Is disorganization a feature of schizophrenia or a modifying influence: evidence of covariation of perceptual and cognitive organization in a non-patient sample

A network analysis of anxiety, depressive, and psychotic symptoms and functioning in children and adolescents at clinical high risk for psychosis

Objective

Youths at clinical high risk for psychosis (CHR-P) are characterized by a high prevalence of anxiety and depressive disorders. The present study aimed at developing and analyzing a network structure of CHR-P symptom domains (i.e., positive, negative, disorganization, and general subclinical psychotic symptoms), depressive and anxiety symptoms, and general functioning.

Methods

Network analysis was applied to data on 111 CHR-P children and adolescents (M age = 14.1), who were assessed using the Structured Interview for Prodromal Syndromes, the Children's Depression Inventory, the Children's Global Assessment Scale, and the Multidimensional Anxiety Scale for Children.

Results

In the network, negative and disorganization symptoms showed the strongest association (r = 0.71), and depressive and anxiety symptoms showed dense within-domain connections, with a main bridging role played by physical symptoms of anxiety. The positive symptom cluster was not associated with any other node. The network stability coefficient (CS) was slightly below 0.25, and observed correlations observed ranged from 0.35 to 0.71.

Conclusion

The lack of association between subclinical positive symptoms and other network variables confirmed the independent nature of subclinical positive symptoms from comorbid symptoms, which were found to play a central role in the analyzed network. Complex interventions should be developed to target positive and comorbid symptoms, prioritizing those with the most significant impact on functioning and the most relevance for the young individual, through a shared decision-making process. Importantly, the results suggest that negative and disorganization symptoms, as well as depressive and anxiety symptoms, may be targeted simultaneously.

Does childhood trauma predict schizotypal traits? A path modelling approach in a cohort of help-seeking subjects

Schizotypy constitutes a susceptibility to beneficial and deleterious schizotypal traits, ranging from coping mechanisms to schizotypal personality disorder on a psychosis continuum. Growing evidence indicates a relationship between childhood adversity and trauma and schizotypy. However, the exact influence of childhood adversity and trauma on schizotypy and its relation to sex is not sufficiently understood. Therefore, we investigated sex-adjusted connections between childhood adversity and trauma subdomains (emotional/physical/sexual abuse, emotional/physical neglect) and positive (magical ideation, perceptual aberration) as well as negative schizotypy (physical/social anhedonia). In total, 240 outpatients of the Early Detection and Intervention Centre of the University Hospital Cologne were assessed with the Trauma and Distress Scale for childhood adversity and trauma and the Wisconsin Schizotypy Scales for schizotypy. Path analyses were performed to investigate sex-adjusted correlations. The well-fitting path model of the total sample linked emotional abuse to magical ideation (p = 0.03; SE = 0.20) and emotional neglect to social anhedonia (p = 0.01; SE = 0.26). In females, physical abuse predicted magical ideation (p = 0.01; SE = 0.33), while emotional neglect forecasted physical anhedonia (p = 0.03; SE = 0.34) and social anhedonia (p = 0.03; SE = 0.32). In males, sexual abuse predicted perceptive aberration (p = 0.04; SE = 0.19) and emotional abuse forecasted magical ideation (p = 0.03; SE = 0.27). Overall, the significance of sex-specific interrelations between trauma and schizotypy were highlighted. Magical ideation and perceptive aberration occurred prominently in the absence of negative and disorganized schizotypy, thus positive schizotypy could be discussed as a beneficial expression of coping with emotional, physical and sexual abuse. Furthermore, emotional neglect should be addressed particularly to prevent deleterious negative schizotypy in females.Trial registration number (20-1243), date of registration (May 19th 2020), retrospectively registered.

