The crisis of minimal self-awareness in schizophrenia: a meta-analytic review

Bodily experiences of trauma and psychosis risk

Bodily self-disturbances including anomalous embodiment of emotions are observed in psychosis-spectrum conditions. Psychosis is also associated with trauma exposure but the relationship between altered bodily experiences and trauma has not been extensively investigated in individuals at risk for psychosis (HR). We implemented a mapping task to localize felt sensations associated with trauma. Results show that trauma experiences were always localized in the body. HR reported increased rates of traumatic experiences than low-risk group (LR). HR reported sensations associated with trauma across widespread body areas. Further research is needed to elucidate how trauma might lead to psychotic-like experiences via bodily self-disturbances.

Probing corporeal awareness in women through virtual reality induction of embreathment illusion

We capitalized on the respiratory bodily illusion that we discovered in a previous study and called 'Embreathment' where we showed that breathing modulates corporeal awareness in men. Despite the relevance of the issue, no such studies are available in women. To bridge this gap, we tested whether the synchronization of avatar-participant respiration patterns influenced females' bodily awareness. We collected cardiac and respiratory interoceptive measures, administered body (dis)satisfaction questionnaires, and tracked participants' menstrual cycles via a mobile app. Our approach allowed us to characterize the 'Embreathment' illusion in women, and explore the relationships between menstrual cycle, interoception and body image. We found that breathing was as crucial as visual appearance in eliciting feelings of ownership and held greater significance than any other cue with respect to body agency in both women and men. Moreover, a positive correlation between menstrual cycle days and body image concerns, and a negative correlation between interoceptive sensibility and body dissatisfaction were found, confirming that women's body dissatisfaction arises during the last days of menstrual cycle and is associated with interoception. These findings have potential implications for corporeal awareness alterations in clinical conditions like eating disorders and schizophrenia.

Interplay between childhood trauma, bodily self-disturbances, and clinical phenomena in schizophrenia spectrum disorders: A network analysis

BACKGROUND

Bodily self-disturbances have long been considered central to schizophrenia. Exposure to childhood trauma has been linked to the development of both psychosis and bodily self-disturbances, yet little work has examined the role of bodily self-disturbances in the relationship between childhood trauma and schizophrenia symptomatology. This study uses network analysis to bridge this gap.

METHODS

Networks were constructed to examine relationships between schizophrenia symptoms (Positive and Negative Symptom Scale; PANSS), bodily self-disturbances (Perceptual Aberration Scale; PAS), and self-reported exposure to childhood trauma (Childhood Trauma Questionnaire, Short-Form; CTQ-SF) in 152 people with a schizophrenia-spectrum disorder. Shortest path and bridge analyses were conducted to assess the role of bodily self-disturbances in linking childhood trauma to schizophrenia symptomatology. Three networks were constructed: 1) PAS, childhood trauma, and PANSS sub-scale composites (positive, negative, general); 2) PAS, childhood trauma, and positive symptoms, 3) PAS, childhood trauma, and distress symptoms.

RESULTS

Shortest path analysis revealed that bodily self-disturbances were on the shortest path between childhood trauma and positive and general symptoms (Network 1), between trauma and hallucinations (Network 2), and between trauma and depression (Network 3). Bodily self-disturbances were also found to serve as a bridge between childhood trauma and positive symptoms of schizophrenia, particularly delusions and hallucinations.

CONCLUSIONS

Using a novel, data-driven approach, we showed that bodily self-disturbances play a key role in linking childhood trauma to positive and co-morbid affective symptoms of schizophrenia. Threat experiences (i.e., abuse) specifically relate to bodily self-disturbances and psychotic symptoms.

