Command hallucinations and clinical characteristics of suicidality in patients with psychotic spectrum disorders

Exploring the Relationship Between Suicidality and Persistent Negative Symptoms Following a First Episode of Psychosis

BACKGROUND AND HYPOTHESIS

Suicide is a leading cause of death in first-episode psychosis (FEP), with an elevated risk during the first year following illness onset. The association between negative symptoms and suicidality remains contentious. Some studies suggest that negative symptoms may be associated with lower suicidality, while others fail to find an association between the two. No previous studies have specifically investigated suicidality in Persistent Negative Symptoms (PNS) and its associated subgroups.

STUDY DESIGN

In a large cohort of FEP patients (n = 515) from an early intervention service, we investigated suicidality in those with PNS, secondary PNS (ie, sPNS; PNS with clinical-level positive, depressive, or extrapyramidal symptoms), and non-PNS (all other patients) over 24 months. Patients were categorized into PNS groups based on symptoms from month 6 to month 12, and suicidality was evaluated using the Brief Psychiatric Rating Scale (BPRS).

STUDY RESULTS

Covarying for age and sex, we found that sPNS had higher suicidality relative to PNS and non-PNS throughout the 24-month period, but PNS and non-PNS did not differ. These differences were maintained after adjusting for depressive symptoms.

CONCLUSION

We observed that PNS did not significantly differ from non-PNS. However, we identified sPNS as a group with elevated suicidality above and beyond depression, suggesting that sPNS would benefit from targeted intervention and that PNS categorization identifies a subgroup for whom negative symptoms are not associated with lower suicidality.

Suicidal behavior across a broad range of psychiatric disorders

Suicide is a leading cause of death worldwide. In 2020, some 12.2 million Americans seriously contemplated suicide, 3.2 million planned suicide attempts, and 1.2 million attempted suicide. Traditionally, the approach to treating suicidal behavior (SB) has been to treat the "underlying" psychiatric disorder. However, the number of diagnoses associated with SB is considerable. We could find no studies describing the range of disorders reported to be comorbid with SB. This narrative review summarizes literature documenting the occurrence of SB across the lifespan and the full range of psychiatric diagnoses, not only BPD and those that comprise MDE, It also describes the relevance of these observations to clinical practice, research, and nosology. The literature searches contained the terms "suicid*" and each individual psychiatric diagnosis and identified 587 studies. We did not include case reports, case series, studies only addressing suicidal ideation or non-suicidal self-injury (NSSI), studies on self-harm, not distinguishing between SB and NSSI and studies that did not include any individuals that met criteria for a specific DSM-5 diagnosis (n = 366). We found that SB (suicide and/or suicide attempt) was reported to be associated with 72 out of 145 diagnoses, although data quality varied. Thus, SB is not exclusively germane to Major Depressive Episode (MDE) and Borderline Personality Disorder (BPD), the only conditions for which it is a diagnostic criterion. That SB co-occurs with so many diagnoses reinforces the need to assess current and past SB regardless of diagnosis, and supports the addition of charting codes to the DSM-5 to indicate current or past SB. It also comports with new data that specific genes are associated with SB independent of psychiatric diagnoses, and suggests that SB should be managed with specific suicide prevention interventions in addition to treatments indicated for co-occurring diagnoses. SB diagnostic codes would help researchers and clinicians document and measure SB's trajectory and response to treatment over time, and, ultimately, help develop secondary and tertiary prevention strategies. As a separate diagnosis, SB would preclude situations in which a potentially life-threatening behavior is not accounted for by a diagnosis, a problem that is particularly salient when no mental disorder is present, as is sometimes the case.

Exploring the nature and prevalence of targeted violence perpetrated by persons found not criminally responsible on account of mental disorder

Although mental illness has a demonstrated link with violence, the prevalence of targeted (planned and goal-directed) violence perpetrated by individuals with mental illness and its association with psychiatric symptoms is relatively unexplored. File information was compared for all 293 individuals found not criminally responsible due to mental illness in British Columbia between 2001 and 2005, of whom 19% had committed targeted violence. Most individuals with targeted offenses displayed at least one warning behavior before their offense (93%); all displayed delusions and approximately one third exhibited hallucinations. Compared to individuals who perpetrated non-targeted offenses, the individuals with targeted offenses displayed greater proportions of threats/criminal harassment, had female victims, displayed a psychotic disorder and/or personality disorder, and displayed delusions during the offense. This implies that severe psychiatric disorders do not preclude the perpetration of planned violence and suggests that exploring symptoms of mental illness that may be proximally indicative of targeted violence is important in preventing future acts.

