Auditory hallucinations in a cross-diagnostic sample of psychotic disorder patients: a descriptive, cross-sectional study

Targeting the superior temporal gyrus with real-time fMRI neurofeedback: A pilot study of the indirect effects on self-referential processes in schizophrenia

BACKGROUND

Individuals with schizophrenia (SZ) and auditory hallucinations (AHs) display a distorted sense of self and self-other boundaries. Alterations of activity in midline cortical structures such as the prefrontal cortex (mPFC) and anterior cingulate cortex (ACC) during self-reference as well as in the superior temporal gyrus (STG) have been proposed as neuromarkers of SZ and AHs.

METHODS

In this randomized, participant-blinded, sham-controlled trial, 22 adults (18 males) with SZ spectrum disorders (SZ or schizoaffective disorder) and frequent medication-resistant AHs received one session of real-time fMRI neurofeedback (NFB) either from the STG (n = 11; experimental group) or motor cortex (n = 11; control group). During NFB, participants were instructed to upregulate their STG activity by attending to pre-recorded sentences spoken in their own voice and downregulate it by ignoring unfamiliar voices. Before and after NFB, participants completed a self-reference task where they evaluated if trait adjectives referred to themselves (self condition), Abraham Lincoln (other condition), or whether adjectives had a positive valence (semantic condition). FMRI activation analyses of self-reference task data tested between-group changes after NFB (self>semantic, post>pre-NFB, experimental>control). Analyses were pre-masked within a self-reference network.

RESULTS

Activation analyses revealed significantly (p < 0.001) greater activation increase in the experimental, compared to the control group, after NFB within anterior regions of the self-reference network (mPFC, ACC, superior frontal cortex).

CONCLUSIONS

STG-NFB was associated with activity increase in the mPFC, ACC, and superior frontal cortex during self-reference. Modulating the STG is associated with activation changes in other, not-directly targeted, regions subserving higher-level cognitive processes associated with self-referential processes and AHs psychopathology in SZ.

CLINICALTRIALS

GOV: Rt-fMRI Neurofeedback and AH in Schizophrenia; https://clinicaltrials.gov/study/NCT03504579.

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.

Auditory hallucinations, childhood sexual abuse, and limbic gray matter volume in a transdiagnostic sample of people with psychosis

Childhood sexual abuse (CSA) is a potentially unique risk factor for auditory hallucinations (AH), but few studies have examined the moderating effects of sex or the association of CSA with limbic gray matter volume (GMV) in transdiagnostic samples of people with psychotic disorders. Here we found that people with psychotic disorders reported higher levels of all surveyed maltreatment types (e.g., physical abuse) than healthy controls, but people with psychotic disorders with AH (n = 41) reported greater CSA compared to both those without AH (n = 37; t = -2.21, p = .03) and controls (n = 37; t = -3.90, p < .001). Among people with psychosis, elevated CSA was most pronounced among females with AH (sex × AH status: F = 4.91, p = .009), held controlling for diagnosis, medications, and other maltreatment (F = 3.88, p = .02), and correlated with the current severity of AH (r = .26, p = .03) but not other symptoms (p's > .16). Greater CSA among patients related to larger GMV of the left amygdala accounting for AH status, diagnosis, medications, and other maltreatment (t = 2.12, p = .04). Among people with psychosis, females with AH may represent a unique subgroup with greater CSA. Prospective high-risk studies integrating multiple measures of maltreatment and brain structure/function may help elucidate the mechanisms linking CSA with amygdala alterations and AH.

Clinical phenotypes of five patients with psychotic disorders carrying rare schizophrenia-associated loss-of-function variants

The Schizophrenia Exome Meta-Analysis (SCHEMA) consortium identified 10 genes in which loss-of-function (LoF) variants are highly associated with schizophrenia (SZ). In a well-characterized sample of 988 patients with psychotic disorders, we investigated whether patients bearing a SCHEMA variant presented with unusual or unique signs, symptoms, or course of illness. We identified 5 patients who carried a LoF variant in a SCHEMA gene, each in a different gene. None of the patients with a SCHEMA variant had unique symptoms. However, compared to the average of patients in the sample, all of the patients with a SCHEMA variant had earlier onset of any mental illness and more hospitalizations. Also, among SCHEMA carriers, 80 % were treated with clozapine, 60 % with ECT, all with either clozapine or ECT and 40 % with both clozapine and ECT, compared to only 2 % treated with clozapine and 18 % treated with ECT in the comparison group of patients without SCHEMA variants. All 5 patients with a SCHEMA variant had polysubstance abuse, and all had attempted suicide. Fewer than half had such presentations in the group without SCHEMA variants. In this small sample, SCHEMA variants appear to be associated with earlier onset, less favorable response to standard first-line treatments, and more severe illness, but not unique presentations of illness.

Psychotic symptoms in bipolar disorder and their impact on the illness: A systematic review

BACKGROUND

Lifetime psychotic symptoms are present in over half of the patients with bipolar disorder (BD) and can have an adverse effect on its course, outcome, and treatment. However, despite a considerable amount of research, the impact of psychotic symptoms on BD remains unclear, and there are very few systematic reviews on the subject.

AIM

To examine the extent of psychotic symptoms in BD and their impact on several aspects of the illness.

METHODS

The Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines were followed. An electronic literature search of six English-language databases and a manual search was undertaken to identify published articles on psychotic symptoms in BD from January 1940 to December 2021. Combinations of the relevant Medical Subject Headings terms were used to search for these studies. Articles were selected after a screening phase, followed by a review of the full texts of the articles. Assessment of the methodological quality of the studies and the risk of bias was conducted using standard tools.