The schizophrenia syndrome, circa 2024: What we know and how that informs its nature

With new data about different aspects of schizophrenia being continually generated, it becomes necessary to periodically revisit exactly what we know. Along with a need to review what we currently know about schizophrenia, there is an equal imperative to evaluate the construct itself. With these objectives, we undertook an iterative, multi-phase process involving fifty international experts in the field, with each step building on learnings from the prior one. This review assembles currently established findings about schizophrenia (construct, etiology, pathophysiology, clinical expression, treatment) and posits what they reveal about its nature. Schizophrenia is a heritable, complex, multi-dimensional syndrome with varying degrees of psychotic, negative, cognitive, mood, and motor manifestations. The illness exhibits a remitting and relapsing course, with varying degrees of recovery among affected individuals with most experiencing significant social and functional impairment. Genetic risk factors likely include thousands of common genetic variants that each have a small impact on an individual's risk and a plethora of rare gene variants that have a larger individual impact on risk. Their biological effects are concentrated in the brain and many of the same variants also increase the risk of other psychiatric disorders such as bipolar disorder, autism, and other neurodevelopmental conditions. Environmental risk factors include but are not limited to urban residence in childhood, migration, older paternal age at birth, cannabis use, childhood trauma, antenatal maternal infection, and perinatal hypoxia. Structural, functional, and neurochemical brain alterations implicate multiple regions and functional circuits. Dopamine D-2 receptor antagonists and partial agonists improve psychotic symptoms and reduce risk of relapse. Certain psychological and psychosocial interventions are beneficial. Early intervention can reduce treatment delay and improve outcomes. Schizophrenia is increasingly considered to be a heterogeneous syndrome and not a singular disease entity. There is no necessary or sufficient etiology, pathology, set of clinical features, or treatment that fully circumscribes this syndrome. A single, common pathophysiological pathway appears unlikely. The boundaries of schizophrenia remain fuzzy, suggesting the absence of a categorical fit and need to reconceptualize it as a broader, multi-dimensional and/or spectrum construct.

Agency in schizophrenia and autism: a systematic review

Introduction

Previous research suggests that altered experiences of agency are an underlying vulnerability in both schizophrenia and autism. Here, we explore agency as a potential transdiagnostic factor by conducting a systematic review of existing literature investigating agency in autism and schizophrenia individually and together.

Methods

Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, we conducted three systematic searches on PsycINFO, Embase, Medline, PubMed and Web of Science to identify studies that investigated (1) agency in schizophrenia, (2) agency in autism, and (3) agency in both schizophrenia and autism.

Results

A total of 31 articles met eligibility criteria for inclusion and data extraction, with 24 measuring agency in schizophrenia, 7 investigating agency in autism, and no articles comparing the two. Results show that, compared to control populations, agency is significantly different in every identified schizophrenia study and generally not significantly different in autism.

Discussion

Importantly, we identified a lack of studies using common tasks and a disproportionate number of studies investigating different dimensions of agency across the two conditions, resulting in limited grounds for valid comparison.

Systematic review registration

Prospero, CRD42021273373.

The bodily self from psychosis to psychedelics

The sense of self is a foundational element of neurotypical human consciousness. We normally experience the world as embodied agents, with the unified sensation of our selfhood being nested in our body. Critically, the sense of self can be altered in psychiatric conditions such as psychosis and altered states of consciousness induced by psychedelic compounds. The similarity of phenomenological effects across psychosis and psychedelic experiences has given rise to the "psychotomimetic" theory suggesting that psychedelics simulate psychosis-like states. Moreover, psychedelic-induced changes in the sense of self have been related to reported improvements in mental health. Here we investigated the bodily self in psychedelic, psychiatric, and control populations. Using the Moving Rubber Hand Illusion, we tested (N = 75) patients with psychosis, participants with a history of substantial psychedelic experiences, and control participants to see how psychedelic and psychiatric experience impacts the bodily self. Results revealed that psychosis patients had reduced Body Ownership and Sense of Agency during volitional action. The psychedelic group reported subjective long-lasting changes to the sense of self, but no differences between control and psychedelic participants were found. Our results suggest that while psychedelics induce both acute and enduring subjective changes in the sense of self, these are not manifested at the level of the bodily self. Furthermore, our data show that bodily self-processing, related to volitional action, is disrupted in psychosis patients. We discuss these findings in relation to anomalous self-processing across psychedelic and psychotic experiences.

