Testing the hypothesis that psychotic illness begins when subthreshold hallucinations combine with delusional ideation

Emergence and Dynamics of Delusions and Hallucinations Across Stages in Early Psychosis

BACKGROUND

Hallucinations and delusions are often grouped together as positive symptoms of psychosis. However, recent evidence suggests that they may be driven by distinct computational and neural mechanisms. Examining the time course of their emergence may provide insights into the relationship between these underlying mechanisms.

METHODS

Participants from the second (N = 719) and third (N = 699) iterations of the North American Prodrome Longitudinal Study (NAPLS 2 and 3) were assessed for timing of clinical high risk for psychosis (CHR-P)-level delusion and hallucination onset. Pre-onset symptom patterns in patients with first-episode psychosis from the Prevention and Early Intervention Program for Psychosis (PEPP-Montréal) (N = 694) were also assessed. Symptom onset was determined at the baseline assessment, and the evolution of symptom patterns was examined over 24 months.

RESULTS

In all 3 samples, participants were more likely to report the onset of attenuated/subthreshold delusions prior to attenuated/subthreshold hallucinations (odds ratios [ORs]: NAPLS 2 = 4.09; NAPLS 3 = 4.14; PEPP, z = 7.01, p < .001) and to present with only attenuated/subthreshold delusions compared with only attenuated/subthreshold hallucinations (ORs: NAPLS 2 = 5.6; NAPLS 3 = 11.11; PEPP = 42.75). The reemergence of attenuated/subthreshold delusions after remission was also more common than reemergence of attenuated/subthreshold hallucinations (ps < .05), which more often resolved first (ps < .001). In both CHR-P samples, ratings of delusional ideation decreased with the onset of attenuated hallucinations (p = .007).

CONCLUSIONS

Attenuated/subthreshold delusions tend to emerge before attenuated/subthreshold hallucinations and may play a role in their development. Future work should examine the relationship between the mechanisms that drive these symptoms and its utility for diagnosis and treatment.

A Pilot Study of Adolescents with Psychotic Experiences: Potential Cerebellar Circuitry Disruption Early Along the Psychosis Spectrum

A berrant connectivity in the cerebellum has been found in psychotic conditions such as schizophrenia corresponding with cognitive and motor deficits found in these conditions. Diffusion differences in the superior cerebellar peduncles, the white matter connecting the cerebellar circuitry to the rest of the brain, have also been found in schizophrenia and high-risk states. However, white matter diffusivity in the peduncles in individuals with sub-threshold psychotic experiences (PEs) but not reaching the threshold for a definitive diagnosis remains unstudied. This study investigates the cerebellar peduncles in adolescents with PEs but no formal psychiatric diagnosis.Sixteen adolescents with PEs and 17 age-matched controls recruited from schools underwent High-Angular-Resolution-Diffusion neuroimaging. Following constrained spherical deconvolution whole-brain tractography, the superior, inferior and middle peduncles were isolated and virtually dissected out using ExploreDTI. Differences for macroscopic and microscopic tract metrics were calculated using one-way between-group analyses of covariance controlling for age, sex and estimated Total Intracranial Volume (eTIV). Multiple comparisons were corrected using Bonferroni correction.A decrease in fractional anisotropy was identified in the right (p = 0.045) and left (p = 0.058) superior cerebellar peduncle; however, this did not survive strict Bonferroni multiple comparison correction. There were no differences in volumes or other diffusion metrics in either the middle or inferior peduncles.Our trend level changes in the superior cerebellar peduncle in a non-clinical sample exhibiting psychotic experiences complement similar but more profound changes previously found in ultra-high-risk individuals and those with psychotic disorders. This suggests that superior cerebellar peduncle circuitry perturbations may occur early along in the psychosis spectrum.

Positive psychotic symptoms as a marker of clinical severity in a transdiagnostic sample of help-seeking adolescents

The present study aimed to examine the association between the presence, number, and type of positive psychotic symptoms (PPS) and clinical severity in adolescent patients. Five hundred-six patients aged 11-17 years were assigned to either the noPPS (n = 341), the delusional beliefs only (del; n = 32), the hallucinations only (hall; n = 80), or the delusional beliefs and hallucinations (del&hall; n = 53) group. Generalized Structural Equation Modeling was applied to identify the best-fitting model representing clinical severity indicated by psychiatric diagnoses, depressivity, personality pathology, non-suicidal self-injury, suicide attempts, perceived stress, and psychosocial impairments, assessed by interviews and questionnaires. The groups were compared concerning the final model's factors. The final model consisted of three factors representing psychopathology and functional impairments, self-harming behavior, and perceived stress (BIC difference to reference model: 103.99). Participants with any PPS scored higher on all factors than the noPPS group (differences in SD: 0.49-1.48). Additionally, the del&hall group scored 1.31 SD higher on psychopathology and functional impairments than the hall group, and 1.16 SD higher on self-harming behavior compared to the del group. Finally, the hall group scored 0.84 SD higher on self-harming behavior than the del group, with no group differences in the other factors. In adolescent patients, the presence of PPS may represent a marker for a more severe form of mental disorder, with hallucinations being indicative of self-harming behavior. Early transdiagnostic assessment of PPS seems indicated as it may inform treatment in the context of clinical staging.

Psychotic-like experiences predict the perceived intent to seek treatment: A network perspective

We aimed to investigate as to whether psychotic-like experiences (PLEs) predict the perceived intent to seek treatment. Our secondary aim was to explore which PLEs predict the perceived need to seek treatment using a network analysis. The study was based on a community sample of individuals with a negative history of psychiatric treatment. At baseline, they completed questionnaires recording the presence of PLEs, depressive, and anxiety symptoms. After 6-7 months, they were reassessed with respect to the perceived intent to seek treatment. A total of 1100 individuals were assessed at baseline (aged 27.1 ± 5.1 years, 48.6 % males). The follow-up assessment was completed by 581 individuals (52.8 %). Higher baseline levels of PLEs were associated with a greater intent to seek treatment at the follow-up before (Beta = 0.289, p < 0.001) and after adjustment for sociodemographic characteristics, depressive and anxiety symptoms (Beta = 0.128, p = 0.004). A network analysis demonstrated that the intent to seek treatment was connected to five nodes of PLEs including "déjà vu experiences" (weight = 0.046), "problems in differentiating reality and imagination" (weight = 0.103), "a lack of control over own ideas or thoughts" (weight = 0.077), "being distracted by distant sounds" (weight = 0.105), and "paranoid thoughts" (weight = 0.145). Findings from the present study indicate that PLEs might contribute to help-seeking behaviors regardless of co-occurring depressive and anxiety symptoms. However, specific PLEs may differ with respect to their effects on the perceived intent to seek treatment.

Brief rapport: Perceptual aberration in patients at ultra-high risk for psychosis

BACKGROUND

Ultra-high risk (UHR) is considered a forerunner of psychosis, but most UHR individuals do not later convert, yet remain symptomatic, disabled and help-seeking. Thus, there is an increased recognition of the UHR phenotype as a syndrome in itself, rather than merely a risk syndrome. It is therefore essential to investigate outcomes other than transition to psychosis. For this purpose, perceptual aberration appears to be a distinct, as well as a stable and less state-specific vulnerability indicator. We aimed to investigate perceptual aberration and associations with functional, neuro and social cognitive risk factors in an UHR sample.

METHOD

One hundred and twenty UHR and 64 healthy controls were compared on levels of perceptual aberration using the perceptual aberration scale. We further investigated cross-sectional associations between perceptual aberration and CAARMS (as a measure of subthreshold psychotic symptoms) and functional, neuro and social cognitive risk factors within the UHR using Spearmans ρ.