Auditory Hallucinations, Depressive Symptoms, and Current Suicidal Ideation or Behavior Among Patients with Acute-episode Schizophrenia

Suicide risk and auditory hallucinations are common in schizophrenia, but less is known about its associations. This cross-sectional study aimed to determine whether the presence and severity of auditory hallucinations were associated with current suicidal ideation or behavior (CSIB) among patients with schizophrenia. We interviewed 299 individuals with schizophrenia and acute symptoms and reviewed their medical records. Measurement included the Psychotic Symptom Rating Scale (PSYRATS-AH), the Calgary Depression Scale for Schizophrenia (CDSS), and the Positive and Negative Syndrome Scale. Logistic regression and path analysis were used. The CSIB prevalence was higher among patients with current auditory hallucination than those without (19.5% vs. 8.6%, crude odds ratio = 2.58, p = .009). Lifetime auditory hallucination experience (adjusted odds ratio [AOR] = 3.81; 95% CI: 1.45-10.05) or current auditory hallucination experience (AOR = 3.22; 95% CI: 1.25-8.28) can elevate the likelihood of CSIB while controlling for depressive symptoms and lifetime suicide-attempt history. Among those with auditory hallucinations, the emotional score of the PSYRATS-AH was positively associated with the CDSS score and there was a small indirect effect of the CDSS score on the association between the emotional domain score and CSIB (bias-corrected 95% CI, 0.02-0.20). In conclusion, the presence of auditory hallucinations was strongly associated with CSIB, independent of depressive symptoms and lifetime suicide attempts. Suicide risk assessment should consider auditory hallucination experience and patients' appraisal of its emotional characteristics. Future cohort studies are necessary to provide more conclusive evidence for the mediating pathways between auditory hallucinations and CSIB.HIGHLIGHTSThe presence of auditory hallucinations was associated with current suicidality.Auditory hallucinations' emotional severity was related to depressive symptoms.The severity of auditory hallucination was not directly associated with suicidality.

Attributes of auditory hallucinations that are associated with self-harm: A prospective cohort study

There is a well-documented epidemiological association between auditory hallucinations and self-harm in the general population. However, there has been limited research examining specific characteristics of auditory hallucinations (e.g., type, source, or context of voices) as correlates of self-harm. We used prospective data from the Tokyo Teen Cohort to explore whether characteristics of voices reported at age 14 were differentially associated with self-harm behaviors at ages 14 and 16. Among respondents with auditory hallucinations, respondents who experienced voices that "said something bad" about them or commented on their thoughts and actions were most likely to report concurrent self-harm, whereas positive or praising voices were protective. Negative voices continued to predict self-harm two years later, at age 16, even with adjustment for self-harm at age 14. The age of the voices, source of the voices, and context (e.g., falling asleep or while sick) was not associated with likelihood of reporting concurrent or subsequent self-harm behaviors. Assessing for negative voices in particular, rather than auditory hallucinations or psychotic experiences more broadly, may provide a more specific indicator of risk for self-harm among adolescents. The real-world utility of these epidemiological findings should be further examined in clinical settings.

Crisis service utilization following completion of a suicide safety plan for Veterans with and without affective and nonaffective psychosis

OBJECTIVE

Psychosis is associated with increased suicide risk. Safety planning is a suicide prevention practice that is associated with decreased suicidal behavior and psychiatric hospitalizations. A common feature of safety planning is listing of crisis line numbers. The primary purpose of this study was to compare Veterans with and without psychosis who completed a safety plan in terms of their next year crisis service use, including Veterans Crisis Line (VCL) calls, and suicidal behavior.

METHODS

Data were drawn from the VA San Diego's electronic medical record system for (N = 1602) safety plans from 2018 to 2021. Clinical records of crisis services and suicide attempt/death were recorded for one year after the safety plan.

RESULTS

Following completion of a safety plan, Veterans with psychosis were more likely to have a next year psychiatric hospitalization (OR = 4.1), emergency department visit (OR = 2.3), and psychiatric emergency clinic visit (OR = 2.2) than those without psychosis. In contrast, there were no group differences in likelihood of calling the VCL.