Schizophrenia in the mind, the brain and the body

The author describes three lines of research programs that have guided her goal of elucidating the etiology of schizophrenia: working memory and representational guidance of behavior, disrupted social cognition and bodily-self disturbances.

Lower cohesion and altered first-person pronoun usage in the spoken life narratives of individuals with schizophrenia

Usage of computational tools to quantify language disturbances among individuals with psychosis is increasing, improving measurement efficiency and access to fine-grained constructs. However, few studies apply automated linguistic analysis to life narratives in this population. Such research could facilitate the measurement of psychosis-relevant constructs such as sense of agency, capacity to organize one's personal history, narrative richness, and perceptions of the roles that others play in one's life. Furthermore, research is needed to understand how narrative linguistic features relate to cognitive and social functioning. In the present study, individuals with schizophrenia (n = 32) and individuals without a psychotic disorder (n = 15) produced personal life narratives within the Indiana Psychiatric Illness Interview. Narratives were analyzed using the Coh-Metrix computational tool. Linguistic variables analyzed were indices of connections within causal and goal-driven speech (deep cohesion), unique word usage (lexical diversity), and pronoun usage. Individuals with schizophrenia compared to control participants produced narratives that were lower in deep cohesion, contained more first-person singular pronouns, and contained fewer first-person plural pronouns. Narratives did not significantly differ between groups in lexical diversity, third-person pronoun usage, or total word count. Cognitive-linguistic relationships emerged in the full sample, including significant correlations between greater working memory capacity and greater deep cohesion and lexical diversity. In the schizophrenia group, social problem-solving abilities did not correlate with linguistic variables but were associated with cognition. Findings highlight the relevance of psychotherapies which aim to promote recovery among individuals with psychosis through the construction of coherent life narratives and increasing agency and social connectedness.

They have taken out my spinal cord: an interpretative phenomenological analysis of self-boundary in psychotic experience within a sociocentric culture

INTRODUCTION

In the tradition of phenomenological psychiatry, schizophrenia is described as a disturbance of the minimal self, i.e. the most basic form of self-awareness. This disturbance of the minimal self at the individual level is assumed to precede the intersubjective disturbances such as boundary weakening. However, the role of intersubjective disturbances in the emergence and recovery of schizophrenic experience still remains an open question. This phenomenological study focuses on how encounters with others shape self-experience during from psychosis by analyzing this process from the perspective of cultural differences, which in current research is especially under-researched. While most phenomenological accounts are based on first person-accounts from Western, individualist cultures where the self is conceived and experienced as separate to others, the present study qualitatively investigates psychotic experiences of patients from Jaffna, Sri Lanka.

METHOD

Semi-structured interviews were conducted with three participants with a diagnosis of schizophrenia or first episode psychosis. The interviews were transcribed and analyzed using interpretative phenomenological analysis (IPA). Eight group experiential themes were identified across interviews.

RESULTS

The data suggest that intersubjective processes of boundary weakening such as invasiveness and hyperattunement may shape minimal self-experience and more specifically contribute to a mistrust of the own senses and to hyper-reflexivity. Interestingly, boundary weakening yields pervasive emotions and can be experienced as a threat to the whole social unit. On the one hand, the strengthening of self-other-boundary was achieved through opposition, closedness and withdrawal from others. On the other hand, this study suggests that the re-opening of self-other-boundaries in response to the crisis may help establish connectedness and may lead to recovery.

Attachment Style and Self-Experience: The Association Between Attachment Style and Self-Reported Altered Self-Experience in Patients With Psychotic Disorders, Unaffected Siblings, and Healthy Controls

ABSTRACT

The present study aimed to examine the cross-sectional association between attachment style and self-reported disturbed self-awareness (disturbed sense of mineness of experiences) and depersonalization (disturbed sense of first-person perspective) in patients with psychotic disorders, unaffected siblings, and healthy controls. Data pertain to a subsample of the GROUP (Genetic Risk and Outcome of Psychosis) study. We found positive associations between anxious attachment and disturbed self-awareness and depersonalization across participants with different psychosis vulnerability. We also found a positive association between avoidant attachment and depersonalization, although on a trend level. Findings indicate that attachment style is associated with self-reported disturbed self-awareness and depersonalization over and above the influence of psychotic or depressive experiences in people across the vulnerability spectrum of psychosis. This supports the importance of attachment style, self-awareness, and depersonalization as potential targets in prevention and treatment interventions in patients with psychotic disorders or those with increased vulnerability.