RESULTS

Perceptual aberration was significantly higher in UHR than in healthy controls and was associated with social functioning, executive functioning, and emotion recognition.

CONCLUSION

Our findings are consistent with a view of perceptual aberration as a stable vulnerability indicator that varies little with clinical state.

Evidence, and replication thereof, that molecular-genetic and environmental risks for psychosis impact through an affective pathway

BACKGROUND

There is evidence that environmental and genetic risk factors for schizophrenia spectrum disorders are transdiagnostic and mediated in part through a generic pathway of affective dysregulation.

METHODS

We analysed to what degree the impact of schizophrenia polygenic risk (PRS-SZ) and childhood adversity (CA) on psychosis outcomes was contingent on co-presence of affective dysregulation, defined as significant depressive symptoms, in (i) NEMESIS-2 (n = 6646), a representative general population sample, interviewed four times over nine years and (ii) EUGEI (n = 4068) a sample of patients with schizophrenia spectrum disorder, the siblings of these patients and controls.

RESULTS

The impact of PRS-SZ on psychosis showed significant dependence on co-presence of affective dysregulation in NEMESIS-2 [relative excess risk due to interaction (RERI): 1.01, p = 0.037] and in EUGEI (RERI = 3.39, p = 0.048). This was particularly evident for delusional ideation (NEMESIS-2: RERI = 1.74, p = 0.003; EUGEI: RERI = 4.16, p = 0.019) and not for hallucinatory experiences (NEMESIS-2: RERI = 0.65, p = 0.284; EUGEI: -0.37, p = 0.547). A similar and stronger pattern of results was evident for CA (RERI delusions and hallucinations: NEMESIS-2: 3.02, p < 0.001; EUGEI: 6.44, p < 0.001; RERI delusional ideation: NEMESIS-2: 3.79, p < 0.001; EUGEI: 5.43, p = 0.001; RERI hallucinatory experiences: NEMESIS-2: 2.46, p < 0.001; EUGEI: 0.54, p = 0.465).

CONCLUSIONS

The results, and internal replication, suggest that the effects of known genetic and non-genetic risk factors for psychosis are mediated in part through an affective pathway, from which early states of delusional meaning may arise.

Psychotic-Like Experiences in Adolescence Occurring in Combination or Isolation: Associations with Schizophrenia Risk Factors

Objectives

Individual adolescent psychotic‐like experiences (PLEs) are associated with schizophrenia risk factors. As DSM‐5 schizophrenia requires the co‐occurrence of at least two psychotic symptoms, we investigated whether co‐occurring adolescent PLEs have stronger associations with schizophrenia risk factors, lower quality of life and functioning, and have higher heritability, than individual PLEs.

Methods

Participants were 9646 16‐year‐old twins from the longitudinal Twins Early Development Study. We investigated co‐occurrence of high questionnaire scores for three PLE combinations: (1) paranoia and hallucinations; (2) paranoia or hallucinations, and cognitive disorganization; and (3) paranoia or hallucinations, and negative symptoms, and their associations with 11 schizophrenia‐relevant variables by regression analysis and structural equation twin modeling.

Results

Against expectation, none of the co‐occurring PLEs had the nominally strongest associations significantly more often than individual PLEs. Co‐occurring PLEs had the strongest associations with bullying victimization, cannabis use and lower life satisfaction, but individual PLEs had the strongest associations with cognitive function variables. Obstetric complications were most associated with negative symptoms. Secondary analysis revealed that co‐occurrence of cognitive disorganization and negative symptoms had the nominally strongest associations with most schizophrenia‐relevant variables overall and relatively high heritability (67%).

Conclusions

Focusing on co‐occurrence enhances some individual PLE associations but obscures others. The combination of subjective cognitive disorganization plus observed negative symptoms showed a broad range of enhanced associations with schizophrenia‐relevant variables. Future research could investigate associations with other risk factors and the ability of this PLE combination to predict onset of schizophrenia.

Focusing on co‐occurring psychotic‐like experiences (PLEs) in adolescence enhances some individual PLE associations but may obscure others

While victimization, cannabis use, and lower life satisfaction have broad associations with PLE combinations, cognitive variables are most associated with cognitive disorganization and negative symptoms, and obstetric complications are most associated with negative symptoms

The combination of subjective cognitive disorganization and observed negative symptoms has a relatively broad range of enhanced associations with schizophrenia‐relevant variables and relatively high heritability

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

What makes the psychosis 'clinical high risk' state risky: psychosis itself or the co-presence of a non-psychotic disorder?

AIMS

Although attenuated psychotic symptoms in the psychosis clinical high-risk state (CHR-P) almost always occur in the context of a non-psychotic disorder (NPD), NPD is considered an undesired 'comorbidity' epiphenomenon rather than an integral part of CHR-P itself. Prospective work, however, indicates that much more of the clinical psychosis incidence is attributable to prior mood and drug use disorders than to psychosis clinical high-risk states per se. In order to examine this conundrum, we analysed to what degree the 'risk' in CHR-P is indexed by co-present NPD rather than attenuated psychosis per se.

METHODS

We examined the incidence of early psychotic experiences (PE) with and without NPD (mood disorders, anxiety disorders, alcohol/drug use disorders), in a prospective general population cohort (n = 6123 at risk of incident PE at baseline). Four interview waves were conducted between 2007 and 2018 (NEMESIS-2). The incidence of PE, alone (PE-only) or with NPD (PE + NPD) was calculated, as were differential associations with schizophrenia polygenic risk score (PRS-Sz), environmental, demographical, clinical and cognitive factors.

RESULTS

The incidence of PE + NPD (0.37%) was lower than the incidence of PE-only (1.04%), representing around a third of the total yearly incidence of PE. Incident PE + NPD was, in comparison with PE-only, differentially characterised by poor functioning, environmental risks, PRS-Sz, positive family history, prescription of antipsychotic medication and (mental) health service use.

CONCLUSIONS

The risk in 'clinical high risk' states is mediated not by attenuated psychosis per se but specifically the combination of attenuated psychosis and NPD. CHR-P/APS research should be reconceptualised from a focus on attenuated psychotic symptoms with exclusion of non-psychotic DSM-disorders, as the 'pure' representation of a supposedly homotypic psychosis risk state, towards a focus on poor-outcome NPDs, characterised by a degree of psychosis admixture, on the pathway to psychotic disorder outcomes.

Validation of the Launay-Slade Hallucination Scale among Indian Healthy Adults

Psychotic Like Experiences (PLEs) have been reported in several cultures. The 16 item Launay-Slade Hallucination Scale-Extended (LSHS-E) measures hallucination like experiences (HLEs) in the general population. This study investigated the psychometric properties and the factor structure of LSHS-E Hindi among healthy adults of Delhi. LSHS-E was translated from English to Hindi and then back to English. It was administered as a paper pencil questionnaire to 182 adults from the general population. Reliability of LSHS-E Hindi was measured using Cronbach's alpha and factor structure was established using confirmatory factor analysis (CFA). It was tested against the Community Assessment of Psychic Experiences (CAPE-42) for convergent and divergent validity. Latent Class Analysis (LCA) was performed to identify subgroups with different endorsement of HLEs. Among 182, 18 participants reporting mental and neurological disorders were excluded. LSHS-E Hindi had good reliability (0.85; 95% CI: 0.82 to 0.88). CFA of Hindi LSHS-E revealed the a priori four-factor solution to be best, namely: 'intrusive thoughts', 'vivid daydreams', 'multisensory HLEs', 'auditory and visual HLEs'. LSHS-E Hindi showed stronger correlation with positive domain of CAPE than with negative and depression domains. LCA revealed three classes: low, intermediate and high endorsement of HLEs. Participants with highest endorsement of HLEs were less educated and had highest endorsement on all CAPE dimensions. LSHS-E Hindi has good psychometric properties and can be used to study HLEs in Indians. The four-factor structure model depicts the multidimensionality of HLEs, with 'intrusive thoughts' being the most commonly reported HLE in the sample. LCA supports the continuum hypothesis of HLEs.