RESULTS

This systematic review included 339 studies of patients with BD. Lifetime psychosis was found in more than a half to two-thirds of the patients, while current psychosis was found in a little less than half of them. Delusions were more common than hallucinations in all phases of BD. About a third of the patients reported first-rank symptoms or mood-incongruent psychotic symptoms, particularly during manic episodes. Psychotic symptoms were more frequent in bipolar type I compared to bipolar type II disorder and in mania or mixed episodes compared to bipolar depression. Although psychotic symptoms were not more severe in BD, the severity of the illness in psychotic BD was consistently greater. Psychosis was usually associated with poor insight and a higher frequency of agitation, anxiety, and hostility but not with psychiatric comorbidity. Psychosis was consistently linked with increased rates and the duration of hospitalizations, switching among patients with depression, and poorer outcomes with mood-incongruent symptoms. In contrast, psychosis was less likely to be accompanied by a rapid-cycling course, longer illness duration, and heightened suicidal risk. There was no significant impact of psychosis on the other parameters of course and outcome.

CONCLUSION

Though psychotic symptoms are very common in BD, they are not always associated with an adverse impact on BD and its course and outcome.

Auditory verbal hallucinations as ictal phenomena in a patient with drug-resistant epilepsy

PURPOSE

The presence of verbal auditory hallucinations is often associated with psychotic disorders and rarely is considered as an ictal phenomena. The aim of this paper is to describe the anatomical structures involved in the genesis of this ictal symptom during epileptic seizures and direct cortical stimulation using stereo encephalography (SEEG).

METHOD

The case is of a 31-year-old right-handed female, bilateral speech representation, schizophrenia and with drug-resistant epilepsy and focal aware sensory seizures characterized by ictal verbal auditory hallucinations. She was implanted with depth electrodes, and she was monitored using SEEG recordings.

RESULTS

She had focal aware sensory seizures characterized by verbal auditory hallucinations, with the following features: hearing numerous voices (both male and/or female), talking at the same time (not able to distinguish how many). The voices were inside her head, consisted of negative content, and lasted up to two minutes. Some of her focal aware sensory seizures evolved to focal motor seizures and rarely progressed to bilateral tonic clonic seizures. Her neurological examination, her brain MRI and her interictal SPECT were unremarkable. Her PET scan identified mild hypo metabolism over the right temporal and right frontal lobes. Her neuropsychological evaluation showed language laterality undetermined but her functional MRI showed bilateral language representation. On her video-EEG, three seizures were captured with a right posterior temporal onset. A subsequent SEEG showed thirteen typical seizures originating from the posterior temporal neocortical region. The cortical stimulation of the right posterior temporo-parietal neocortical region and right amygdala triggered her typical phenomena, which was multiple voices, inside her head, speaking in the second person, negative content, unable to identify gender, in English, and no side lateralization.

CONCLUSION

Verbal auditory hallucinations should be analyzed carefully because they can be part of the seizure presentation. Our case supports the localization of these hallucinations in the right posterior neocortical temporal regions.

Investigation of motor self-monitoring deficits in schizophrenia with passivity experiences using a novel modified joint position matching paradigm

Numerous studies have identified deficits in the self-monitoring system that are associated with schizophrenia. However, the tasks used in the few previous studies generally involved complex cognitive processes and rarely compared between patients with and without passivity experiences (PE). Here, we examined the deficits in internal motor predictive representation in patients with and without PE, and in healthy controls using a novel paradigm which involved minimal cognitive processes. All participants completed a modified joint position matching (mJPM) task, in which they were required to replicate a voluntary, a passive verbally-cued, and a passive tactile-cued movement under blinded conditions. The absolute difference between the target spot and replicated spot was measured and compared. We hypothesised that if there was a failure in the internal motor predictive representation, patients with PEs would replicate less accurately in the voluntary condition, relative to passive conditions while the healthy controls would be more accurate, and, therefore, significant interactions between groups and conditions would be revealed. Both healthy controls and patients without PEs replicated more accurately in the voluntary condition compared with the passive conditions. The patients with PEs were less accurate in the voluntary condition compared with the passive tactile condition. A significant interaction was observed between patients with vs. without PEs × voluntary vs. passive tactile conditions. The findings suggested the relationship between deficits in motor self-monitoring in the prediction process and PEs, thus showing the need to highlight the link between motor performance and PEs.

Altered dynamic functional connectivity of auditory cortex and medial geniculate nucleus in first-episode, drug-naïve schizophrenia patients with and without auditory verbal hallucinations

BACKGROUND AND OBJECTIVE

As a key feature of schizophrenia, auditory verbal hallucination (AVH) is causing concern. Altered dynamic functional connectivity (dFC) patterns involving in auditory related regions were rarely reported in schizophrenia patients with AVH. The goal of this research was to find out the dFC abnormalities of auditory related regions in first-episode, drug-naïve schizophrenia patients with and without AVH using resting state functional magnetic resonance imaging (rs-fMRI).

METHODS

A total of 107 schizophrenia patients with AVH, 85 schizophrenia patients without AVH (NAVH) underwent rs-fMRI examinations, and 104 healthy controls (HC) were matched. Seed-based dFC of the primary auditory cortex (Heschl's gyrus, HES), auditory association cortex (AAC, including Brodmann's areas 22 and 42), and medial geniculate nucleus (MGN) was conducted to build a whole-brain dFC diagram, then inter group comparison and correlation analysis were performed.

RESULTS

In comparison to the NAVH and HC groups, the AVH group showed increased dFC from left ACC to the right middle temporal gyrus and right middle occipital gyrus, decreased dFC from left HES to the left superior occipital gyrus, left cuneus gyrus, left precuneus gyrus, decreased dFC from right HES to the posterior cingulate gyrus, and decreased dFC from left MGN to the bilateral calcarine gyrus, bilateral cuneus gyrus, bilateral lingual gyrus. The Auditory Hallucination Rating Scale (AHRS) was significantly positively correlated with the dFC values of cluster 1 (bilateral calcarine gyrus, cuneus gyrus, lingual gyrus, superior occipital gyrus, precuneus gyrus, and posterior cingulate gyrus) using left AAC seed, cluster 2 (right middle temporal gyrus and right middle occipital gyrus) using left AAC seed, cluster 1 (bilateral calcarine gyrus, cuneus gyrus, lingual gyrus, superior occipital gyrus, precuneus gyrus and posterior cingulate gyrus) using right AAC seed and cluster 2 (posterior cingulate gyrus) using right HES seed in the AVH group. In both AVH and NAVH groups, a significantly negative correlation is also found between the dFC values of cluster 2 (posterior cingulate gyrus) using the right HES seed and the PANSS negative sub-scores.