CONCLUSIONS

Veterans with psychosis who recently completed a safety plan do not show elevated rates of VCL use that are commensurate with increases in crisis service use. Interventions for this high-risk group may focus on understanding the motivation and ability to call the VCL as ways to enhance safety planning.

The differential associations of positive and negative symptoms with suicidality

BACKGROUND

Suicide is one of the leading causes of death in people with schizophrenia. Identifying risk factors for suicide in schizophrenia is therefore an important clinical and research priority.

METHOD

A cross-sectional secondary analysis was conducted on the DNA Polymorphisms in Mental Illness Study (DPIM) data. Suicidality data was extracted, and the number of positive and negative symptoms were established for a total of 1494 participants. Logistic and negative binomial regression analyses were conducted to assess for associations between positive or negative symptoms and suicidal ideation, attempt, or number of attempts, whilst adjusting for potential confounders.

RESULTS

Negative symptoms were associated with a reduction in the risk of suicidal ideation (odds ratio [OR]: 0.83; 95 % CI: 0.75-0.91) and suicide attempt (OR: 0.79; 95 % CI: 0.71-0.88) after adjusting for age and sex. Positive symptoms were associated with an increased risk of suicidal ideation (OR: 1.06; 95 % CI: 1.03-1.09), suicide attempt (OR: 1.04; 95 % CI: 1.00-1.07) and number of suicide attempts (incidence rate ratio [IRR]: 1.05; 95 % CI: 1.01-1.08). Further adjusting for depressive symptoms slightly increased the magnitude of associations with negative symptoms but attenuated associations between positive symptoms and suicidality to the null.

CONCLUSIONS

Negative symptoms are associated with a reduced risk of suicidality, whilst positive symptoms are associated with an increased risk of suicidality. Depressive symptoms may confound or mediate these associations.

Differences between delusional disorder and schizophrenia: A mini narrative review

Psychotic syndromes are divided into affective and non-affective forms. Even among the non-affective forms, substantial differences exist. The aim of this relatively brief review is to synthesize what is known about the differences between two non-affective psychoses, schizophrenia and delusional disorder (DD), with respect to clinical, epidemiological, sociodemographic, and treatment response characteristics. A PubMed literature search revealed the following: in schizophrenia, hallucinations, negative symptoms and cognitive symptoms are prominent. They are rare in DD. Compared to schizophrenia patients, individuals with DD maintain relatively good function, and their delusions are believable; many are beliefs that are widely held in the general population. Treatments are generally similar in these two forms of psychosis, with the exception that antidepressants are used more frequently in DD and, for acute treatment, effective antipsychotic doses are lower in DD than in schizophrenia. It is with the hope that the contrasts between these two conditions will aid in the provision of safe and effective treatment for both that this review has been conducted.

Hospital-Based Suicides: Challenging Existing Myths

Myths are widely held and often based on false beliefs. To improve patient safety and speed the translation of research to clinical practice, we highlight and then debunk 10 common myths regarding the assessment, treatment, and management of hospitalized patients at risk for suicide. Myths regarding hospital-based suicides are examined and empirical evidence that counters each myth is offered. Ten common myths regarding hospital-based suicides are found to be untrue or unsupported based on existing empirical evidence. Rethinking common beliefs and practices that lack empirical support and seeking alternatives based on research evidence is consistent with an emphasis on evidence-based practices leading to improved patient care and protection.

Performance in Practice: Practice Assessment Tool for the Care of Patients With Schizophrenia

Schizophrenia is associated with significant health, social, occupational, and economic burdens, including increased mortality. Despite extensive and robust research on the treatment of individuals with schizophrenia, many individuals with the illness do not currently receive evidence-based pharmacological and nonpharmacological treatments. The American Psychiatric Association Practice Guideline for the Treatment of Patients With Schizophrenia, Third Edition, aims to enhance knowledge and increase the appropriate use of interventions for schizophrenia, thereby improving the quality of care and treatment outcomes. To this end, this evidence-based Performance in Practice tool can facilitate the implementation of a systematic approach to practice improvement for the care of individuals with schizophrenia. This practice assessment activity can also be used in partial fulfillment of Continuing Medical Education and Maintenance of Certification, part IV, requirements, which can also satisfy requirements for the Centers for Medicare & Medicaid Services Merit-based Incentive Payment System program.