Temporal dynamics of suspiciousness and hallucinations in clinical high risk and first episode psychosis

The objective of the current study is to elucidate the temporal dynamics of suspiciousness and hallucinations as they occur in daily life in the early stages of psychosis. Their prevalence and co-occurrence, as well as their temporal relation to affect and delusions, were compared between patients with a first psychotic episode (FEP) and individuals at clinical high risk for psychosis (CHRp). The Experience Sampling Method was used to investigate suspiciousness and hallucinatory experiences, delusions, and affect at semi-random moments throughout six days in 33 CHRp and 34 FEP. Overall, 91% of CHRp and 59% of FEP reported suspiciousness, and 24% and 39% reported hallucinations, respectively. Hallucinations almost always co-occurred with suspiciousness, whereas suspiciousness was often present without hallucinations. Suspicious episodes in CHRp occurred with marked increases in delusional intensity, while hallucinatory experiences were mostly absent. In FEP, a decrease of positive affect preceded suspicious episodes, while an increase of negative affect preceded hallucinatory episodes. Our results indicated the presence of a delusional mood (atmosphere) in CHRp as an experience in itself, without co-occurring or following hallucinations, thus refuting the anomalous experience hypothesis of psychosis. The co-occurrence of hallucinations, on the other hand, indicates a more severe stage of symptomatology.

Post-secondary students with symptoms of psychosis: A mixed-methods systematic review

Post-secondary students are at a heightened risk of psychosis, yet little is known about this population. The aim of this study was to conduct a mixed-methods systematic review of psychosis among post-secondary students, including student characteristics, overall prevalence, risk factors, interventions, and their reported experiences. Procedures were modelled on the Joanna Briggs Institute approach, while PRISMA guided conduct and reporting. A librarian created a systematic search of nine databases, and quality was assessed using JBI Critical Appraisal Tools. We pooled and analysed data according to objectives and recorded data using synthesis tables and narrative summaries. 26 articles published between 2006 and 2018 are included. The average age of participants was 21 years, and most identified as female and Caucasian. The prevalence of psychosis was often measured in a way that limited comparison across studies. Risk factors associated with symptoms of psychosis included substance use, depression, and younger age. Other risk factors trending towards a relationship included racial discrimination and anxiety. Protective factors included self-esteem and self-concept clarity. Five interventions were studied, with mixed results, and only three studies reported on the experience of students. While five promising interventions are identified, inadequate testing and replication limit confidence in their effectiveness and there is a notable deficit in qualitative evidence exploring the experiences of these students. Integrating knowledge on risk factors, interventions, and experiences of students with psychosis will help tailor and facilitate their health care while protecting their right to education.

Reduced hippocampal volume in adolescents with psychotic experiences: A longitudinal population-based study

AIMS

Smaller hippocampal volumes are among the most consistently reported neuroimaging findings in schizophrenia. However, little is known about hippocampal volumes in people who report psychotic experiences. This study investigated differences in hippocampal volume between young people without formal diagnoses who report psychotic experiences (PEs) and those who do not report such experiences. This study also investigated if any differences persisted over two years.

METHODS

A nested case-control study of 25 adolescents (mean age 13.5 years) with reported PEs and 25 matched controls (mean age 13.36 years) without PEs were drawn from a sample of 100 local schoolchildren. High-resolution T1-weighted anatomical imaging and subsequent automated cortical segmentation (Freesurfer 6.0) was undertaken to determine total hippocampal volumes. Comprehensive semi-structured clinical interviews were also performed including information on PEs, mental diagnoses and early life stress (bullying). Participants were invited for a second scan at two years.

RESULTS

19 adolescents with PEs and 19 controls completed both scans. Hippocampal volumes were bilaterally lower in the PE group compared to the controls with moderate effects sizes both at baseline [left hippocampus p = 0.024 d = 0.736, right hippocampus p = 0.018, d = 0.738] and at 2 year follow up [left hippocampus p = 0.027 d = 0.702, right = 0.048 d = 0.659] throughout. These differences survived adjustment for co-morbid mental disorders and early life stress.

CONCLUSIONS

Psychotic experiences are associated with total hippocampal volume loss in young people and this volume loss appears to be independent of possible confounders such as co-morbid disorders and early life stress.

Terminology and assessment tools of psychosis: A systematic narrative review

AIM

Phenomena within the psychosis continuum that varies in frequency/duration/intensity have been increasingly identified. Different terms describe these phenomena, however there is no standardization within the terminology. This review evaluated the definitions and assessment tools of seven terms - (i) 'psychotic experiences'; (ii) 'psychotic-like experiences'; (iii) 'psychotic-like symptoms'; (iv) 'attenuated psychotic symptoms'; (v) 'prodromal psychotic symptoms'; (vi) 'psychotic symptomatology'; and (vii) 'psychotic symptoms'.

METHODS

EMBASE, MEDLINE, and CINAHL were searched during February-March 2019. Inclusion criteria included 1989-2019, full text, human, and English. Papers with no explicit definition or assessment tool, duplicates, conference abstracts, systematic reviews, meta-analyses, or no access were excluded.

RESULTS

A total of 2238 papers were identified and of these, 627 were included. Definitions and assessment tools varied, but some trends were found. Psychotic experiences and psychotic-like experiences were transient and mild, found in the general population and those at-risk. Psychotic-like symptoms were subthreshold and among at-risk populations and non-psychotic mental disorders. Attenuated psychotic symptoms were subthreshold but associated with distress, risk, and help-seeking. Prodromal psychotic symptoms referred to the prodrome of psychotic disorders. Psychotic symptomatology included delusions and hallucinations within psychotic disorders. Psychotic symptoms was the broadest term, encompassing a range of populations but most commonly involving hallucinations, delusions, thought disorder, and disorganization.

DISCUSSION

A model for conceptualizing the required terms is proposed and future directions needed to advance this field of research are discussed.

Delusions in the general population: A systematic review with emphasis on methodology

The presence of delusions is considered a key feature of psychosis, but despite the psychopathological centrality of the concept of delusion, its definition and comprehension is a matter of continuing debate. In recent years studies showing that delusions are common in the general population have accumulated and challenged the way we perceive psychotic illness. In this systematic review, we examine the basis of the psychosis continuum-hypothesis, by reviewing a representative section of the original literature that report measures of delusional ideation in the general population, focusing specifically on methodology. Three online databases were systematically searched for relevant studies. After applying criteria of inclusion and exclusion, 17 articles were included for comprehensive review. Estimates of the distribution of delusions in the general population vary substantially, as does the mode of assessment. The methodology relies with few exceptions exclusively on self-report and fully structured interview by lay person. We conclude that measures of delusions in the general population should be interpreted cautiously due to inherent difficulties in methodology. Hypothesizing a continuum of delusion between normality and full-blown psychosis is deemed premature based on the reviewed studies.

DSM outcomes of psychotic experiences and associated risk factors: 6-year follow-up study in a community-based sample

BACKGROUND

Psychotic experiences (PEs) may predict a range of common, non-psychotic disorders as well as psychotic disorders. In this representative, general population-based cohort study, both psychotic and non-psychotic disorder outcomes of PE were analysed, as were potential moderators.