Association between cognitive phenotype in unaffected siblings and prospective 3- and 6-year clinical outcome in their proband affected by psychosis

BACKGROUND

Cognitive alterations are a central and heterogeneous trait in psychotic disorders, driven by environmental, familial and illness-related factors. In this study, we aimed to prospectively investigate the impact of high familial risk for cognitive alterations, unconfounded by illness-related factors, on symptomatic outcomes in patients.

METHODS

In total, 629 probands with non-affective psychosis and their sibling not affected by psychosis were assessed at baseline, 3- and 6-year follow-up. Familial cognitive risk was modeled by three cognitive subtypes ('normal', 'mixed' and 'impaired') in the unaffected siblings. Generalized linear mixed models assessed multi-cross-sectional associations between the sibling cognitive subtype and repeated measures of proband symptoms across all assessments. Between-group differences over time were assessed by adding an interaction effect of time and sibling cognitive subtype.

RESULTS

Probands affected by psychosis with a sibling of the impaired cognitive subtype were less likely to be in symptomatic remission and showed more disorganization across all time points. When assessing differences over time, probands of siblings with the impaired cognitive subtype showed less remission and less improvement of disorganization after 3 and 6 years relative to the other subtypes. They also showed less reduction of positive, negative and excitement symptoms at 6-year follow-up compared to probands with a sibling of the normal cognitive subtype.

CONCLUSIONS

Cross-sibling pathways from higher levels of familial cognitive vulnerability to worse long-term outcomes may be informative in identifying cognition-related environmental and genetic risks that impact psychotic illness heterogeneity over time.

Obsessive-Compulsive Symptoms and Other Symptoms of the At-risk Mental State for Psychosis: A Network Perspective

BACKGROUND

The high prevalence of obsessive-compulsive symptoms (OCS) among subjects at Ultra-High Risk (UHR) for psychosis is well documented. However, the network structure spanning the relations between OCS and symptoms of the at risk mental state for psychosis as assessed with the Comprehensive Assessment of At Risk Mental States (CAARMS) has not yet been investigated. This article aimed to use a network approach to investigate the associations between OCS and CAARMS symptoms in a large sample of individuals with different levels of risk for psychosis.

METHOD

Three hundred and forty-one UHR and 66 healthy participants were included, who participated in the EU-GEI study. Data analysis consisted of constructing a network of CAARMS symptoms, investigating central items in the network, and identifying the shortest pathways between OCS and positive symptoms.

RESULTS

Strong associations between OCS and anxiety, social isolation and blunted affect were identified. Depression was the most central symptom in terms of the number of connections, and anxiety was a key item in bridging OCS to other symptoms. Shortest paths between OCS and positive symptoms revealed that unusual thought content and perceptual abnormalities were connected mainly via anxiety, while disorganized speech was connected via blunted affect and cognitive change.

CONCLUSIONS

Findings provide valuable insight into the central role of depression and the potential connective component of anxiety between OCS and other symptoms of the network. Interventions specifically aimed to reduce affective symptoms might be crucial for the development and prospective course of symptom co-occurrence.

Conceptual disorganization and redistribution of resting-state cortical hubs in untreated first-episode psychosis: A 7T study

Network-level dysconnectivity has been studied in positive and negative symptoms of schizophrenia. Conceptual disorganization (CD) is a symptom subtype that predicts impaired real-world functioning in psychosis. Systematic reviews have reported aberrant connectivity in formal thought disorder, a construct related to CD. However, no studies have investigated whole-brain functional correlates of CD in psychosis. We sought to investigate brain regions explaining the severity of CD in patients with first-episode psychosis (FEPs) compared with healthy controls (HCs). We computed whole-brain binarized degree centrality maps of 31 FEPs, 25 HCs, and characterized the patterns of network connectivity in the 2 groups. In FEPs, we related these findings to the severity of CD. We also studied the effect of positive and negative symptoms on altered network connectivity. Compared to HCs, reduced centrality of a right superior temporal gyrus (rSTG) cluster was observed in the FEPs. In patients exhibiting high CD, increased centrality of a medial superior parietal (mSPL) cluster was observed, compared to patients exhibiting low CD. This cluster was strongly correlated with CD scores but not with other symptom scores. Our observations are congruent with previous findings of reduced but not increased centrality. We observed increased centrality of mSPL suggesting that cortical reorganization occurs to provide alternate routes for information transfer. These findings provide insight into the underlying neural processes mediating the presentation of symptoms in untreated FEP. Longitudinal tracking of the symptom course will be useful to assess the mechanisms underlying these compensatory changes.