Recurrence quantification analysis of periodic dynamics in the default mode network in first-episode drug-naïve schizophrenia

Abnormal functional connectivity (FC) within the default model network (DMN) in schizophrenia has been frequently reported in previous studies. However, traditional FC analysis was mostly linear correlations based, with the information on nonlinear or temporally lagged brain signals largely overlooked. Fifty-five first-episode drug-naïve schizophrenia (FES) patients and 53 healthy controls (HCs) underwent resting-state functional magnetic resonance imaging scanning. The DMN was extracted using independent component analysis. Recurrence quantification analysis was used to measure the duration, predictability, and complexity of the periodic processes of the nonlinear DMN time series. The Mann‒Whitney U test was conducted to compare these features between FES patients and HCs. The support vector machine was applied to discriminate FES from HCs based on these features. Determinism, which means predictability of periodic process activity, between the ventromedial prefrontal cortex (vMPFC) and posterior cingulate and between the vMPFC and precuneus, was significantly decreased in FES compared with HCs. Determinism between the vMPFC and precuneus was positively correlated with category fluency scores in FES. The classifier achieved 77% accuracy. Our results suggest that synchronized periodicity among DMN brain regions is dysregulated in FES, and the periodicity in BOLD signals may be a promising indicator of brain functional connectivity.

An evolutionary account of impairment of self in cognitive disorders

Recent research has proposed that certain aspects of psychosis, as experienced in, e.g., schizophrenia (SCZ), but also aspects of other cognitive conditions, such as autism spectrum disorders (ASD) and synesthesia, can be related to a shattered sense of the notion of self. In this paper, our goal is to show that altered processing of self can be attributed to an abnormal functioning of cortico-striatal brain networks supporting, among other, one key human distinctive cognitive ability, namely cross-modality, which plays multiple roles in human cognition and language. Specifically, our hypothesis is that this cognitive mechanism sheds light both on some basic aspects of the minimal self and on some aspects related to higher forms of self, such as the narrative self. We further link the atypical functioning in these conditions to some recent evolutionary changes in our species, specifically, an atypical presentation of human self-domestication (HSD) features. In doing so, we also lean on previous work concerning the link between cognitive disorders and language evolution under the effects of HSD. We further show that this approach can unify both linguistic and non-linguistic symptoms of these conditions through deficits in the notion of self. Our considerations provide further support for the hypothesis that SCZ and ASD are diametrically opposed cognitive conditions, as well for the hypothesis that their etiology is associated with recent human evolution, leading to a deeper understanding of the causes and symptoms of these disorders, and providing new cues, which can be used for an earlier and more accurate diagnostics.

Impaired sense of agency and associated confidence in psychosis

The Sense of Agency (SoA), our sensation of control over our actions, is a fundamental mechanism for delineating the Self from the environment and others. SoA arises from implicit processing of sensorimotor signals as well as explicit higher-level judgments. Psychosis patients suffer from difficulties in the sense of control over their actions and accurate demarcation of the Self. Moreover, it is unclear if they have metacognitive insight into their aberrant abilities. In this pre-registered study, we examined SoA and its associated confidence judgments using an embodied virtual reality paradigm in psychosis patients and controls. Our results show that psychosis patients not only have a severely reduced ability for discriminating their actions but they also do not show proper metacognitive insight into this deficit. Furthermore, an exploratory analysis revealed that the SoA capacities allow for high levels of accuracy in clinical classification of psychosis. These results indicate that SoA and its metacognition are core aspects of the psychotic state and provide possible venues for understanding the underlying mechanisms of psychosis, that may be leveraged for novel clinical purposes.