METHODS

Addresses were contacted in a multistage clustered probability sampling frame covering 11 districts and 302 neighbourhoods at baseline (n = 4011). Participants were interviewed with the Composite International Diagnostic Interview (CIDI) both at baseline and at 6-year follow-up. Participants with PE at baseline were clinically re-interviewed with the SCID-I at follow-up. The role of socio-demographics, characteristics of PE, co-occurrence of mood disorders and family history of mental disorders were tested in the association between baseline PE and follow-up diagnosis.

RESULTS

In the participants with baseline PE, the psychotic disorder diagnosis rate at follow up was 7.0% - much lower than the rates of DSM-IV mood disorders without psychotic features (42.8%) and other non-psychotic disorders (24.1%). Within the group with baseline PE, female sex, lower socio-economic status, co-occurrence of mood disorders, family history of a mental disorder and persistence of PE predicted any follow-up DSM diagnosis. Furthermore, onset of psychotic v. non-psychotic disorder was predicted by younger age (15-30 years), co-presence of delusional and hallucinatory PE and family history of severe mental illness.

CONCLUSION

The outcome of PE appears to be a consequence of baseline severity of multidimensional psychopathology and familial risk. It may be useful to consider PE as a risk indicator that has trans-diagnostic value.

White noise speech illusions in the general population: The association with psychosis expression and risk factors for psychosis

Introduction

Positive psychotic experiences are associated with increased rate of white noise speech illusions in patients and their relatives. However, findings have been conflicting to what degree speech illusions are associated with subclinical expression of psychosis in the general population. The aim of this study was to investigate the link between speech illusions and positive psychotic experiences in a general population sample. In addition, the hypothesis that speech illusions are on the pathway from known risk factors for psychosis (childhood adversity and recent life events) to subthreshold expression of psychosis, was examined.

Methods

In a follow-up design (baseline and 6 months) the association between the number of white noise speech illusions and self-reported psychotic experiences, assessed with the Community Assessment of Psychic Experiences (CAPE), was investigated in a general population sample (n = 112). In addition, associations between speech illusions and childhood adversity and life events, using the Childhood Experiences of Care and Abuse questionnaire and the Social Readjustment Rating Scale, were investigated.

Results

No association was found between the CAPE positive scale and the number of white noise speech illusions. The CAPE positive scale was significantly associated with childhood adversity between 12 and 16 years (B = 0.980 p = 0.001) and life events (B = 0.488 p = 0.044). The number of speech illusions showed no association with either life events or childhood adversity.

Conclusion

In the nonclinical population, the pathway from risk factors to expression of subclinical psychotic experiences does not involve white noise speech illusions as an intermediate outcome.

White Noise Speech Illusions: A Trait-Dependent Risk Marker for Psychotic Disorder?

Introduction: White noise speech illusions index liability for psychotic disorder in case-control comparisons. In the current study, we examined i) the rate of white noise speech illusions in siblings of patients with psychotic disorder and ii) to what degree this rate would be contingent on exposure to known environmental risk factors (childhood adversity and recent life events) and level of known endophenotypic dimensions of psychotic disorder [psychotic experiences assessed with the Community Assessment of Psychic Experiences (CAPE) scale and cognitive ability]. Methods: The white noise task was used as an experimental paradigm to elicit and measure speech illusions in 1,014 patients with psychotic disorders, 1,157 siblings, and 1,507 healthy participants. We examined associations between speech illusions and increasing familial risk (control -> sibling -> patient), modeled as both a linear and a categorical effect, and associations between speech illusions and level of childhood adversities and life events as well as with CAPE scores and cognitive ability scores. Results: While a positive association was found between white noise speech illusions across hypothesized increasing levels of familial risk (controls -> siblings -> patients) [odds ratio (OR) linear 1.11, 95% confidence interval (CI) 1.02-1.21, p = 0.019], there was no evidence for a categorical association with sibling status (OR 0.93, 95% CI 0.79-1.09, p = 0.360). The association between speech illusions and linear familial risk was greater if scores on the CAPE positive scale were higher (p interaction = 0.003; OR_{low CAPE positive scale} 0.96, 95% CI 0.85-1.07; OR_{high CAPE positive scale} 1.26, 95% CI 1.09-1.46); cognitive ability was lower (p interaction < 0.001; OR_{high cognitive ability} 0.94, 95% CI 0.84-1.05; OR_{low cognitive ability} 1.43, 95% CI 1.23-1.68); and exposure to childhood adversity was higher (p interaction < 0.001; OR_{low adversity} 0.92, 95% CI 0.82-1.04; OR_{high adversity} 1.31, 95% CI 1.13-1.52). A similar, although less marked, pattern was seen for categorical patient-control and sibling-control comparisons. Exposure to recent life events did not modify the association between white noise and familial risk (p interaction = 0.232). Conclusion: The association between white noise speech illusions and familial risk is contingent on additional evidence of endophenotypic expression and of exposure to childhood adversity. Therefore, speech illusions may represent a trait-dependent risk marker.

Measurement invariance of the Spanish Launay-Slade Hallucinations Scale-Extended version between putatively healthy controls and people diagnosed with a mental disorder

OBJECTIVES

The current study aimed at evaluating the reliability, convergent and divergent validity, and factor structure of the Spanish Launay-Slade Hallucinations Scale-Extended version (LSHS-E) in people with mental disorders and healthy controls.

METHODS

Four hundred and twenty-two individuals completed the Spanish LSHS-E and the Spanish Community Assessment of Psychic Experiences. The convergent and divergent validity of the LSHS-E was assessed with the three dimensions of the Community Assessment of Psychic Experiences (positive, negative, and depressive dimensions) in healthy controls and people with a mental disorder. Factor structure of the LSHS-E was assessed using confirmatory factor analysis and measurement invariance.

RESULTS

The LSHS-E had a good reliability in healthy controls and people with a mental disorder (Cronbach's = 0.83 and 0.91, respectively). The LSHS-E was more strongly associated with positive psychotic-like experiences than with depressive and negative symptoms. Four factors were found: (a) "intrusive thoughts"; (b) "vivid daydreams"; (c) "multisensory hallucination-like experiences"; and (d) "auditory-visual hallucination-like experiences" that were invariant between the group of healthy controls and people with a mental disorder.

CONCLUSION

The Spanish version of the LSHS-E possesses adequate psychometric properties, and the confirmatory factor analysis findings provide further support for the multidimensionality of proneness to hallucination in clinical and nonclinical samples.

Anomalous Perceptions and Beliefs Are Associated With Shifts Toward Different Types of Prior Knowledge in Perceptual Inference

Psychotic phenomena manifest in healthy and clinical populations as complex patterns of aberrant perceptions (hallucinations) and tenacious, irrational beliefs ( delusions). According to predictive processing accounts, hallucinations and delusions arise from atypicalities in the integration of prior knowledge with incoming sensory information. However, the computational details of these atypicalities and their specific phenomenological manifestations are not well characterized. We tested the hypothesis that hallucination-proneness arises from increased reliance on overly general application of prior knowledge in perceptual inference, generating percepts that readily capture the gist of the environment but inaccurately render its details. We separately probed the use of prior knowledge to perceive the gist vs the details of ambiguous images in a healthy population with varying degrees of hallucination- and delusion-proneness. We found that the use of prior knowledge varied with psychotic phenomena and their composition in terms of aberrant percepts vs aberrant beliefs. Consistent with previous findings, hallucination-proneness conferred an advantage using prior knowledge to perceive image gist but, contrary to predictions, did not confer disadvantage perceiving image details. Predominant hallucination-proneness actually conferred advantages perceiving both image gist and details, consistent with reliance on highly detailed perceptual knowledge. Delusion-proneness, and especially predominance of delusion-proneness over hallucination-proneness, conferred disadvantage perceiving image details but not image gist, though evidence of specific impairment of detail perception was preliminary. We suggest this is consistent with reliance on abstract, belief-like knowledge. We posit that phenomenological variability in psychotic experiences may be driven by variability in the type of knowledge observers rely upon to resolve perceptual ambiguity.