Heritability of human visual contour integration-an integrated genomic study

Contour integration, a key visual function to deal with occlusion and discontinuity in natural scenes, is essential to human survival. However, individuals are not equally well equipped with this ability. In particular, contour integration deficiencies are commonly detected in patients with mental disorders, especially schizophrenia. To understand the underlying sources of these individual differences, the current study investigated the genetic basis of contour integration in humans. A total of 2619 normal participants were tested on their ability to detect continuous contours embedded in a cluttered background. Quantitative genomic analysis was performed, involving heritability estimation based on single nucleotide polymorphisms (SNPs) and association testing at SNP, gene, and pathway levels. Heritability estimation showed that common SNPs contributed 49.5% (standard error of the mean = 15.6%) of overall phenotypic variation, indicating moderate heritability of contour integration. Two-stage genome-wide association analysis (GWAS) detected four SNPs reaching genome-wide significance in the discovery test (N = 1931) but not passing the replication test (N = 688). Gene-level analysis further revealed a significant genome-wide association of a microRNA-encoding gene MIR1178 in both the discovery and replication cohorts. Another gene poly(A)-binding protein nuclear 1 like, cytoplasmic (PABPN1L) showed suggestive significance in the discovery cohort (p < 1 × 10-4) and was replicated in the replication cohort (p = 0.009). The pathway analysis did not detect any significant pathway. Taken together, this study identified significant gene associations with contour integration and provided support for a genetic transmission of the ability to perceive continuous contours in the environment.

Data gathering ability contributes to visual organization and probabilistic reasoning

Individuals use data gathering methods to inform judgments and behaviors. Effective interaction with the environment depends on these having high accuracy and low noise, but when they become abnormal, aberrant thoughts and perceptions can occur. In this study, we examined if data gathering methods were consistent across tasks that relied on different cognitive abilities, specifically visual perception and probabilistic reasoning. Thirty-four non-clinical participants engaged in the Ebbinghaus Illusion and the Jumping to Conclusions tasks, while also completing questionnaires concerning aspects of delusion formation. A significant, positive correlation was observed between performance on the Ebbinghaus Illusion and the Jumping to Conclusions tasks. Both tasks were negatively correlated with the General Conspiracy Belief Scale. The results suggest an underlying mechanism for data gathering that is consistent across behavioral domains and exists on a continuum in the general population.

Enhanced mental imagery and intact perceptual organization in schizotypal personality disorder

According to a widely held view, psychotic disorders such as schizophrenia are characterized by a vague boundary between the perception of the external world and the inner imagery of persons, objects, and events. In this study, we addressed the perception-imagery debate in schizotypal personality disorder (SPD). Thirty individuals with SPD and 30 matched healthy subjects completed a lateral masking task. Participants were asked to detect a low-contrast Gabor patch flanked by two collinear Gabor masks. In the perceptual task, the masks were physically present, whereas in the imagery task, participants only imagined the masks. By applying a binocular rivalry paradigm, we also measured the imagery priming effect. Results revealed that, in the perceptual task, collinear masks similarly decreased contrast threshold in SPD and controls. In the imagery task, contrast threshold reduction (facilitation by the imagined masks) was more pronounced in SPD relative to the controls. In the binocular rivalry paradigm, individuals with SPD showed higher imagery priming effects as compared to healthy controls. Enhanced imagery was not related to schizotypal traits. These results indicate intact early visual perception and heightened imagery in SPD, which may be a trait marker of unusual experiences without psychotic disorganization.