CONCLUSIONS

The present findings demonstrate that schizophrenia patients with AVH showed multiple abnormal dFC regions using auditory related cortex and nucleus as seeds, particularly involving the occipital lobe, default mode network (DMN), and middle temporal lobe, implying that the different dFC patterns of auditory related areas could provide a neurological mechanism of AVH in schizophrenia.

Auditory hallucinations across the psychosis spectrum: Evidence of dysconnectivity involving cerebellar and temporal lobe regions

BACKGROUND

Auditory hallucinations (AH) are typically associated with schizophrenia (SZ), but they are also prevalent in bipolar disorder (BD). Despite the large body of research on the neural correlates of AH in SZ, the pathophysiology underlying AH remains unclear. Few studies have examined the neural substrates associated with propensity for AH in BD. Investigating AH across the psychosis spectrum has the potential to inform about the neural signature associated with the trait of AH, irrespective of psychiatric diagnosis.

METHODS

We compared resting state functional magnetic resonance imaging data in psychosis patients with (n = 90 AH; 68 SZ, 22 BD) and without (n = 55 NAH; 16 SZ, 39 BD) lifetime AH. We performed region of interest (ROI)-to-ROI functional connectivity (FC) analysis using 91 cortical, 15 subcortical, and 26 cerebellar atlas-defined regions. The primary aim was to identify FC differences between patients with and without lifetime AH. We secondarily examined differences between AH and NAH within each diagnosis.

RESULTS

Compared to the NAH group, patients with AH showed higher FC between cerebellum and frontal (left precentral gyrus), temporal [right middle temporal gyrus (MTG), left inferior temporal gyrus (ITG), left temporal fusiform gyrus)], parietal (bilateral superior parietal lobules), and subcortical (left accumbens, left palldium) brain areas. AH also showed lower FC between temporal lobe regions (between right ITG and right MTG and bilateral superior temporal gyri) relative to NAH.

CONCLUSIONS

Our findings suggest that dysconnectivity involving the cerebellum and temporal lobe regions may be common neurofunctional elements associated with AH propensity across the psychosis spectrum. We also found dysconnectivity patterns that were unique to lifetime AH within SZ or bipolar psychosis, suggesting both common and distinct mechanisms underlying AH pathophysiology in these disorders.

The influence of romantic relationships on mental wellbeing for people who experience psychosis: A systematic review

PURPOSE

Whilst it is generally accepted that supportive relationships facilitate recovery from psychosis, much less is known about the role of romantic relationships in people with psychosis. This review aimed to synthesise quantitative literature regarding the impact of romantic relationships on the mental health and general wellbeing of people who experience psychosis.

METHOD

A systematic review of electronic databases (PsychINFO, PubMed, Web of Science) was carried out using search terms relating to psychosis and romantic relationships. Papers were selected for inclusion by independent reviewers. Quality assessment was completed and a narrative synthesis produced.

RESULTS

Fifty-eight studies reporting the association between romantic relationships and psychotic symptoms, depression, posttraumatic stress disorder, suicidality, quality of life, satisfaction with life and self-esteem were included. Results were mixed but indicated having a romantic partner may be associated with reduced positive and negative symptoms of psychosis, but increased depressive symptoms. Tentative explanations for these findings, such as functioning prior to onset of psychosis, social support and relationship quality are explored.

CONCLUSION

Findings highlight the importance of this often-overlooked area in clinical practice. Studies with robust design, which specifically aim to understand the relationship between romantic relationships and wellbeing for people who experience psychosis are needed.

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.

Electroencephalographic Microstates in Schizophrenia and Bipolar Disorder

Schizophrenia (SCH) and bipolar disorder (BD) are characterized by many types of symptoms, damaged cognitive function, and abnormal brain connections. The microstates are considered to be the cornerstones of the mental states shown in EEG data. In our study, we investigated the use of microstates as biomarkers to distinguish patients with bipolar disorder from those with schizophrenia by analyzing EEG data measured in an eyes-closed resting state. The purpose of this article is to provide an electron directional physiological explanation for the observed brain dysfunction of schizophrenia and bipolar disorder patients. Methods: We used microstate resting EEG data to explore group differences in the duration, coverage, occurrence, and transition probability of 4 microstate maps among 20 SCH patients, 26 BD patients, and 35 healthy controls (HCs). Results: Microstate analysis revealed 4 microstates (A-D) in global clustering across SCH patients, BD patients, and HCs. The samples were chosen to be matched. We found the greater presence of microstate B in BD patients, and the less presence of microstate class A and B, the greater presence of microstate class C, and less presence of D in SCH patients. Besides, a greater frequent switching between microstates A and B and between microstates B and A in BD patients than in SCH patients and HCs and less frequent switching between microstates C and D and between microstates D and C in BD patients compared with SCH patients. Conclusion: We found abnormal features of microstate A, B in BD patients and abnormal features of microstate A, B, C, and D in SCH patients. These features may indicate the potential abnormalities of SCH patients and BD patients in distributing neural resources and influencing opportune transitions between different states of activity.

Prevalence and Factors Associated with Suicidal Ideation in Institutionalized Patients with Schizophrenia

Purpose

The shorter life expectancy and increased risk of suicide in patients with schizophrenia have been well documented. However, study outcomes on suicidality in this special population have been few to date. This study investigated the prevalence and factors associated with suicidal ideation in a population of institutionalized patients with schizophrenia.

Methods

Two hundred fifty-six patients with schizophrenia between the age of 18 and 65 years were randomly recruited. This cross-sectional study utilised the Calgary Depression Scale for Schizophrenia (CDSS), the Positive and Negative Syndrome Scale (PANSS) and the Psychotic Symptom Rating Scale (PSYRATS-AH). Univariate analysis was performed using an independent t-test or chi-square test, followed by binary logistic regression to determine the factors associated with increased suicidal risks.