Evidence That Environmental and Familial Risks for Psychosis Additively Impact a Multidimensional Subthreshold Psychosis Syndrome

BACKGROUND

The observed link between positive psychotic experiences (PE) and psychosis spectrum disorder (PSD) may be stronger depending on concomitant presence of PE with other dimensions of psychopathology. We examined whether the effect of common risk factors for PSD on PE is additive and whether the impact of risk factors on the occurrence of PE depends on the co-occurrence of other symptom dimensions (affective dysregulation, negative symptoms, and cognitive alteration).

METHOD

Data from the Netherlands Mental Health Survey and Incidence Study 2 were used. Risk factors included childhood adversity, cannabis use, urbanicity, foreign born, hearing impairment, and family history of affective disorders. Logistic regression models were applied to test (1) the additive effect of risk factors (4 levels) on PE and (2) the moderating effects of symptom dimensions on the association between risk factors (present/absent) and PE, using additive interaction, expressed as the interaction contrast ratio.

RESULTS

Risk factors were additive: the greater the number of risk factors, the greater the odds of PE. Furthermore, concomitant presence of the other symptom dimensions all increased the impact of risk factors on PE. After controlling for age, sex, and education, only affective dysregulation and negative symptoms remained significant moderators; only affective dysregulation remained a significant moderator if all dimensions were adjusted for each other.

CONCLUSIONS

Risk factors may not be directly associated with PE but additively give rise to a multidimensional subthreshold state anticipating the multidimensional clinical syndrome. Early motivational and cognitive impairments in the context of PE may be reducible to affective dysregulation.

A systematic review and meta-analysis of mental health service use in people who report psychotic experiences

BACKGROUND

Self-reported psychotic experiences (PEs) are associated with psychopathology of all kinds, not just psychoses. However, systematic reviews on the relevance of this for health services are unavailable. Furthermore, whether association with service use is confounded by other psychopathology is unknown, and is relevant to prevention and treatment.

OBJECTIVES

Literature examining associations between PEs and service use was systematically reviewed. Study quality and the direction and extent of any associations were assessed, and meta-analysis conducted.

METHODS

Systematic review and meta-analysis was carried out as per PRISMA guidelines. A search of electronic databases was performed based on free-text and structured terms. Included studies were evaluated by two raters using a structured tool and estimates extracted for reporting.

RESULTS

Thirteen studies were returned. We found two prospective studies, and a minority of studies accounted for concurrent psychopathology, limiting our ability to test our main hypotheses. Five studies reported associations by different types of service use. Almost all studies assessed service use by self-report. Meta-analysis suggested that people who reported PEs were around twice as likely to report service use compared to those who did not (pooled OR for all included studies: 2.20,95% confidence intervals (95%CI): 1.66,2.91).

CONCLUSIONS

There was consistent evidence of association between PEs and mental health service use at the general population level. However, evidence for causation was poor due to a limited number of studies. Whether increased service use in this group is solely attributable to PEs, and therefore whether interventions aimed at limiting/preventing PEs might be effective, requires studies focusing on the relationships between PEs, psychopathology and service use.

The slow death of the concept of schizophrenia and the painful birth of the psychosis spectrum

The concept of schizophrenia only covers the 30% poor outcome fraction of a much broader multidimensional psychotic syndrome, yet paradoxically has become the dominant prism through which everything 'psychotic' is observed, even affective states with mild psychosis labelled 'ultra-high risk' (for schizophrenia). The inability of psychiatry to frame psychosis as multidimensional syndromal variation of largely unpredictable course and outcome - within and between individuals - hampers research and recovery-oriented practice. 'Psychosis' remains firmly associated with 'schizophrenia', as evidenced by a vigorous stream of high-impact but non-replicable attempts to 'reverse-engineer' the hypothesized biological disease entity, using case-control paradigms that cannot distinguish between risk for illness onset and risk for poor outcome. In this paper, the main issues surrounding the concept of schizophrenia are described. We tentatively conclude that with the advent of broad spectrum phenotypes covering autism and addiction in DSM5, the prospect for introducing a psychosis spectrum disorder - and modernizing psychiatry - appears to be within reach.

Psychotic experiences and incident suicidal ideation and behaviour: Disentangling the longitudinal associations from connected psychopathology

This study examines the longitudinal associations between psychotic experiences (PE) and incident suicidal ideation and behaviour in the general population, and to what degree the association may be confounded by non-psychotic psychopathology. Data from three prospective, general population cohorts were combined into one dataset (n=15,837) and analysed using logistic regression, controlling for continuous measures of depression, anxiety and mania symptoms. Analyses were conducted in the entire sample, and in subsamples stratified by presence or absence of mental disorders. The presence of PE at baseline increased the risk of incident suicidal ideation and behaviour. However, adjustment for dimensional measures of psychopathology reduced effect sizes, although PE remained significantly associated with suicide attempts. Further examination of the associations revealed that PE were only associated with suicide attempts in individuals with at least one mental disorder. Similarly, in individuals without mental disorders, the risk of suicidal ideation increased as PE co-occurred with more symptom domains. The results of this study confirm that individuals with PE are at increased risk of suicidal ideation and behaviour. However, these associations are not specific, but reflect the increased risk of suicidal ideation in individuals with subthreshold multidimensional psychopathology and suicide attempts in individuals with co-occurring mental disorders.

Introducing the White Noise task in childhood: associations between speech illusions and psychosis vulnerability

BACKGROUND

Auditory verbal hallucinations (AVH) are common during development and may arise due to dysregulation in top-down processing of sensory input. This study was designed to examine the frequency and correlates of speech illusions measured using the White Noise (WN) task in children from the general population. Associations between speech illusions and putative risk factors for psychotic disorder and negative affect were examined.

METHOD

A total of 1486 children aged 11-12 years of the Copenhagen Child Cohort 2000 were examined with the WN task. Psychotic experiences and negative affect were determined using the Kiddie-SADS-PL. Register data described family history of mental disorders. Exaggerated Theory of Mind functioning (hyper-ToM) was measured by the ToM Storybook Frederik.

RESULTS

A total of 145 (10%) children experienced speech illusions (hearing speech in the absence of speech stimuli), of which 102 (70%) experienced illusions perceived by the child as positive or negative (affectively salient). Experiencing hallucinations during the last month was associated with affectively salient speech illusions in the WN task [general cognitive ability: adjusted odds ratio (aOR) 2.01, 95% confidence interval (CI) 1.03-3.93]. Negative affect, both last month and lifetime, was also associated with affectively salient speech illusions (aOR 2.01, 95% CI 1.05-3.83 and aOR 1.79, 95% CI 1.11-2.89, respectively). Speech illusions were not associated with delusions, hyper-ToM or family history of mental disorders.

CONCLUSIONS

Speech illusions were elicited in typically developing children in a WN-test paradigm, and point to an affective pathway to AVH mediated by dysregulation in top-down processing of sensory input.