A review of abnormalities in the perception of visual illusions in schizophrenia

Specific abnormalities of vision in schizophrenia have been observed to affect high-level and some low-level integration mechanisms, suggesting that people with schizophrenia may experience anomalies across different stages in the visual system affecting either early or late processing or both. Here, we review the research into visual illusion perception in schizophrenia and the issues which previous research has faced. One general finding that emerged from the literature is that those with schizophrenia are mostly immune to the effects of high-level illusory displays, but this effect is not consistent across all low-level illusions. The present review suggests that this resistance is due to the weakening of top-down perceptual mechanisms and may be relevant to the understanding of symptoms of visual distortion rather than hallucinations as previously thought.

Sensory integration deficits support a dimensional view of psychosis and are not limited to schizophrenia

Visual dysfunction is commonplace in schizophrenia and occurs alongside cognitive, psychotic and affective symptoms of the disorder. Psychophysical evidence suggests that this dysfunction results from impairments in the integration of low-level neural signals into complex cortical representations, which may also be associated with symptom formation. Despite the symptoms of schizophrenia occurring in a range of disorders, the integration deficit has not been tested in broader patient populations. Moreover, it remains unclear whether such deficits generalize across other sensory modalities. The present study assessed patients with a range of psychotic and nonpsychotic disorders and healthy controls on visual contrast detection, visual motion integration, auditory tone detection and auditory tone integration. The sample comprised a total of 249 participants (schizophrenia spectrum disorder n=98; bipolar affective disorder n=35; major depression n=31; other psychiatric conditions n=31; and healthy controls n=54), of whom 178 completed one or more visual task and 71 completed auditory tasks. Compared with healthy controls and nonpsychotic patients, psychotic patients trans-diagnostically were impaired on both visual and auditory integration, but unimpaired in simple visual or auditory detection. Impairment in visual motion integration was correlated with the severity of positive symptoms, and could not be accounted for by a reduction in processing speed, inattention or medication effects. Our results demonstrate that impaired sensory integration is not specific to schizophrenia, as has previously been assumed. Instead, sensory deficits are closely related to the presence of positive symptoms independent of diagnosis. The finding that equivalent integrative sensory processing is impaired in audition is consistent with hypotheses that propose a generalized deficit of neural integration in psychotic disorders.

Phenomenology and neurobiology of self disorder in schizophrenia: Primary factors

Schizophrenia is a heterogeneous syndrome, varying between persons and over course of illness. In this and a companion article, we argue that comprehension of this condition or set of conditions may require combining a phenomenological perspective emphasizing disorders of basic-self experience ("ipseity disturbance") with a multidimensional appreciation of possible neurobiological correlates--both primary and secondary. Previous attempts to link phenomenology and neurobiology generally focus on a single neurocognitive factor. We consider diverse aspects of schizophrenia in light of a diverse, albeit interacting, set of neurocognitive abnormalities, examining both synchronic (structural) interdependence and diachronic (temporal) succession. In this article we focus on the primary or foundational role of early perceptual and motoric disturbances that affect perceptual organization and especially intermodal or multisensory perceptual integration (“perceptual dys-integration”). These disturbances are discussed in terms of their implications for three interconnected aspects of selfhood in schizophrenia, primary forms of: disrupted "hold" or "grip" on the world, hyperreflexivity, diminished self-presence (self-affection). Disturbances of organization or integration imply forms of perceptual incoherence or diminished cognitive coordination. The effect is to disrupt one's ability to apprehend the world in holistic, vital, or contextually grounded fashion, or to fully identify with or experience the unity of one's own body or thinking--thereby generating an early and profound (albeit often subtle) disruption or diminishment of basic or core self and of the sense of existing in a coherent world. We discuss interrelationships or possible complementarities between these three aspects, and consider their relevance for a neurodevelopmental account of schizophrenia.