Violence and Suicide Risk Assessment in Youth with Psychotic Disorders: Practical Considerations for Community Clinicians

Psychosis is a unique and significant risk factor associated with violent and suicidal behavior and warrants special consideration. This article presents a careful review of the literature on violence risk and psychosis and suicide risk and psychosis as it pertains to youth or those who have been newly diagnosed with or are at high risk for psychotic disorders. Each topic is covered in reference to general considerations and specific psychotic symptoms (eg, hallucinations, delusions, paranoia). The reader can refer to practical boxes to assist in identifying relevant risk factors and examples of questions to ask the patient and family.

Psychotic Symptoms Predict Suicidal Behavior Postdischarge in High Risk Psychiatric Inpatients

BACKGROUND

Psychotic disorders, as well as psychotic symptoms, are associated with a greater lifetime risk of suicidal behavior (SB). It is not known, however, whether psychotic symptoms are independent predictors for short-term SB.

METHODS

Data were collected from 201 psychiatric inpatients at Mount Sinai Beth Israel Hospital. Self-reported psychotic symptoms were assessed using the Brief Symptom Inventory (BSI). Postdischarge SB defined as an aborted, interrupted, or actual suicide attempt was assessed using the Columbia-Suicide Severity Rating Scale (C-SSRS), during the 4 to 8 weeks following discharge from an inpatient psychiatric unit (n=127, 63% retention). Logistic regressions were performed to assess the relationships between psychotic symptoms and SB, controlling for primary psychiatric disorders.

RESULTS

Self-reported psychotic symptoms were associated with subsequent postdischarge SB. There was no significant difference between the SB versus no SB groups on the basis of primary psychiatric disorder. Self-reported psychotic symptoms remained an independent and significant predictor of postdischarge SB when the analysis controlled for primary psychiatric disorder.

CONCLUSIONS

These results suggest that psychotic symptoms are a dimensional predictor of near-term postdischarge SB and are a necessary component of suicide risk assessment during inpatient hospitalization, independent of psychiatric diagnosis.

'Something wasn't quite right': a novel phenomenological analysis of internet discussion posts detailing initial awareness of psychosis

INTRODUCTION

A significant number of psychosis studies have focussed on and have attempted to model and frame the earliest psychosis experiences. Using a wide array of methodologies and targeting a variety of 'at risk' groups, researchers have offered much to inform our treatment responses, and understanding of psychosis onset and development.

OBJECTIVES

Due to the nature of scientific investigation however and investigator led exploration, those who experience psychosis are rarely afforded ultimate free rein to dictate and direct the exchange of information or to impose their unique narrative on that which is being explored. In an attempt to address this, the current study opportunistically harvested rich self-report data from replies to the question, "People that have been diagnosed with schizophrenia, what was the first time you noticed something wasn't quite right?" on the internet discussion forum Reddit.com.

METHODS

User data was analysed using Interpretive Phenomenological Analysis to identify key themes in participants' first experiences and initial awareness of psychosis.

RESULTS

While respondents varied widely in their recounted experiences and chose to describe these experiences in a variety of ways, analysis showed that (i) respondent distress was associated with psychosis onset timeframe, negative-voice auditory hallucinations, visual hallucinations, paranoid delusions, and insight (ii) early childhood psychosis experience resulted in novel explanatory schemas and psychosis/distress progression with contributory factors in adolescence and (iii) 41.3% of the sample reported self-realisation in gaining insight and greater insight was associated with help-seeking behaviour.

CONCLUSIONS

This novel use of publicly shared experiential data might enrich our existing qualitative literature concerning early psychosis.

Data-Driven Analysis of Functional Connectivity Reveals a Potential Auditory Verbal Hallucination Network

Schizophrenia is a severe global health problem, with over half of such patients experiencing auditory verbal hallucinations (AVHs). A better understanding of the neural correlates differentiating patients experiencing AVHs from patients not experiencing AVHs and healthy controls may identify targets that lead to better treatment strategies for AVHs. Employing 2 data-driven, voxel-based measure of functional connectivity, we studied 46 patients with schizophrenia or schizoaffective disorder (28 experiencing AVHs and 18 not experiencing AVHs). Twenty healthy controls matched for age, gender, ethnicity, education level, handedness, and estimated verbal intelligence were included for comparison. The intrinsic connectivity distribution (ICD) was used to model each voxel's connectivity to the rest of the brain using a Weibull distribution. To investigate lateralization of connectivity, we used cross-hemisphere ICD, a method that separates the contribution of each hemisphere to interrogate connectivity laterality. Patients with AVHs compared with patients without AVHs exhibited significantly decreased whole-brain connectivity in the medial prefrontal cortex and posterior cingulate cortex, less lateralized connectivity in left putamen, and more lateralized connectivity in left interior frontal gyrus. Correlations with Auditory Hallucination Rating Scale (AHRS) and post hoc seed connectivity analyses revealed significantly altered network connectivity. Using the results from all analyses comparing the patient groups and correlations with AHRS, we identified a potential AVH network, consisting of 25 nodes, showing substantial overlap with the default mode network and language processing networks. This network as a whole, instead of individual nodes, may represent actionable targets for interventions.