Exposure to environmental factors increases connectivity between symptom domains in the psychopathology network

BACKGROUND

We investigated to what degree environmental exposure (childhood trauma, urbanicity, cannabis use, and discrimination) impacts symptom connectivity using both continuous and categorical measures of psychopathology.

METHODS

Outcomes were continuous symptom dimensions of self-reported psychopathology using the Self-report Symptom Checklist-90-R in 3021 participants from The Early Developmental Stages of the Psychopathology (EDSP) study and binary DSM-III-R categories of mental disorders and a binary measure of psychotic symptoms in 7076 participants from The Netherlands Mental Health Survey and Incidence Study (NEMESIS-1). For each symptom dimension in the EDSP and mental disorder in the NEMESIS-1 as the dependent variable, regression analyses were carried out including each of the remaining symptom dimensions/mental disorders and its interaction with cumulative environmental risk load (the sum score of environmental exposures) as independent variables.

RESULTS

All symptom dimensions in the EDSP and related diagnostic categories in the NEMESIS-1 were strongly associated with each other, and environmental exposures increased the degree of symptom connectivity in the networks in both cohorts.

CONCLUSIONS

Our findings showing strong connectivity across symptom dimensions and related binary diagnostic constructs in two independent population cohorts provide further evidence for the conceptualization of psychopathology as a contextually sensitive network of mutually interacting symptoms.

Paranoid Ideation and Violence: Meta-analysis of Individual Subject Data of 7 Population Surveys

There is controversy whether associations between psychosis and violence are due to coexisting substance misuse and factors increasing risk in nonpsychotic persons. Recent studies in clinical samples have implicated independent effects of paranoid delusions. Research findings suggest that individual psychotic-like-experiences on the psychosis continuum in the general population are associated with violence; it remains unclear whether this association is due to psychiatric comorbidity. We pooled data from 7 UK general population surveys (n = 23 444) and conducted a meta-analysis of individual subject data. Further meta-analyses were performed to identify heterogeneity. Main exposure variables: 5 psychotic-like-experiences and a categorical measure of psychosis. Comorbidity was established through standardized self-report instruments. Information was collected on violence, severity, victims. Paranoid ideation was associated with violence (AOR 2.26, 95% CI 1.75-2.91), severity and frequency, even when controlling for effects of other psychotic-like-experiences. Associations were not explained by comorbid conditions, including substance dependence. Psychotic disorder was associated with violence and injury to the perpetrator but associations were explained by paranoid ideation. Individual associations between hypomania, thought insertion, hallucinations, and violence were nonsignificant after adjustments, and significantly associated only when comorbid with antisocial personality disorder. Strange experiences were only associated with intimate partner violence. Paranoid ideation on a psychosis-continuum in the general population was associated with violence. All other associations were explained by comorbidity. Further investigation should determine whether paranoid ideation among persons in the community require preventive interventions, similar to those presenting to mental health services. Nevertheless, risks are considerably increased for psychotic-like-experiences with co-occurring antisocial personality disorder.

Psychotic-Like Experiences and Psychological Distress: The Role of Resilience

BACKGROUND

The occurrence of psychotic-like experiences and schizotypal features in the general nonclinical population may imply a connection with psychosis-related liability.

OBJECTIVE

This study was designed to examine the role of resilience in the relationship of hallucination and delusion-like experiences and schizotypal features to psychological distress in a nonclinical sample.

DESIGN

The study sample (n = 432 university students) was selected through a stratified cluster sampling procedure, and measures of hallucination proneness, delusion proneness, schizotypal personality, and psychological distress were administered.

RESULTS

While all three indices of psychotic-like experiences correlated with one another, only hallucination proneness and schizotypal personality features correlated with psychological distress and only schizotypal traits correlated with resilience. Schizotypy was found to have an indirect effect on distress through resilience.

CONCLUSIONS

Findings imply the possibility of two types of schizotypy, with high or low resilience. It appears that schizotypes with low resilience may be susceptible to adversity and mental disorders, while high resilience may be protective.

Age of Onset and Lifetime Projected Risk of Psychotic Experiences: Cross-National Data From the World Mental Health Survey

BACKGROUND

Given the early age of onset (AOO) of psychotic disorders, it has been assumed that psychotic experiences (PEs) would have a similar early AOO. The aims of this study were to describe (a) the AOO distribution of PEs, (b) the projected lifetime risk of PEs, and (c) the associations of PE AOO with selected PE features.

METHODS

Data came from the WHO World Mental Health (WMH) surveys. A total of 31 261 adult respondents across 18 countries were assessed for lifetime prevalence of PE. Projected lifetime risk (at age 75 years) was estimated using a 2-part actuarial method. AOO distributions were described for the observed and projected estimates. We examined associations of AOO with PE type metric and annualized PE frequency.

RESULTS

Projected lifetime risk for PEs was 7.8% (SE = 0.3), slightly higher than lifetime prevalence (5.8%, SE = 0.2). The median (interquartile range; IQR) AOO based on projected lifetime estimates was 26 (17-41) years, indicating that PEs commence across a wide age range. The AOO distributions for PEs did not differ by sex. Early AOO was positively associated with number of PE types (F = 14.1, P < .001) but negatively associated with annualized PE frequency rates (F = 8.0, P < .001).

DISCUSSION

While most people with lifetime PEs have first onsets in adolescence or young adulthood, projected estimates indicate that nearly a quarter of first onsets occur after age 40 years. The extent to which late onset PEs are associated with (a) late onset mental disorders or (b) declining cognitive and/or sensory function need further research.

Psychosis as a transdiagnostic and extended phenotype in the general population

A large body of research indicates that weak expressions of positive psychotic symptoms ("psychotic experiences") can be measured in the general population, and likely represent the behavioural manifestation of distributed multifactorial (genetic and non-genetic) risk for psychosis. Psychotic experiences are a transdiagnostic phenomenon: the majority of individuals with these experiences have a diagnosis of non-psychotic disorder, particularly common mental disorder, in which psychotic experiences predict greater illness severity and poorer treatment response. Some of the people with common mental disorder and psychotic experiences will present to mental health services meeting criteria for "clinical high risk". Treatment of the transdiagnostic dimension of psychosis in individuals with common mental disorder who meet "clinical high risk" criteria thus may improve outcome (which cannot be interpreted as prevention of "schizophrenia"). Subthreshold psychotic experiences are transitory in about 80% of individuals, while around 20% go on to develop persistent psychotic experiences and 7% a psychotic disorder, with an annual transition rate of 0.5-1%. Persistence is associated, on the one hand, with environmental exposures, particularly childhood trauma, and, on the other, with network-type dynamic interactions between psychotic experiences themselves (e.g., interactions between hallucinatory experiences and delusional ideation) and between symptom dimensions (e.g., interactions between affective symptoms and psychotic experiences, or interactions between subthreshold negative symptoms and psychotic experiences). The study of psychotic experiences is helping to elucidate the mechanisms by which environmental and genetic influences shape the transdiagnostic expression of psychosis proneness, that is mostly transitory but may first become persistent over time and eventually give rise to transition to a psychotic disorder.