Meeting overview: Sensory perception and schizophrenia, Lausanne, Switzerland June 31-July 1, 2014

Schizophrenia is increasingly being viewed as a “whole brain” disorder with deficits affecting widespread cortical and subcortical networks. Within this context, studies of visual cortical function may be particularly important both because visual processing deficits directly affect social and occupational function and because these systems are well characterized at the basic science level, permitting informative translational research. This article summarizes a conference on visual processing dysfunction in schizophrenia held in Lausanne, Switzerland from June 30 to July 1, 2014 and introduces this special issue. Speakers focused on multiple aspects of visual dysfunction in schizophrenia using behavioral, neurophysiological and fMRI-based approaches.

Four main themes emerged. First was a focus on response disturbances within the early visual system, using paradigms such as sensory EEG and MEG-based responses. Second, behavioral deficits were noted in processing related to local interaction within visual regions, using paradigms such as Vernier acuity or contour integration. These deficits provided potential model systems to understand impaired connectivity within the brain in schizophrenia more generally.

Third, several visual measures were found to correlate highly with symptoms and/or neurocognitive processing. Deficits in contour integration, for example, correlated highly with conceptual disorganization, whereas perceptual instability correlated with delusion formation. These findings highlight links between perceptual-level disturbance and clinical manifestation. Finally, the potential involvement of specific neurotransmitter receptors, including N-methyl-D-aspartate (NMDA)-type glutamate receptors and alpha7 nicotinic receptors were discussed as potential etiological mechanisms. Overall, the meeting highlighted the contributions of visual pathway dysfunction to the etiopathogenesis of neurocognitive dysfunction in schizophrenia.

Schizotypy--do not worry, it is not all worrisome

A long-standing tradition in personality research in psychology, and nowadays increasingly in psychiatry, is that psychotic and psychotic-like thoughts are considered common experiences in the general population. Given their widespread occurrence, such experiences cannot merely reflect pathological functioning. Moreover, reflecting the multi-dimensionality of schizotypy, some dimensions might be informative for healthy functioning while others less so. Here, we explored these possibilities by reviewing research that links schizotypy to favorable functioning such as subjective wellbeing, cognitive functioning (major focus on creativity), and personality correlates. This research highlights the existence of healthy people with psychotic-like traits who mainly experience positive schizotypy (but also affective features mapping onto bipolar disorder). These individuals seem to benefit from a healthy way to organize their thoughts and experiences, that is, they employ an adaptive cognitive framework to explain and integrate their unusual experiences. We conclude that, instead of focusing only on the pathological, future studies should explore the behavioral, genetic, imaging, and psychopharmacological correlates that define the healthy expression of psychotic-like traits. Such studies would inform on protective or compensatory mechanisms of psychosis-risk and could usefully inform us on the evolutionary advantages of the psychosis dimension.

Contour integration impairment in schizophrenia and first episode psychosis: state or trait?

Contour integration is a fundamental visual process that recovers object structure by representing spatially separated edge elements as a continuous contour or shape boundary. Clinically stable persons with schizophrenia have repeatedly been shown to be impaired at contour integration but it is unclear whether this process varies with clinical state or whether it arises as early as the first episode of psychosis. To consider these issues, we administered a contour integration test to persons with chronic schizophrenia and to those with a first episode of psychosis. The test was administered twice-once at admission to short term psychiatric hospitalization and once again at discharge. A well-matched healthy control group was also tested across the same time points. We found that contour integration performance improved to the same degree in all groups over time, indicating that there were no recovery effects over and above normal practice effects. Moreover, the schizophrenia group demonstrated poorer contour integration than the control group and the first episode group exhibited intermediate performance that could not be distinguished from the other groups. These results suggest that contour integration ability does not vary as a function of short-term changes in clinical state, and that it may become further impaired with an increased number of psychotic episodes.