Results

The socio-demographic factors associated with suicidal ideation included level of education (p=0.039); secondary-level education (OR=5.76, 95% CI:1.49, 22.34, p=0.011) and tertiary-level education (OR=9.30, 95% CI: 1.80, 48.12, p=0.008) posed a greater risk. A history of attempted suicide (OR=2.09, 95% CI: 1.01, 4.36, p=0.049) and the presence of co-morbid physical illnesses (OR=2.07, 95% CI: 1.02, 4.21, p=0.044) were also found to be associated with a suicidal ideation. Other significant factors associated with suicidal thoughts were concurrent depression (OR=9.68, 95% CI: 3.74, 25.05, p<0.001) and a higher PSYRATS score in emotional characteristics of auditory hallucinations (OR=1.13, 95% CI: 1.06, 1.21, p<0.001).

Conclusion

Suicide in schizophrenia appears to be more closely associated with certain socio-demographic factors and affective symptoms. Appropriate screening and treatment addressing these challenges must be emphasized if suicidal thoughts and actions are to be reduced.

A Review of Multimodal Hallucinations: Categorization, Assessment, Theoretical Perspectives, and Clinical Recommendations

Hallucinations can occur in different sensory modalities, both simultaneously and serially in time. They have typically been studied in clinical populations as phenomena occurring in a single sensory modality. Hallucinatory experiences occurring in multiple sensory systems-multimodal hallucinations (MMHs)-are more prevalent than previously thought and may have greater adverse impact than unimodal ones, but they remain relatively underresearched. Here, we review and discuss: (1) the definition and categorization of both serial and simultaneous MMHs, (2) available assessment tools and how they can be improved, and (3) the explanatory power that current hallucination theories have for MMHs. Overall, we suggest that current models need to be updated or developed to account for MMHs and to inform research into the underlying processes of such hallucinatory phenomena. We make recommendations for future research and for clinical practice, including the need for service user involvement and for better assessment tools that can reliably measure MMHs and distinguish them from other related phenomena.

On the phenomenology of auditory verbal hallucinations in affective and non-affective psychosis

Phenomenological comparisons of auditory verbal hallucinations (AVHs) in affective versus non-affective psychosis have not been adequately documented. The current study aimed to: a) comprehensively describe AVH phenomenology by diagnosis and mood state, b) investigate significant predictors of voice-related distress and functional impairment, and c) conduct qualitative thematic analysis of participants' experiences. Participants were diagnosed with: a) bipolar disorder (n = 31), b) major depressive disorder (n = 34), c) schizophrenia (n = 50), or d) schizoaffective disorder (n = 26). Current voice-hearers were also subdivided into prevailing mood states: a) euthymic (n = 23), b) depressed (n = 51), or c) mania-mixed (n = 12). An in-depth, semi-structured interview was conducted, accompanied by mixed-methods analyses. Of the 34 AVH characteristics, significant group differences across diagnoses were identified only for frequency, number of voices, form of address, perceived location, level of conviction, beliefs regarding origin, and functional interference. Random forests modelling (RFM) showed experienced distress and functional interference were best predicted by discrete AVH variables. Qualitative thematic analysis revealed first-order themes: a) content, b) form, c) function, and d) non-voice. There were more similarities than differences in the phenomenology of AVHs across diagnoses, yet significant predictors of voice-related distress and functional impairment differed across affective and non-affective psychosis. This has important nosological and therapeutic applications.

Resting state auditory-language cortex connectivity is associated with hallucinations in clinical and biological subtypes of psychotic disorders

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Transdiagnostic evidence for neural disruption in psychotic hallucinations.

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Hallucinations associated increased connectivity in auditory association cortex.

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Brain regions for auditory-verbal language comprehension linked to hallucinations.

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Interhemispheric connectivity alterations related to subgroup-specific findings.

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Hallucinations link to auditory rs-connectivity tested in 243 psychosis patients.

Background

Auditory hallucinations are prevalent across the major psychotic disorders, but their underlying mechanism is poorly understood. Limited prior work supports a hypothesis of altered auditory/language brain systems. To more definitively assess this, we examined whether alterations in resting state connectivity of auditory and language cortices are associated with hallucination severity in a large sample of individuals in the schizo-bipolar spectrum.

Methods

Whole brain resting state connectivity of auditory and language cortex (primary auditory cortex, unimodal auditory association cortex, Wernicke’s area [speech and heteromodal association cortex] and Broca’s area [speech production motor]) was evaluated for 243 subjects with schizophrenia, schizoaffective, or bipolar disorder with psychosis and 186 healthy controls from the Bipolar Schizophrenia Network on Intermediate Phenotypes (B-SNIP) study. Regression analyses were conducted to evaluate whether resting state connectivity of auditory and language cortex was a significant predictor of current overall hallucination severity (information about specific modality of hallucinations experienced was not available).

Results

Increased connectivity between lower and higher order regions of left temporal-parietal auditory/language processing cortex was associated with worse hallucination severity for all psychosis patients. Additionally, within bipolar subjects, increased interhemispheric connectivity between higher order temporal-parietal auditory/language regions was related to greater hallucination severity. When patients were categorized by B-SNIP biomarker-based Biotype groups, interhemispheric connectivity between left auditory association cortex and right core auditory cortex was related to greater hallucination severity for Biotype 1 patients. Exploratory analyses resulted in different patterns of connectivity of auditory/language cortex in patients and controls, unrelated to current hallucination severity.

Conclusions

Although the findings cannot be precisely attributed to auditory hallucination severity or possible differences in such experiences between groups, increased connectivity among the left hemisphere auditory and receptive language cortex may represent a significant factor contributing to hallucination severity across psychotic disorders, and additional subgroup specific connectivity alterations may also be present.