Sense of body ownership and body agency in schizophrenia

Recent research suggests that embodiment sensations (sense of body ownership and sense of body agency) are altered in schizophrenia. Using a mirror box illusion setup, we tested if the anomalous embodiment experience depends on deficient processing of visuomotor synchrony, disrupted processing of movement mode, or both. The task required participants to press a lever with their index while looking at the image of the experimenter's hand moving on a similar lever. The illusion of embodiment could arise because looking toward the direction of their own hand the participant saw the reflection of the experimenter's hand visually superimposed to his own one through a mirror. During the illusion induction, we systematically varied visuomotor asynchrony (4 delays were imposed on the movement of the experimenter's hand) and the mode of movement (the participant could perform active vs. passive movements). The strength of the illusion of embodiment of the external hand was assessed with explicit judgments of ownership and agency. Patients' data showed an anomalous modulation of ownership with respect to visuomotor synchrony manipulation and an altered modulation of agency with respect to both visuomotor synchrony and movement mode manipulations. Results from the present study suggest that impairments affecting both the processing of temporal aspects of visuomotor signals and the processing of type of movement underlie anomalous embodiment sensations in schizophrenia. Hypotheses about potential deficits accounting for our results are proposed.

Neural Correlates of Variation in Personal Space and Social Functioning in Schizophrenia and Healthy Individuals

BACKGROUND

Changes in the regulation of interpersonal distance, or "personal space" (PS), have been repeatedly observed in schizophrenia and, in some studies, linked to negative symptoms. However, the neurobiological basis of these impairments is poorly understood.

METHODS

Personal space measurements, functional connectivity of a brain network sensitive to intrusions into PS, and symptoms of social withdrawal and anhedonia were assessed, and associations among these outcomes measured, in 33 individuals with a psychotic disorder (primarily schizophrenia [SCZ]) and 36 control subjects (CON).

RESULTS

Personal space size was significantly higher (P = .002) and PS permeability (reflecting the capacity to tolerate intrusions into PS) was significantly lower (P = .021) in the SCZ relative to the CON group, and both measures were significantly correlated with social anhedonia and withdrawal in the full sample (all P < .007). Moreover, functional connectivity between the PS and default mode (DM) networks was significantly correlated with the permeability, but not the size, of PS in the full sample and in the SCZ and CON groups separately, and with social withdrawal in the SCZ group. Lastly, the association between PS-DM network connectivity and social withdrawal in the SCZ group was fully mediated by PS permeability.

DISCUSSION

Neural and behavioral aspects of PS regulation are linked to social motivation in both healthy individuals and those with psychotic disorders, suggesting that measurements of PS could serve as transdiagnostic markers of social functioning.

What is Pain-Related Suffering? Conceptual Critiques, Key Attributes, and Outstanding Questions

Suffering holds a central place within pain research, theory, and practice. However, the construct of pain-related suffering has yet to be operationalized by the International Association for the Study of Pain and is largely underdeveloped. Eric Cassell's seminal work on suffering serves as a conceptual anchor for the limited pain research that specifically addresses this construct. Yet, important critiques of Cassell's work have not been integrated within the pain literature. This Focus Article aims to take a preliminary step towards an updated operationalization of pain-related suffering by 1) presenting key attributes of pain-related suffering derived from a synthesis of the literature and 2) highlighting key challenges associated with Cassell's conceptualization of suffering. We present 4 key attributes: 1) pain and suffering are inter-related, but distinct experiences, 2) suffering is a subjective experience, 3) the experience of suffering is characterized by a negative affective valence, and 4) disruption to one's sense of self is an integral part of suffering. A key outstanding challenge is that suffering is commonly viewed as a self-reflective and future-oriented process, which fails to validate many forms of suffering and marginalizes certain populations. Future research addressing different modes of suffering - with and without self-reflection - are discussed. PERSPECTIVE: This article offers a preliminary step toward operationalizing the construct of pain-related suffering and proposes priorities for future research. A robust operationalization of this construct is essential to developing clinical strategies that aim to better recognize and alleviate suffering among people living with pain.