Religiosity in young adolescents with auditory vocal hallucinations

The current exploratory study examined the associations between auditory vocal hallucinations (AVH) and delusions and religiosity in young adolescents. 337 children from a population-based case-control study with and without AVH, were assessed after five years at age 12 and 13, on the presence and appraisal of AVH, delusions and religiosity. AVH status (persistent, remittent, incident or control) was examined in relationship to religiosity. Results demonstrated a non-linear association between AVH and religiosity. Moderately religious adolescents were more likely to report AVH than non-religious adolescents (O.R.=2.6). Prospectively, moderately religious adolescents were more likely to have recently developed AVH than non-religious adolescents (O.R.=3.6) and strongly religious adolescents (O.R.=7.9). Of the adolescents reporting voices in this sample (16.3%), more than half reported positive voices. Religious beliefs were often described as supportive, useful or neutral (82%), regardless of the level of religiosity, for both adolescents with and without AVH. Co-occurrence of AVH and delusions, and severity of AVH were not related to religiosity. The present findings suggest there may be a non-linear association between religiosity and hearing voices in young adolescents. A speculative explanation may be that religious practices were adopted in response to AVH as a method of coping.

Social and clinical correlates of the persistence of psychotic experiences in the general population

Recent epidemiological evidence suggests that sub-threshold psychotic experiences commonly occur in the general population. When these experiences persist over time, they may increase risk for psychotic disorder or lead to other clinical or functional impairments. The aims of this study were to distinguish the relative importance of sociodemographic factors and clinical factors, including characteristics of the psychotic experiences themselves, in determining the course of psychotic symptoms over time. Participants were drawn from the Collaborative Psychiatric Epidemiology Surveys. We tested for retrospectively-reported predictors of current psychotic experiences among individuals who reported lifetime psychotic experiences, with onset prior to the past year (n=921), using logistic regression. Persistence was primarily related to demographic variables, with lower odds associated with being married and having at least a college education. Individuals reporting prior to the past year auditory hallucinations were more likely to have persistent psychotic experiences than those reporting other types of psychotic experiences. Interventions aiming at strengthening family support and social skills may reduce the likelihood of persistence among individuals with psychotic experiences, thereby reducing risk for psychotic disorders and other related outcomes. Future studies should continue to identify predictors of persistence versus remission and further explore clinical services for those with persistent psychotic experiences.

The CCC2000 Birth Cohort Study of Register-Based Family History of Mental Disorders and Psychotic Experiences in Offspring

Psychotic experiences (PE) in individuals of the general population are hypothesized to mark the early expression of the pathology underlying psychosis. This notion of PE as an intermediate phenotype is based on the premise that PE share genetic liability with psychosis. We examined whether PE in childhood was predicted by a family history of mental disorder with psychosis rather than a family history of nonpsychotic mental disorder and whether this association differed by severity of PE. The study examined data on 1632 children from a general population birth cohort assessed at age 11-12 years by use of a semistructured interview covering 22 psychotic symptoms. The Danish national registers were linked to describe the complete family history of hospital-based psychiatric diagnoses. Uni- and multivariable logistic regressions were used to test whether a family history of any mental disorder with psychosis, or of nonpsychotic mental disorder, vs no diagnoses was associated with increased risk of PE in offspring (hierarchical exposure variable). The occurrence of PE in offspring was significantly associated with a history of psychosis among the first-degree relatives (adjusted relative risk [RR] = 3.29, 95% CI: 1.82-5.93). The risk increased for combined hallucinations and delusions (adjusted RR = 5.90, 95% CI: 2.64-13.16). A history of nonpsychotic mental disorders in first-degree relatives did not contribute to the risk of PE in offspring nor did any mental disorder among second-degree relatives. Our findings support the notion of PE as a vulnerability marker of transdiagnostic psychosis. The effect of psychosis in first-degree relatives may operate through shared genetic and environmental factors.

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.

Evidence that environmental and genetic risks for psychotic disorder may operate by impacting on connections between core symptoms of perceptual alteration and delusional ideation

BACKGROUND

Relational models of psychopathology propose that symptoms are dynamically connected and hypothesize that genetic and environmental influences moderate the strength of these symptom connections. Previous findings suggest that the interplay between hallucinations and delusions may play a crucial role in the development of psychotic disorder. The current study examined whether the connection between hallucinations and delusions is impacted by proxy genetic and environmental risk factors.

METHODS

Hallucinations and delusions at baseline and at 3-year follow-up were assessed in a sample of 1054 healthy siblings and 918 parents of 1109 patients with psychosis, and in 589 healthy controls (no familial psychosis risk). Environmental factors assessed were cannabis use, childhood trauma, and urbanicity during childhood. Logistic regression analyses tested whether familial psychosis risk predicted increased risk of delusions, given presence of hallucinations. Moderating effects of environmental factors on the hallucination-delusion association were tested in a similar fashion, restricted to the control and sibling groups.

RESULTS

The risk of delusions, given hallucinations, was associated with proxy genetic risk: 53% in parents, 47% in siblings, and 36% in controls. The hallucination-delusion association was stronger in those reporting cannabis use (risk difference: 32%) and childhood trauma (risk difference: 15%) although not all associations were statistically conclusive (respectively: p = .037; p = .054). A directionally similar but nonsignificant effect was found for urb anicity during childhood (risk difference: 14%, p =.357).

CONCLUSION

The strength of the connection between delusions and hallucinations is associated with familial and environmental risks for psychotic disorder, suggesting that specific symptom connections in the early psychosis psychopathology network are informative of underlying mechanisms.

First-rank symptoms and premorbid adjustment in young individuals at increased risk of developing psychosis

BACKGROUND

Individuals at clinical high risk (CHR) for psychosis represent a heterogeneous group with a high rate of comorbid psychiatric disorders. There is little information on whether certain qualitative aspects of psychotic symptoms among CHR individuals may be predictive of future psychosis. This study focused on describing the prevalence of first-rank symptoms (FRS) among a sample of CHR individuals and its association with future transition to psychosis and, from a neurodevelopmental perspective, the level of adjustment of individuals at CHR during their childhood was also analysed.

SAMPLING AND METHODS

Participants comprised 60 individuals at CHR (according to the Comprehensive Assessment of At-Risk Mental States, CAARMS) at the time of their referral to an early intervention service and 60 healthy volunteers (HVs). All subjects were assessed by senior research clinicians using the Mini International Neuropsychiatric Interview (MINI), and the Positive and Negative Syndrome Scale (PANSS). FRS were defined according to Kurt Schneider's original classification, and information was collected from PANSS, CAARMS and clinical reports. Early premorbid functioning was measured using the Premorbid Adjustment Scale (PAS). We grouped individuals by number and type of FRS and analysed transitions to full-blown psychosis over a 2-year follow-up period. We also correlated the general social and functional adjustment of these individuals during their childhood (6-11 years of age) with the future development of mental states at CHR and FRS.

RESULTS

Over 69% of CHR individuals had more than one DSM-IV psychiatric diagnosis, mainly within the affective and anxiety diagnostic spectra. At least one FRS was present in 43.3% of CHR individuals, and 21.6% of these had more than one. Auditory hallucinations and passivity experiences were the most commonly reported. Only 10% of individuals at CHR made a transition to first-episode psychosis (FEP) over 2 years and, except for passivity experiences, the presence of one or more FRS was not significantly associated with the transition to FEP. CHR individuals, especially those with FRS, had poorer premorbid functioning and adjustment as children across educational, social and peer relationship domains than HVs. However, this was not associated with FEP 2 years later.

CONCLUSIONS

FRS might not be indicators of psychosis alone but of different psychiatric disorders. In line with the neurodevelopmental model of psychosis, individuals at CHR might be exhibiting several vulnerability traits and manifestations of abnormal developmental processes that might predict a future psychiatric disorder and/or long-term impairment.

Prevalence and dimensionality of hallucination-like experiences in young adults

BACKGROUND

The study of hallucination-like experiences (HLEs) in non-clinical populations is increasingly used to corroborate etiological models of psychosis. This method capitalizes on the absence of confounding factors that typically affect the study of hallucinations in clinical subjects.