A biopsychosocial evaluation of the risk for suicide in schizophrenia

The risk of suicide is greatly increased in individuals with schizophrenia. Previous research has identified several potential risk factors for suicidal behavior in schizophrenia, although their ability to independently predict suicide is limited. The objective of this review was to systematically analyze and identify the interaction between the proposed risk factors in the literature that may predict suicidal behavior in schizophrenia. Articles that explored suicidal behavior and suicide risk in schizophrenia that were published between 1980 and August of 2015, indexed in PubMed, MEDLINE, and Scopus were systematically reviewed. Many studies proposed a range of biopsychosocial risk factors that may independently lead to suicide in schizophrenia. These risk factors appear to be mainly related to stress, a history of suicidal behavior, and psychotic symptoms. It is clear, however, that many of these factors do not act independently and in fact require the reciprocal interaction of several of them to pose a risk for suicide in schizophrenia. Independently, the power of many risk factors to predict suicide is limited. Future studies should continue to adopt a multidimensional approach by considering the interaction of several factors in assessing the risk for suicide in schizophrenia.

Psychosis as a risk factor for suicidal thoughts and behaviors: a meta-analysis of longitudinal studies

BACKGROUND

Research has long noted higher prevalence rates of suicidal thoughts and behaviors among individuals with psychotic symptoms. Major theories have proposed several explanations to account for this association. Given the differences in the literature regarding the operationalization of psychosis and sample characteristics, a quantitative review is needed to determine to what extent and how psychosis confers risk for suicidality.

METHODS

We searched PsycInfo, PubMed, and GoogleScholar for studies published before 1 January 2016. To be included in the analysis, studies must have used at least one psychosis-related factor to longitudinally predict suicide ideation, attempt, or death. The initial search yielded 2541 studies. Fifty studies were retained for analysis, yielding 128 statistical tests.

RESULTS

Suicide death was the most commonly studied outcome (43.0%), followed by attempt (39.1%) and ideation (18.0%). The median follow-up length was 7.5 years. Overall, psychosis significantly conferred risk across three outcomes, with weighted mean ORs of 1.70 (1.39-2.08) for ideation, 1.36 (1.25-1.48) for attempt, and 1.40 (1.14-1.72) for death. Detailed analyses indicated that positive symptoms consistently conferred risk across outcomes; negative symptoms were not significantly associated with ideation, and were protective against death. Some small moderator effects were detected for sample characteristics.

CONCLUSIONS

Psychosis is a significant risk factor for suicide ideation, attempt, and death. The finding that positive symptoms increased suicide risk and negative symptoms seemed to decrease risk sheds light on the potential mechanisms for the association between psychosis and suicidality. We note several limitations of the literature and offer suggestions for future directions.

Auditory Verbal Hallucinations in Borderline Personality Disorder and the Efficacy of Antipsychotics: A Systematic Review

Background: Auditory verbal hallucinations (AVH) are experienced more frequently by patients with borderline personality disorder (BPD) than previously assumed. However, consensus is lacking on how to treat them. Objective: To provide a systematic review of studies reporting on AVH in patients with BPD, with a focus on the efficacy of treatment of psychotic symptoms. Methods: For this review a systematic search was made in the PubMed and Ovid databases, and mean weighted prevalence rates, adjusted for sample size, were computed. Results: The search yielded 36 studies describing a total of 1,263 patients. Auditory hallucinations (including AVH) were reported in 27% of hospitalized BPD patients; AVH were reported in 25% of all patients and in 24% of outpatients. Of the hallucinating patients, 78% experienced AVH at least once per day, for a duration of several days to many years. On the whole, patients with BPD regarded their voices as malevolent and omnipotent in nature. Compared to patients with schizophrenia, the phenomenological characteristics of AVH were similar and the ensuing distress was equal or even higher, whereas scores for other positive symptoms were lower. The presence of AVH in BPD was associated with an increase of suicide plans and attempts, and more frequent hospitalization. Moreover, AVH in the context of BPD were associated with higher prevalence rates for post-traumatic stress disorder and emotional abuse. The efficacy of antipsychotics was investigated in 21 studies. Based on these studies, we conclude that both typical and atypical antipsychotics tend to have positive effects on AVH experienced in the context of BPD. The efficacy of cognitive-behavioral therapy and non-invasive brain stimulation has not yet been systematically assessed. Conclusions: These findings indicate that AVH experienced in the context of BPD are in need of proper diagnosis and treatment, and that antipsychotics tend to be beneficial in treating these (and other psychotic) symptoms.There is an urgent need for studies assessing the efficacy of cognitive-behavioral therapy and non-invasive brain stimulation in this underdiagnosed and undertreated group.