Interoceptive functioning in schizophrenia and schizotypy

Though bodily self-disturbances are well documented in schizophrenia, interoceptive functioning (i.e., the perception of the internal state of the body) remains poorly understood in this population. In fact, only two studies to date have empirically measured interoceptive ability in schizophrenia. Both studies documented a deficit in interoceptive accuracy (i.e., the objective performance on a heartbeat detection task), and one noted differences in interoceptive sensibility (i.e., the subjective experience of interoception) in this population. To our knowledge, interoceptive awareness (i.e., the metacognitive awareness of one's interoceptive ability) has never been measured in schizophrenia and the link between interoceptive functioning and schizotypy remains unexplored. The present study addresses this gap by investigating the three dimensions of interoception in individuals with schizophrenia and matched controls (Experiment 1, N = 58) and in relation to schizotypal traits (Experiment 2, N = 109). Consistent with the literature, Experiment 1 documented a deficit in interoceptive accuracy and differences in interoceptive sensibility in individuals with schizophrenia. For the first time, our study revealed intact interoceptive awareness in individuals with schizophrenia. Against our expectations, we found no link between schizotypy and interoceptive functioning in Experiment 2. Our novel findings bear important clinical implications as insight into one's interoceptive limitations (i.e., intact interoceptive awareness) might promote treatment seeking behavior in schizophrenia. The lack of association between interoceptive ability and schizotypy in non-help-seeking youths suggests that changes in interoception may only arise with the onset of psychosis.

An evolutionary view of self-awareness

The capacity to be self-aware is regarded as a fundamental difference between humans and other species. However, growing evidence challenges this notion, indicating that many animals show complex signs and behaviors that are consonant with self-awareness. In this review, we suggest that many animals are indeed self-aware, but that the complexity of this process differs among species. We discuss this topic by addressing several different questions regarding self-awareness: what is self-awareness, how has self-awareness been studied experimentally, which species may be self-aware, what are its potential adaptive advantages. We conclude by proposing alternative models for the emergence of self-awareness in relation to species evolutionary paths, indicating future research questions to advance this field further.

Self-disorders and psychopathology: a systematic review

In foundational texts on schizophrenia, the mental disorder was constitutively linked to a specific disintegration of subjectivity (often termed a self-disorder). Apart from Scharfetter's work on ego-pathology, research on self-disorders generally faded into oblivion, and self-disorders were only rediscovered as notable psychopathological features of the schizophrenia spectrum nearly two decades ago. Subsequently, the Examination of Anomalous Self-Experience (EASE) scale was constructed to allow systematic assessment of non-psychotic self-disorders. This Review is the first systematic review of empirical studies on self-disorders based on the EASE or other related scales. The results consistently show that self-disorders hyper-aggregate in schizophrenia spectrum disorders but not in other mental disorders; that self-disorders are found in individuals at a clinical risk of developing psychosis; that self-disorders show a high degree of temporal stability; that self-disorders predict the later development of schizophrenia spectrum disorders; and that self-disorders correlate with the canonical dimensions of the psychopathology of schizophrenia, impaired social functioning, and suicidality. Issues with the methods of the reviewed literature are critically discussed and the role of self-disorders in clinical psychiatry and future research is outlined.

Fronto-Temporal Disconnection Within the Presence Hallucination Network in Psychotic Patients With Passivity Experiences

Psychosis, characterized by hallucinations and delusions, is a common feature of psychiatric disease, especially schizophrenia. One prominent theory posits that psychosis is driven by abnormal sensorimotor predictions leading to the misattribution of self-related events. This misattribution has been linked to passivity experiences (PE), such as loss of agency and, more recently, to presence hallucinations (PH), defined as the conscious experience of the presence of an alien agent while no person is actually present. PH has been observed in schizophrenia, Parkinson's disease, and neurological patients with brain lesions and, recently, the brain mechanisms of PH (PH-network) have been determined comprising bilateral posterior middle temporal gyrus (pMTG), inferior frontal gyrus (IFG), and ventral premotor cortex (vPMC). Given that the experience of an alien agent is a common feature of PE, we here analyzed the functional connectivity within the PH-network in psychotic patients with (N = 39) vs without PE (N = 26). We observed reduced fronto-temporal functional connectivity in patients with PE compared to patients without PE between the right pMTG and the right and left IFG of the PH-network. Moreover, when seeding from these altered regions, we observed specific alterations with brain regions commonly linked to auditory-verbal hallucinations (such as Heschl's gyrus). The present connectivity findings within the PH-network extend the disconnection hypothesis for hallucinations to the specific case of PH and associates the PH-network with key brain regions for frequent psychotic symptoms such as auditory-verbal hallucinations, showing that PH are relevant to the study of the brain mechanisms of psychosis and PE.