AIM

To estimate the prevalence of HLEs in young adults; validate the mutidimensionality and explore the correlates of latent HLEs clusters.

METHODS

Cross-sectional survey design. The extended 16-item Launay-Slade Hallucination Scale (LSHS-E) and the 12-item General Health Questionnaire (GHQ-12) were administered to 649 Italian college students (males: 47%). Confirmatory factorial analysis was used to test multidimensionality of the LSHS-E. Hierarchical nested, progressively constrained models were used to assess configural, metric and scalar invariance of the LSHS-E. Latent class analysis was used to test the existence of different profiles of responding across the identified hallucination-proneness dimensions.

RESULTS

Factor analysis showed that the four-factor model had the best fit. Factors were invariant across demographic variables and levels of psychological distress. Three latent classes were found: a large class with no HLEs (70% of participants), a multisensory HLEs class (18.8%), and a high hallucination-proneness class (11%). Among those reporting high levels of HLEs, approximately half reported scores indicative of considerable psychological distress.

CONCLUSIONS

Although HLEs have a relatively high prevalence in the general population, the majority of those experiences happen in isolation and are not associated to psychological distress. Approximately half of those individuals experiencing high levels of HLEs report significant psychological distress. This may be indicative of general risk for mental health conditions rather than specific risk for psychosis.

Psychopathological mechanisms linking childhood traumatic experiences to risk of psychotic symptoms: analysis of a large, representative population-based sample

BACKGROUND

Different psychological models of trauma-induced psychosis have been postulated, often based on the observation of "specific" associations between particular types of childhood trauma (CT) and particular psychotic symptoms or the co-occurrence of delusions and hallucinations. However, the actual specificity of these associations remains to be tested.

METHODS

In 2 population-based studies with comparable methodology (Netherlands Mental Health Survey and Incidence Study-1 [NEMESIS-1] and NEMESIS-2, N = 13 722), trained interviewers assessed CT, psychotic symptoms, and other psychopathology. Specificity of associations was assessed with mixed-effects regression models with multiple outcomes, a statistical method suitable to examine specificity of associations in case of multiple correlated outcomes.

RESULTS

Associations with CT were strong and significant across the entire range of psychotic symptoms, without evidence for specificity in the relationship between particular trauma variables and particular psychotic experiences (PEs). Abuse and neglect were both associated with PEs (OR abuse: 2.12, P < .001; OR neglect: 1.96, P < .001), with no large or significant difference in effect size. Intention-to-harm experiences showed stronger associations with psychosis than CT without intent (χ(2) = 58.62, P < .001). Most trauma variables increased the likelihood of co-occurrence of delusions and hallucinations rather than either symptom in isolation.

DISCUSSION

Intention to harm is the key component linking childhood traumatic experiences to psychosis, most likely characterized by co-occurrence of hallucinations and delusions, indicating buildup of psychotic intensification, rather than specific psychotic symptoms in isolation. No evidence was found to support psychological theories regarding specific associations between particular types of CT and particular psychotic symptoms.

Resting-state connectivity deficits associated with impaired inhibitory control in non-treatment-seeking adolescents with psychotic symptoms

OBJECTIVE

Psychotic symptoms are common in the population and index risk for a range of severe psychopathological outcomes. We wished to investigate functional connectivity in a community sample of adolescents who reported psychotic symptoms (the extended psychosis phenotype).

METHOD

This study investigated intrinsic functional connectivity (iFC) during resting-state functional magnetic resonance imaging (fMRI; rs-fMRI). Following screening in schools, 11 non-treatment seeking, youth with psychotic symptoms (aged 11-13) and 14 community controls participated in the study. Seed regions of interest comprised brain regions previously shown to exhibit aberrant activation during inhibitory control in adolescents with psychotic symptoms.

RESULTS

Relative to controls, adolescents with psychotic symptoms exhibited reduced iFC between regions supporting inhibitory control. Specifically, they showed weaker iFC between the right inferior frontal gyrus (IFG) and the cingulate, IFG and the striatum, anterior cingulate and claustrum, and precuneus and supramarginal gyrus. Conversely, the psychotic symptoms group exhibited stronger iFC between the superior frontal gyrus and claustrum and IFG and lingual gyrus.

CONCLUSION

The present findings are the first to reveal aberrant functional connectivity in resting-state networks in a community sample of adolescents with psychotic symptoms and suggest that disruption in integration between distributed neural networks (particularly between prefrontal, cingulate and striatal brain regions) may be a key neurobiological feature of the extended psychosis phenotype.

Evidence that a psychopathology interactome has diagnostic value, predicting clinical needs: an experience sampling study

BACKGROUND

For the purpose of diagnosis, psychopathology can be represented as categories of mental disorder, symptom dimensions or symptom networks. Also, psychopathology can be assessed at different levels of temporal resolution (monthly episodes, daily fluctuating symptoms, momentary fluctuating mental states). We tested the diagnostic value, in terms of prediction of treatment needs, of the combination of symptom networks and momentary assessment level.

METHOD

Fifty-seven patients with a psychotic disorder participated in an ESM study, capturing psychotic experiences, emotions and circumstances at 10 semi-random moments in the flow of daily life over a period of 6 days. Symptoms were assessed by interview with the Positive and Negative Syndrome Scale (PANSS); treatment needs were assessed using the Camberwell Assessment of Need (CAN).

RESULTS

Psychotic symptoms assessed with the PANSS (Clinical Psychotic Symptoms) were strongly associated with psychotic experiences assessed with ESM (Momentary Psychotic Experiences). However, the degree to which Momentary Psychotic Experiences manifested as Clinical Psychotic Symptoms was determined by level of momentary negative affect (higher levels increasing probability of Momentary Psychotic Experiences manifesting as Clinical Psychotic Symptoms), momentary positive affect (higher levels decreasing probability of Clinical Psychotic Symptoms), greater persistence of Momentary Psychotic Experiences (persistence predicting increased probability of Clinical Psychotic Symptoms) and momentary environmental stress associated with events and activities (higher levels increasing probability of Clinical Psychotic Symptoms). Similarly, the degree to which momentary visual or auditory hallucinations manifested as Clinical Psychotic Symptoms was strongly contingent on the level of accompanying momentary paranoid delusional ideation. Momentary Psychotic Experiences were associated with CAN unmet treatment needs, over and above PANSS measures of psychopathology, similarly moderated by momentary interactions with emotions and context.

CONCLUSION

The results suggest that psychopathology, represented as an interactome at the momentary level of temporal resolution, is informative in diagnosing clinical needs, over and above traditional symptom measures.

Mechanisms Underlying Auditory Hallucinations-Understanding Perception without Stimulus

Auditory verbal hallucinations (AVH) are a common phenomenon, occurring in the “healthy” population as well as in several mental illnesses, most notably schizophrenia. Current thinking supports a spectrum conceptualisation of AVH: several neurocognitive hypotheses of AVH have been proposed, including the “feed-forward” model of failure to provide appropriate information to somatosensory cortices so that stimuli appear unbidden, and an “aberrant memory model” implicating deficient memory processes. Neuroimaging and connectivity studies are in broad agreement with these with a general dysconnectivity between frontotemporal regions involved in language, memory and salience properties. Disappointingly many AVH remain resistant to standard treatments and persist for many years. There is a need to develop novel therapies to augment existing pharmacological and psychological therapies: transcranial magnetic stimulation has emerged as a potential treatment, though more recent clinical data has been less encouraging. Our understanding of AVH remains incomplete though much progress has been made in recent years. We herein provide a broad overview and review of this.