Assessing Voice Hearing in Trauma Spectrum Disorders: A Comparison of Two Measures and a Review of the Literature

Voice hearing (VH) can occur in trauma spectrum disorders (TSD) such as posttraumatic stress disorder (PTSD) and dissociative disorders. However, previous estimates of VH among individuals with TSD vary widely. In this study, we sought to better characterize the rate and phenomenology of VH in a sample of 70 women with TSD related to childhood abuse who were receiving care in a specialized trauma program. We compared the rate of VH within our sample using two different measures: 1) the auditory hallucination (AH) item in the Structured Clinical Interview for DSM-IV-TR (SCID), and 2) the thirteen questions involving VH in the Multidimensional Inventory of Dissociation (MID), a self-report questionnaire that comprehensively assesses pathological dissociation. We found that 45.7% of our sample met threshold for SCID AH, while 91.4% met criteria for MID VH. Receiver operating characteristics (ROC) analyses showed that while SCID AH and MID VH items have greater than chance agreement, the strength of agreement is only moderate, suggesting that SCID and MID VH items measure related but not identical constructs. Thirty-two patients met criteria for both SCID AH and at least one MID VH item ("unequivocal VH"), 32 for at least one MID VH item but not SCID AH ("ambiguous VH"), and 6 met criteria for neither ("unequivocal non-VH"). Relative to the ambiguous VH group, the unequivocal VH group had higher dissociation scores for child voices, and higher mean frequencies for child voices and Schneiderian voices. Our findings suggest that VH in women with TSD related to childhood abuse is common, but that the rate of VH depends on how the question is asked. We review prior studies examining AH and/or VH in TSD, focusing on the measures used to ascertain these experiences, and conclude that our two estimates are consistent with previous studies that used comparable instruments and patient samples. Our results add to growing evidence that VH-an experience typically considered psychotic or psychotic-like-is not equivalent to having a psychotic disorder. Instruments that assess VH apart from psychotic disorders and that capture their multidimensional nature may improve identification of VH, especially among patients with non-psychotic disorders.

Visual hallucinations associated with multimodal hallucinations, suicide attempts and morbidity of illness in psychotic disorders

BACKGROUND

Visual hallucinations (VH) are a common, but understudied symptom of psychosis, experienced by individuals across diagnostic categories of psychotic and neuropsychiatric conditions. There are limited data on VH and associated clinical phenotypes in adult idiopathic psychotic disorders, which are needed to elucidate their relevance to psychotic illness paradigms.

METHOD

In this cross-sectional study, we examined clinical risk factors for VH in a well-characterized sample of 766 patients with adult psychotic disorders across diagnostic categories of schizophrenia (n = 227), schizoaffective disorder (n = 210), and bipolar I disorder (n = 329). The Structured Clinical Interview for DSM-IV-TR was used for diagnosis and symptom measurements.

RESULTS

The prevalence of VH was 26.1% (200/766). Multivariate logistic regression showed that VH were independently associated with the presence of hallucinations in other modalities, including auditory, tactile, olfactory, and gustatory hallucinations. History of a suicide attempt and catatonic behavior were also associated with VH. In addition, specific delusions were associated with VH, in particular, delusions of control, and religious, erotomanic and jealousy delusions. Diagnosis, negative symptoms, and family history of psychosis were not independent predictors of VH.

CONCLUSIONS

Results showed the clinical and disease relevance of VH as they were associated with severe morbidity of illness, including suicide attempts and catatonic behavior. Findings also suggest a phenotype associated with hallucinations in other modalities and specific types of delusions. Based on our findings, VH may be a significant factor in assessing for suicidality and illness severity, warranting clinical attention and further study of underlying mechanisms.

Positive and general psychopathology associated with specific gray matter reductions in inferior temporal regions in patients with schizophrenia

Schizophrenia is a complex disorder that affects perception, cognition, and emotion causing symptoms such as delusions, hallucinations, and suspiciousness. Schizophrenia is also associated with structural cortical abnormalities including lower gray matter (GM) concentration, GM volume, and cortical thickness relative to healthy control individuals. However, the association between GM measures and symptom dimensions in schizophrenia is still not well understood. Here, we applied parallel independent component analysis (pICA), a higher-order statistical approach that identifies covarying patterns within two (or more) data modalities simultaneously, to link covarying brain networks of GM concentration with covarying linear combinations of the positive and negative syndrome scale (PANSS). In a large sample of patients with schizophrenia (n = 337) the association between these two data modalities was investigated. The pICA revealed a distinct PANSS profile characterized by increased delusional symptoms, suspiciousness, hallucinations, and anxiety, that was associated with a pattern of lower GM concentration in inferior temporal gyri and fusiform gyri and higher GM concentration in the sensorimotor cortex. GM alterations replicate previous findings; additionally, applying a multivariate technique, we were able to map a very specific symptom profile onto these GM alterations extending our understanding of cortical abnormalities associated with schizophrenia. Techniques like parallel ICA can reveal linked patterns of alterations across different data modalities that can help to identify biologically-informed phenotypes which might help to improve future treatment targets.

Characterizing the experience of auditory verbal hallucinations and accompanying delusions in individuals with a diagnosis of bipolar disorder: A systematic review

OBJECTIVES

The aim of the current study was to inform ongoing attempts to identify clinically meaningful subcategories of auditory verbal hallucination (AVH), and to evaluate evidence that might pertain to the suitability of current psychological interventions for people with bipolar disorder (BD) who experience psychotic symptoms.

METHODS

A comprehensive synthesis of findings on the phenomenology of AVH and delusions in BD is included, alongside a critical review of clinical and cognitive correlates. Studies published in the previous 20 years, until December 2016, were retrieved from the following databases: Embase, CINAHL, MEDLINE, PsycINFO and Web of Science. Thirty-two articles were reviewed after applying a set of predetermined inclusion criteria.

RESULTS

Psychotic symptoms were common in both manic and depressive phases, although higher frequencies were indicated in mania. Few detailed characterizations of AVH phenomenology were identified. Delusions with persecutory, grandiose and referential themes were the most common in BD. AVHs were associated with delusions and there was evidence to suggest that delusion subtype may vary according to mood state and type of AVH. Data on clinical correlates of AVH in BD were sparse. However, the results indicated that cognitive appraisals or interpretations of voices might be different in BD from those established to be predictive of clinical outcomes in schizophrenia spectrum disorders.