Narrative identity in the psychosis spectrum: A systematic review and developmental model

Individuals with schizophrenia-spectrum disorders face profound challenges as they attempt to maintain identity through the course of illness. Narrative identity-the study of internalized, evolving life stories-provides a rich theoretical and empirical perspective on these challenges. Based on evidence from a systematic review of narrative identity in the psychosis spectrum (30 studies, combined N = 3859), we argue that the narrative identities of individuals with schizophrenia-spectrum disorders are distinguished by three features: disjointed structure, a focus on suffering, and detached narration. Psychotic disorders typically begin to emerge during adolescence and emerging adulthood, which are formative developmental stages for narrative identity, so it is particularly informative to understand identity disturbances from a developmental perspective. We propose a developmental model in which a focus on suffering emerges in childhood; disjointed structure emerges in middle and late adolescence; and detached narration emerges before or around the time of a first psychotic episode. Further research with imminent risk and early course psychosis populations would be needed to test these predictions. The disrupted life stories of individuals on the psychosis spectrum provide multiple rich avenues for further research to understand narrative self-disturbances.

Linking RDoC and HiTOP: A new interface for advancing psychiatric nosology and neuroscience

The Research Domain Criteria (RDoC) and the Hierarchical Taxonomy of Psychopathology (HiTOP) represent major dimensional frameworks proposing two alternative approaches to accelerate progress in the way psychopathology is studied, classified, and treated. RDoC is a research framework rooted in neuroscience aiming to further the understanding of transdiagnostic biobehavioral systems underlying psychopathology and ultimately inform future classifications. HiTOP is a dimensional classification system, derived from the observed covariation among symptoms of psychopathology and maladaptive traits, which seeks to provide more informative research and treatment targets (i.e., dimensional constructs and clinical assessments) than traditional diagnostic categories. This article argues that the complementary strengths of RDoC and HiTOP can be leveraged in order to achieve their respective goals. RDoC's biobehavioral framework may help elucidate the underpinnings of the clinical dimensions included in HiTOP, whereas HiTOP may provide psychometrically robust clinical targets for RDoC-informed research. We present a comprehensive mapping between dimensions included in RDoC (constructs and subconstructs) and HiTOP (spectra and subfactors) based on narrative review of the empirical literature. The resulting RDoC-HiTOP interface sheds light on the biobehavioral correlates of clinical dimensions and provides a broad set of dimensional clinical targets for etiological and neuroscientific research. We conclude with future directions and practical recommendations for using this interface to advance clinical neuroscience and psychiatric nosology. Ultimately, we envision that this RDoC-HiTOP interface has the potential to inform the development of a unified, dimensional, and biobehaviorally-grounded psychiatric nosology.

The inside of me: interoceptive constraints on the concept of self in neuroscience and clinical psychology

Humans are unique in their ability to think about themselves and carry a more or less clear notion of who they are in their mind. Here we review recent evidence suggesting that the birth, maintenance, and loss of the abstract concept of 'self' is deeply tied to interoception, the sense of internal physiological signals. Interoception influences multiple facets of the self-concept, cutting across its material, social, moral, and agentive components. Overall, we argue that interoception contributes to the stability of the self-concept over time, unifying its layers and constraining the degree to which it is susceptible to external influences. Hence, the core features of the self-concept are those that correlate more with inner bodily states. We discuss the implications that this may have for theories of embodied cognition as well as for the understanding of psychiatric disorders in which the concept of self appears fragmented or loose. Finally, we formulate some empirical predictions that could be tested in future studies to shed further light on this emerging field.