Suicidal Ideation in an Egyptian Sample of Hospitalized Patients with Acute Psychosis

BACKGROUND

Suicide mortality is 12 times higher in psychotic patients compared to the general population. Identifying characteristic of suicidal patients among this group might help in preventing such behavior.

AIMS

To assess the predictors of suicidal risk in patients hospitalized due to acute psychosis.

METHODS

One hundred and fifty patients (age 18 - 60 years) admitted with acute psychotic features were recruited. Patients were evaluated clinically by The Arabic version of Mini International Neuropsychiatric Interview (M.I.N.I.). Suicidal ideation was assessed using the Scale for Suicide Ideation (SSI).

RESULTS

Forty four out of 150 patients (29.33%) reported having current and/or previous history of suicidal ideation. Patients with major depression showed the highest suicidal tendencies followed by delusional disorder then bipolar disorder, psychosis related to substance abuse and schizophrenia. The more severe the psychotic symptoms, the more suicidal tendencies shown by patients. Predictors for suicidal ideations included diagnostic category, severity of psychotic features, unemployement and younger age CONCLUSION: Patients with psychosis that require admission to the hospital carry a high risk of suicidal ideation and behavior. Factors like unemployment, young age and psychiatric diagnosis and severity of psychosis could be predicting factors.

Differences between subjective experiences and observed behaviors in near-fatal suicide attempters with untreated schizophrenia: a qualitative pilot study

BACKGROUND

In cases of untreated schizophrenia, the patients' entourage often does not recognize the psychotic symptoms of the patient and the possibility that the patient may attempt suicide. The aim of this study was to investigate the discrepancies between the subjective experiences and observed behaviors in near-fatal suicide attempters with untreated schizophrenia.

METHODS

A semi-structured interview was carried out with seven near-fatal suicide attempters with untreated schizophrenia to examine the subjective experiences at the time of the suicide attempt. The families of the patients were also interviewed to determine their recognition of the patients' psychotic symptoms and the suicidal ideation. The interview data were analyzed qualitatively.

RESULTS

Six subjects were undergoing exacerbation of the psychotic symptoms at the time of exhibiting the suicide-related ideation. One subject had been in a prolonged depressive state before attempting suicide. Although all the patients experienced severe distress due to psychotic symptoms and depressive mood, they all exhibited only low level or no help-seeking behavior, and six of seven families had not recognized the change in the patient's mental condition.

CONCLUSIONS

Appropriate information about schizophrenia should be provided to the general public so that any help-seeking by the patients with this disease is not overlooked. In addition, accessible early intervention services for psychosis should be established.

Better than mermaids and stray dogs? Subtyping auditory verbal hallucinations and its implications for research and practice

The phenomenological diversity of auditory verbal hallucinations (AVH) is not currently accounted for by any model based around a single mechanism. This has led to the proposal that there may be distinct AVH subtypes, which each possess unique (as well as shared) underpinning mechanisms. This could have important implications both for research design and clinical interventions because different subtypes may be responsive to different types of treatment. This article explores how AVH subtypes may be identified at the levels of phenomenology, cognition, neurology, etiology, treatment response, diagnosis, and voice hearer's own interpretations. Five subtypes are proposed; hypervigilance, autobiographical memory (subdivided into dissociative and nondissociative), inner speech (subdivided into obsessional, own thought, and novel), epileptic and deafferentation. We suggest other facets of AVH, including negative content and form (eg, commands), may be best treated as dimensional constructs that vary across subtypes. After considering the limitations and challenges of AVH subtyping, we highlight future research directions, including the need for a subtype assessment tool.