) were non-significant. However, in the subgroup (N = 65) reporting ongoing effects of traumatic events, those with multimodal hallucinations reported significantly higher posttraumatic stress symptoms (d = 0.62). Notably, both multimodal and unimodal hallucination groups showed improvement in AVH distress and frequency post-treatment, but group differences in treatment outcomes were not significant. These findings, in a naturalistic service setting, confirm that multimodal hallucinations are common in people seeking help for distressing AVH and may be associated with higher levels of posttraumatic stress symptoms. Importantly, they also suggest that psychological therapy may be suitable and effective for clients experiencing AVH - irrespective of the presence of hallucinations in other sensory modalities.

The Relationship Between Multisensory Temporal Processing and Schizotypal Traits

Recent literature has suggested that deficits in sensory processing are associated with schizophrenia (SCZ), and more specifically hallucination severity. The DSM-5's shift towards a dimensional approach to diagnostic criteria has led to SCZ and schizotypal personality disorder (SPD) being classified as schizophrenia spectrum disorders. With SCZ and SPD overlapping in aetiology and symptomatology, such as sensory abnormalities, it is important to investigate whether these deficits commonly reported in SCZ extend to non-clinical expressions of SPD. In this study, we investigated whether levels of SPD traits were related to audiovisual multisensory temporal processing in a non-clinical sample, revealing two novel findings. First, less precise multisensory temporal processing was related to higher overall levels of SPD symptomatology. Second, this relationship was specific to the cognitive-perceptual domain of SPD symptomatology, and more specifically, the Unusual Perceptual Experiences and Odd Beliefs or Magical Thinking symptomatology. The current study provides an initial look at the relationship between multisensory temporal processing and schizotypal traits. Additionally, it builds on the previous literature by suggesting that less precise multisensory temporal processing is not exclusive to SCZ but may also be related to non-clinical expressions of schizotypal traits in the general population.

Advancing clinical response characterization to frontotemporal transcranial direct current stimulation with electric field distribution in patients with schizophrenia and auditory hallucinations: a pilot study

Transcranial direct current stimulation (tDCS) has been proposed as a therapeutic option for treatment-resistant auditory verbal hallucinations (AVH) in schizophrenia. In such cases, repeated sessions of tDCS are delivered with the anode over the left prefrontal cortex and the cathode over the left temporoparietal junction. Despite promising findings, the clinical response to tDCS is highly heterogeneous among patients. Here, we explored baseline differences between responders and nonresponders to frontotemporal tDCS using electric field modeling. We hypothesized that responders would display different tDCS-induced electric field strength in the brain areas involved in AVH compared to nonresponders.Using baseline structural MRI scans of 17 patients with schizophrenia and daily AVH who received 10 sessions of active frontotemporal tDCS, we constructed individual realistic whole brain models estimating electric field strength. Electric field maps were compared between responders (n = 6) and nonresponders to tDCS (n = 11) using an independent two-sample t test. Clinical response was defined as at least a 50% decrease of AVH 1 month after the last tDCS session.Results from the electric field map comparison showed that responders to tDCS displayed higher electric field strength in the left transverse temporal gyrus at baseline compared to nonresponders (T = 2.37; p = 0.016; 32 voxels).These preliminary findings suggested that the strength of the tDCS-induced electric field reaching the left transverse temporal gyrus could play an important role in the response to frontotemporal tDCS. In addition, this work suggests the interest of using electric field modeling to individualize tDCS and increase response rate.

White Matter Microstructural Differences between Hallucinating and Non-Hallucinating Schizophrenia Spectrum Patients

The relation between auditory verbal hallucinations (AVH) and white matter has been studied, but results are still inconsistent. This inconsistency may be related to having only a single time-point of AVH assessment in many studies, not capturing that AVH severity fluctuates over time. In the current study, AVH fluctuations were captured by utilizing a longitudinal design and using repeated (Positive and Negative Symptoms Scale) PANSS questionnaire interviews over a 12 month period. We used a Magnetic Resonance Diffusion Tensor Imaging (MR DTI) sequence and tract-based spatial statistics (TBSS) to explore white matter differences between two subtypes of schizophrenia patients; 44 hallucinating (AVH+) and 13 non-hallucinating (AVH-), compared to 13 AVH- matched controls and 44 AVH+ matched controls. Additionally, we tested for hemispheric fractional anisotropy (FA) asymmetry between the groups. Significant widespread FA-value reduction was found in the AVH+ group in comparison to the AVH- group. Although not significant, the extracted FA-values for the control group were in between the two patient groups, for all clusters. We also found a significant difference in FA-asymmetry between the AVH+ and AVH- groups in two clusters, with significantly higher leftward asymmetry in the AVH- group. The current findings suggest a possible qualitative difference in white matter integrity between AVH+ and AVH- patients. Strengths and limitations of the study are discussed.