CONCLUSIONS

Clear gaps exist in our current understanding of the first-person experience of AVH in BD and the potential relationship to co-occurring symptoms, including delusions. Further research into cognitive interpretations of AVH in BD might inform adapted psychological interventions for psychotic symptoms in this population.

Barriers to disseminating brief CBT for voices from a lived experience and clinician perspective

Access to psychological therapies continues to be poor for people experiencing psychosis. To address this problem, researchers are developing brief interventions that address the specific symptoms associated with psychosis, i.e., hearing voices. As part of the development work for a brief Cognitive Behaviour Therapy (CBT) intervention for voices we collected qualitative data from people who hear voices (study 1) and clinicians (study 2) on the potential barriers and facilitators to implementation and engagement. Thematic analysis of the responses from both groups revealed a number of anticipated barriers to implementation and engagement. Both groups believed the presenting problem (voices and psychosis symptoms) may impede engagement. Furthermore clinicians identified a lack of resources to be a barrier to implementation. The only facilitator to engagement was reported by people who hear voices who believed a compassionate, experienced and trustworthy therapist would promote engagement. The results are discussed in relation to how these barriers could be addressed in the context of a brief intervention using CBT techniques.

Deconstructing Bipolar Disorder and Schizophrenia: A cross-diagnostic cluster analysis of cognitive phenotypes

BACKGROUND

Bipolar disorder (BD) and schizophrenia (SZ) show substantial overlap. It has been suggested that a subgroup of patients might contribute to these overlapping features. This study employed a cross-diagnostic cluster analysis to identify subgroups of individuals with shared cognitive phenotypes.

METHOD

143 participants (68 BD patients, 39 SZ patients and 36 healthy controls) completed a battery of EEG and performance assessments on perception, nonsocial cognition and social cognition. A K-means cluster analysis was conducted with all participants across diagnostic groups. Clinical symptoms, functional capacity, and functional outcome were assessed in patients.

RESULTS

A two-cluster solution across 3 groups was the most stable. One cluster including 44 BD patients, 31 controls and 5 SZ patients showed better cognition (High cluster) than the other cluster with 24 BD patients, 35 SZ patients and 5 controls (Low cluster). BD patients in the High cluster performed better than BD patients in the Low cluster across cognitive domains. Within each cluster, participants with different clinical diagnoses showed different profiles across cognitive domains.

LIMITATIONS

All patients are in the chronic phase and out of mood episode at the time of assessment and most of the assessment were behavioral measures.

CONCLUSIONS

This study identified two clusters with shared cognitive phenotype profiles that were not proxies for clinical diagnoses. The finding of better social cognitive performance of BD patients than SZ patients in the Lowe cluster suggest that relatively preserved social cognition may be important to identify disease process distinct to each disorder.

Hallucinations: A Systematic Review of Points of Similarity and Difference Across Diagnostic Classes

Hallucinations constitute one of the 5 symptom domains of psychotic disorders in DSM-5, suggesting diagnostic significance for that group of disorders. Although specific featural properties of hallucinations (negative voices, talking in the third person, and location in external space) are no longer highlighted in DSM, there is likely a residual assumption that hallucinations in schizophrenia can be identified based on these candidate features. We investigated whether certain featural properties of hallucinations are specifically indicative of schizophrenia by conducting a systematic review of studies showing direct comparisons of the featural and clinical characteristics of (auditory and visual) hallucinations among 2 or more population groups (one of which included schizophrenia). A total of 43 articles were reviewed, which included hallucinations in 4 major groups (nonclinical groups, drug- and alcohol-related conditions, medical and neurological conditions, and psychiatric disorders). The results showed that no single hallucination feature or characteristic uniquely indicated a diagnosis of schizophrenia, with the sole exception of an age of onset in late adolescence. Among the 21 features of hallucinations in schizophrenia considered here, 95% were shared with other psychiatric disorders, 85% with medical/neurological conditions, 66% with drugs and alcohol conditions, and 52% with the nonclinical groups. Additional differences rendered the nonclinical groups somewhat distinctive from clinical disorders. Overall, when considering hallucinations, it is inadvisable to give weight to the presence of any featural properties alone in making a schizophrenia diagnosis. It is more important to focus instead on the co-occurrence of other symptoms and the value of hallucinations as an indicator of vulnerability.

Auditory Cortex Characteristics in Schizophrenia: Associations With Auditory Hallucinations

BACKGROUND

Neuroimaging studies have demonstrated associations between smaller auditory cortex volume and auditory hallucinations (AH) in schizophrenia. Reduced cortical volume can result from a reduction of either cortical thickness or cortical surface area, which may reflect different neuropathology. We investigate for the first time how thickness and surface area of the auditory cortex relate to AH in a large sample of schizophrenia spectrum patients.

METHODS

Schizophrenia spectrum (n = 194) patients underwent magnetic resonance imaging. Mean cortical thickness and surface area in auditory cortex regions (Heschl's gyrus [HG], planum temporale [PT], and superior temporal gyrus [STG]) were compared between patients with (AH+, n = 145) and without (AH-, n = 49) a lifetime history of AH and 279 healthy controls.

RESULTS

AH+ patients showed significantly thinner cortex in the left HG compared to AH- patients (d = 0.43, P = .0096). There were no significant differences between AH+ and AH- patients in cortical thickness in the PT or STG, or in auditory cortex surface area in any of the regions investigated. Group differences in cortical thickness in the left HG was not affected by duration of illness or current antipsychotic medication.

CONCLUSIONS

AH in schizophrenia patients were related to thinner cortex, but not smaller surface area of the left HG, a region which includes the primary auditory cortex. The results support that structural abnormalities of the auditory cortex underlie AH in schizophrenia.

Auditory verbal hallucinations (AVHs) and related psychotic phenomena in mood disorders: analysis of the 2010 Survey of High Impact Psychosis (SHIP) data

BACKGROUND

Auditory verbal hallucinations (AVHs) are known to occur in mood disorders, but there has been scant research in the area. This paper aimed to explore the presence of hallucinations, and AVHs in particular, across affective disorders (with non-affective disorders serving as clinical reference groups). Specific attention was given to i) running commentary, ii) voices conversing, and iii) negative voices. A secondary aim was to examine patterns of associated delusional themes.

METHOD

Participants were 1550 Australians, aged 18-64 years, assigned to one of four groups on the basis of diagnosis: i) bipolar disorder (BD), ii) depressive psychosis (DP), iii) schizophrenia (SCZ), and iv) schizoaffective disorder (SAD). Relevant data collected from the 2010 Australian Survey of High Impact Psychosis (SHIP) was analysed.

RESULTS

Current prevalence of hallucinations was such that BD<DP; severity of hallucinations, and AVHs in particular, was in the order BD=DP<SAD=SCZ. These results were statistically significant. Negative voices, and concomitantly, persecutory delusions, were prominent across all clinical groups.

DISCUSSION

Future research should examine age of AVH onset as well as other forms of AVHs, whilst taking into account participants' specific mood states.

Identification of Distinct Psychosis Biotypes Using Brain-Based Biomarkers

OBJECTIVE

Clinical phenomenology remains the primary means for classifying psychoses despite considerable evidence that this method incompletely captures biologically meaningful differentiations. Rather than relying on clinical diagnoses as the gold standard, this project drew on neurobiological heterogeneity among psychosis cases to delineate subgroups independent of their phenomenological manifestations.

METHOD

A large biomarker panel (neuropsychological, stop signal, saccadic control, and auditory stimulation paradigms) characterizing diverse aspects of brain function was collected on individuals with schizophrenia, schizoaffective disorder, and bipolar disorder with psychosis (N=711), their first-degree relatives (N=883), and demographically comparable healthy subjects (N=278). Biomarker variance across paradigms was exploited to create nine integrated variables that were used to capture neurobiological variance among the psychosis cases. Data on external validating measures (social functioning, structural magnetic resonance imaging, family biomarkers, and clinical information) were collected.

RESULTS

Multivariate taxometric analyses identified three neurobiologically distinct psychosis biotypes that did not respect clinical diagnosis boundaries. The same analysis procedure using clinical DSM diagnoses as the criteria was best described by a single severity continuum (schizophrenia worse than schizoaffective disorder worse than bipolar psychosis); this was not the case for biotypes. The external validating measures supported the distinctiveness of these subgroups compared with clinical diagnosis, highlighting a possible advantage of neurobiological versus clinical categorization schemes for differentiating psychotic disorders.

CONCLUSIONS

These data illustrate how multiple pathways may lead to clinically similar psychosis manifestations, and they provide explanations for the marked heterogeneity observed across laboratories on the same biomarker variables when DSM diagnoses are used as the gold standard.

Auditory processing deficits in bipolar disorder with and without a history of psychotic features

OBJECTIVES

Auditory perception deficits have been identified in schizophrenia (SZ) and linked to dysfunction in the auditory cortex. Given that psychotic symptoms, including auditory hallucinations, are also seen in bipolar disorder (BD), it may be that individuals with BD who also exhibit psychotic symptoms demonstrate a similar impairment in auditory perception.

METHODS

Fifty individuals with SZ, 30 individuals with bipolar I disorder with a history of psychosis (BD+), 28 individuals with bipolar I disorder with no history of psychotic features (BD-), and 29 normal controls (NC) were administered a tone discrimination task and an emotion recognition task.

RESULTS

Mixed-model analyses of covariance with planned comparisons indicated that individuals with BD+ performed at a level that was intermediate between those with BD- and those with SZ on the more difficult condition of the tone discrimination task and on the auditory condition of the emotion recognition task. There were no differences between the BD+ and BD- groups on the visual or auditory-visual affect recognition conditions. Regression analyses indicated that performance on the tone discrimination task predicted performance on all conditions of the emotion recognition task. Auditory hallucinations in BD+ were not related to performance on either task.

CONCLUSIONS

Our findings suggested that, although deficits in frequency discrimination and emotion recognition are more severe in SZ, these impairments extend to BD+. Although our results did not support the idea that auditory hallucinations may be related to these deficits, they indicated that basic auditory deficits may be a marker for psychosis, regardless of SZ or BD diagnosis.

Auditory verbal hallucinations in bipolar disorder (BD) and major depressive disorder (MDD): A systematic review

BACKGROUND

Auditory verbal hallucinations (AVHs) are not uncommon in bipolar disorder (BD) and major depressive disorder (MDD), but there has been scant research in the area. The current paper aims to draw together and provide a critical overview of existing studies of AVHs in BD and MDD.

METHODS

A systematic review was undertaken using the search terms 'hallucinations' or 'hearing voices' in conjunction with 'bipolar disorder', 'mania' or 'manic-depressive' or 'major depressive disorder' or 'depression' or 'affective disorder' or 'mood disorder'. After applying a pre-defined set of inclusion criteria, 14 eligible peer-reviewed publications were accepted for further analysis.

RESULTS

Prevalence rates of AVHs in BD (11.3-62.8%) and MDD (5.4-40.6%) varied. When psychotic features were examined, persecutory and grandiose delusions were especially common in BD (though the latter did not necessarily occur in conjunction with AVHs). A single known neuroimaging study has suggested increased fronto-temporal connectivity relating to AVHs in BD.

LIMITATIONS

Methodological challenges relating to fluctuations in mood states and limited use of validated instruments, coupled with post-episode recall bias, pose as specific barriers to the collection of meaningful phenomenological information.

CONCLUSIONS

AVHs remains a central but largely understudied symptom in BD and MDD. Future research examining its phenomenology and clinical/neural correlates could bring about positive clinical implications as well as adapted therapeutic applications.