The Staff Views About Assessing Voices Questionnaire: Piloting a Novel Socratic Method of Evaluating and Training Multidisciplinary Staff's Cognitive Assessment of Patients' Distressing Voices

Cognitive features of auditory hallucinations (voices) have important clinical significance and their assessment is vital for cognitive behavior therapy to be more widely deployed by multidisciplinary staff. Using a new Socratic instrument-The Staff Views About Assessing Voices Questionnaire (SVAVQ)-we surveyed a community inpatient rehabilitation multidisciplinary workforce's (N = 50) assessment and attitude toward asking cognitive questions about patients' voices. We found that there were many clinically important gaps in what staff asked about in relation to cognitive features of voices. We identified a range of beliefs the staff hold that may prevent assessment of voice cognitive features. However, after attending the Socratic SVAVQ interview, 84% of staff said they planned to ask patients more questions about cognitive features of patients' voices. Research could now test if other psychosis services neglect the assessment of important cognitive features of patients' voices and if staff Socratic questioning improves their cognitive assessments.

The Phenomenology and Neurobiology of Visual Distortions and Hallucinations in Schizophrenia: An Update

Schizophrenia is characterized by visual distortions in ~60% of cases, and visual hallucinations (VH) in ~25-50% of cases, depending on the sample. These symptoms have received relatively little attention in the literature, perhaps due to the higher rate of auditory vs. visual hallucinations in psychotic disorders, which is the reverse of what is found in other neuropsychiatric conditions. Given the clinical significance of these perceptual disturbances, our aim is to help address this gap by updating and expanding upon prior reviews. Specifically, we: (1) present findings on the nature and frequency of VH and distortions in schizophrenia; (2) review proposed syndromes of VH in neuro-ophthalmology and neuropsychiatry, and discuss the extent to which these characterize VH in schizophrenia; (3) review potential cortical mechanisms of VH in schizophrenia; (4) review retinal changes that could contribute to VH in schizophrenia; (5) discuss relationships between findings from laboratory measures of visual processing and VH in schizophrenia; and (6) integrate findings across biological and psychological levels to propose an updated model of VH mechanisms, including how their content is determined, and how they may reflect vulnerabilities in the maintenance of a sense of self. In particular, we emphasize the potential role of alterations at multiple points in the visual pathway, including the retina, the roles of multiple neurotransmitters, and the role of a combination of disinhibited default mode network activity and enhanced state-related apical/contextual drive in determining the onset and content of VH. In short, our goal is to cast a fresh light on the under-studied symptoms of VH and visual distortions in schizophrenia for the purposes of informing future work on mechanisms and the development of targeted therapeutic interventions.

The Strasbourg Visual Scale: A Novel Method to Assess Visual Hallucinations

The experience of oneself in the world is based on sensory afferences, enabling us to reach a first-perspective perception of our environment and to differentiate oneself from the world. Visual hallucinations may arise from a difficulty in differentiating one's own mental imagery from externally-induced perceptions. To specify the relationship between hallucinations and the disorders of the self, we need to understand the mechanisms of hallucinations. However, visual hallucinations are often under reported in individuals with psychosis, who sometimes appear to experience difficulties describing them. We developed the "Strasbourg Visual Scale (SVS)," a novel computerized tool that allows us to explore and capture the subjective experience of visual hallucinations by circumventing the difficulties associated with verbal descriptions. This scale reconstructs the hallucinated image of the participants by presenting distinct physical properties of visual information, step-by-step to help them communicate their internal experience. The strategy that underlies the SVS is to present a sequence of images to the participants whose choice at each step provides a feedback toward re-creating the internal image held by them. The SVS displays simple images on a computer screen that provide choices for the participants. Each step focuses on one physical property of an image, and the successive choices made by the participants help them to progressively build an image close to his/her hallucination, similar to the tools commonly used to generate facial composites. The SVS was constructed based on our knowledge of the visual pathways leading to an integrated perception of our environment. We discuss the rationale for the successive steps of the scale, and to which extent it could complement existing scales.

Illusions, hallucinations, and visual snow

Illusions and hallucinations are commonly encountered in both daily life and clinical practice. In this chapter, we review definitions and possible underlying mechanisms of these phenomena and then review what is known about specific conditions that are associated with them, including ophthalmic causes, migraine, epilepsy, Parkinson's disease, and schizophrenia. We then discuss specific syndromes including the Charles Bonnet syndrome, visual snow syndrome, Alice in Wonderland syndrome, and peduncular hallucinosis. The scientific study of illusions and hallucinations has contributed significantly to our understanding of how eye and brain process vision and contribute to perception. Important concepts are the distinction between topologic and hodologic mechanisms underlying hallucinations and the involvement of attentional networks. This chapter examines the various ways in which pathological illusions and hallucinations might arise in relation to the phenomenology and known pathology of the various conditions associated with them.