Hallucinations and inhibitory functioning in healthy young adults with high and low levels of hypomanic personality traits

INTRODUCTION

Hallucinations in schizophrenia and hallucination proneness in healthy young adults are associated with a common cognitive mechanism, namely impaired inhibitory control. Hallucinatory-like experiences also seem related to hypomanic symptoms in non-clinical participants; however, the mechanisms involved are unknown. We sought to examine self-reported hallucinatory/anomalous perceptual experiences in students selected for high versus low levels of hypomanic personality traits, and whether hypomania is characterised by deficient inhibitory control.

METHOD

Undergraduate students with either high (n = 26) or low (n = 28) scores on the Hypomanic Personality Scale-Revised (HPS-20) were compared on: (1) the Launay Slade Hallucination Scale-Revised (LSHS-R), a measure of hallucination proneness, (2) the Cardiff Anomalous Perceptions Scale (CAPS) and (3) the Inhibition of Currently Irrelevant Memories (ICIM) task, an index of intentional inhibition.

RESULTS

The high HPS group had higher total scores, as well as higher frequency (on CAPS only), intrusiveness and distress (CAPS) scores compared to the low HPS group. They also produced significantly more false alarms on the second run of the ICIM task than the low hypomania traits group.

CONCLUSIONS

Frequent, intrusive and distressing perceptual anomalies and proneness to hallucinations tend to occur in healthy individuals with hypomanic personality traits and may be associated with transient difficulties with inhibitory control. Inhibitory control may be a cognitive marker of vulnerability to hallucinations across diagnostic boundaries.

A Neuropsychological Approach to Auditory Verbal Hallucinations and Thought Insertion - Grounded in Normal Voice Perception

A neuropsychological perspective on auditory verbal hallucinations (AVH) links key phenomenological features of the experience, such as voice location and identity, to functionally separable pathways in normal human audition. Although this auditory processing stream (APS) framework has proven valuable for integrating research on phenomenology with cognitive and neural accounts of hallucinatory experiences, it has not yet been applied to other symptoms presumed to be closely related to AVH – such as thought insertion (TI). In this paper, I propose that an APS framework offers a useful way of thinking about the experience of TI as well as AVH, providing a common conceptual framework for both. I argue that previous self-monitoring theories struggle to account for both the differences and similarities in the characteristic features of AVH and TI, which can be readily accommodated within an APS framework. Furthermore, the APS framework can be integrated with predictive processing accounts of psychotic symptoms; makes predictions about potential sites of prediction error signals; and may offer a template for understanding a range of other symptoms beyond AVH and TI.

A synthesis of evidence on inhibitory control and auditory hallucinations based on the Research Domain Criteria (RDoC) framework

The National Institute of Mental Health initiative called the Research Domain Criteria (RDoC) project aims to provide a new approach to understanding mental illness grounded in the fundamental domains of human behavior and psychological functioning. To this end the RDoC framework encourages researchers and clinicians to think outside the [diagnostic] box, by studying symptoms, behaviors or biomarkers that cut across traditional mental illness categories. In this article we examine and discuss how the RDoC framework can improve our understanding of psychopathology by zeroing in on hallucinations- now widely recognized as a symptom that occurs in a range of clinical and non-clinical groups. We focus on a single domain of functioning-namely cognitive [inhibitory] control-and assimilate key findings structured around the basic RDoC "units of analysis," which span the range from observable behavior to molecular genetics. Our synthesis and critique of the literature provides a deeper understanding of the mechanisms involved in the emergence of auditory hallucinations, linked to the individual dynamics of inhibitory development before and after puberty; favors separate developmental trajectories for clinical and non-clinical hallucinations; yields new insights into co-occurring emotional and behavioral problems; and suggests some novel avenues for treatment.

Superior temporal metabolic changes related to auditory hallucinations: a (31)P-MR spectroscopy study in antipsychotic-free schizophrenia patients

Structural deficits in the superior temporal cortex and transverse temporal gyri appear to be related to auditory hallucinations in schizophrenia, which are a key symptom of this disorder. However, the cellular and neurochemical underpinnings are poorly understood and hardly studied in vivo. We used (31)P-MRS (magnetic resonance spectroscopy) with chemical shift imaging to assess the association between left superior temporal cortex metabolism and severity of auditory hallucinations in 29 schizophrenia patients off antipsychotics. Hallucinations scores derived from the Scale for the Assessment of Positive Symptoms showed significant positive correlations with both measures of phospholipids (phosphomonoesters and phosphodiesters), and energy (inorganic phosphate and phosphocreatine, but not adenosine tri-phosphate) metabolism in left superior temporal gyrus/Heschl gyrus voxels. There was no correlation of metabolites in these regions with formal thought disorder, a symptom also linked to superior temporal pathology, thus suggesting symptom specificity. Our findings provide a link between established structural deficits and neurochemical pathology related to membrane pathology and markers of general metabolic turnover.

The special treatment of first rank auditory hallucinations and bizarre delusions in the diagnosis of schizophrenia

The presence of a single first-rank auditory hallucination (FRAH) or bizarre delusion (BD) is sufficient to satisfy the symptom criterion for a DSM-IV-TR diagnosis of schizophrenia. We queried two independent databases to investigate how prevalent FRAH and BD are in schizophrenia spectrum disorders and whether the diagnosis depends on them. FRAH was common in both datasets (42.2% and 55.2%) and BD was present in the majority of patients (62.5% and 69.7%). However, FRAH and BD rarely determined the diagnosis. In the first database, we found only seven cases among 325 patients (2.1%) and in the second database we found only one case among 201 patients (0.5%) who were diagnosed based on FRAH or BD alone. Among patients with FRAH, 96% had delusions, 14-42% had negative symptoms, 15-21% had disorganized or catatonic behavior, and 20-23% had disorganized speech. Among patients with BD, 88-99% had hallucinations, 17-49% had negative symptoms, 20-27% had disorganized or catatonic behavior, and 21-25% had disorganized speech. We conclude that FRAH and BD are common features of schizophrenia spectrum disorders, typically occur in the context of other psychotic symptoms, and very rarely constitute the sole symptom criterion for a DSM-IV-TR diagnosis of schizophrenia.