Abnormal ERPs and Brain Dynamics Mediate Basic Self Disturbance in Schizophrenia: A Review of EEG and MEG Studies

Background: Interest in disordered sense of self in schizophrenia has recently re-emerged in the literature. It has been proposed that there is a basic self disturbance, underlying the diagnostic symptoms of schizophrenia, in which the person's sense of being a bounded individual continuous through time loses stability. This disturbance has been documented phenomenologically and at the level of cognitive tasks. However, the neural correlates of basic self disorder in schizophrenia are poorly understood. Methods: A search of PubMed was used to identify studies on self and schizophrenia that reported EEG or MEG data. Results: Thirty-three studies were identified, 32 using EEG and one using MEG. Their operationalizations of the self were divided into six paradigms: self-monitoring for errors, proprioception, self-other integration, self-referential processing, aberrant salience, and source monitoring. Participants with schizophrenia were less accurate on self-referential processing tasks and had slower response times across most studies. Event-related potential amplitudes differed across many early and late components, with reduced N100 suppression in source monitoring paradigms being the most replicated finding. Several studies found differences in one or more frequency band, but no coherent overall finding emerged in this area. Various other measures of brain dynamics also showed differences in single studies. Only some of the study designs were adequate to establish a causal relationship between the self and EEG or MEG measures. Conclusion: The broad range of changes suggests a global self disturbance at the neuronal level, possibly carried over from the resting state. Further studies that successfully isolate self-related effects are warranted to better understand the temporal-dynamic and spatial-topographic basis of self disorder and its relationship to basic self disturbance on the phenomenological level.

The Self in the Spectrum: A Meta-analysis of the Evidence Linking Basic Self-Disorders and Schizophrenia

Disturbed self-experience has been reported as a characteristic feature of schizophrenia since the first formulation of its diagnostic concept; however, only in the last 2 decades an explicit notion of basic Self-disturbance, or Self-Disorders (SD), has emerged as target for a systematic research program. We conducted systematic searches in bibliographical databases to identify cross-sectional studies that explored SD across different diagnostic groups and explored diagnostic ascription within or outside schizophrenia spectrum disorders (SSD) as main outcome. Data were pooled using fixed- and random-effects meta-analysis models. Heterogeneity was assessed using stratified meta-analyses and meta-regression. Of 218 identified studies, 32 were included in the systematic review and 27 in the meta-analysis. Patients diagnosed with SSD scored higher on measures of SD than healthy controls (HC) (Hedges' g = 1.8; 95% CI = 1.5 to 2.0), individuals diagnosed with other mental illness (OMI) (1.9; 1.6 to 2.2), bipolar or affective disorders (1.8; 1.4 to 2.2), and clinical high risk for psychosis (CHR) (1.6; 0.9 to 2.4). Patients with schizotypy or schizotypal personality disorder scored higher on measures of SD than OMI (1.5; 1.3 to 1.8) and HC (1.4; 1.1 to 1.7). Patients with first-episode psychosis scored higher on measures of SD than HC (2.5; 2.1 to 2.9) and OMI (1.6; 1.2 to 2.1). Subjects at CHR scored higher on measures of SD than HC (2.0; 1.7 to 2.2) and OMI (19; 1.6 to 2.2). Overall, heterogeneity ranged from negligible to high, especially in comparisons of the target group with OMI, probably as a reflection of the immanent diagnostic heterogeneity of this group. The findings suggest that SD selectively aggregate within schizophrenia spectrum disorders as compared to other mental disorders and that they could be a central phenotypic marker of vulnerability to schizophrenia across the different shades of severity of its spectrum of disorders.

Neural Correlates of Self-other Distinction in Patients with Schizophrenia Spectrum Disorders: The Roles of Agency and Hand Identity

Schizophrenia spectrum disorders (SSD) are characterized by disturbed self-other distinction. While previous studies associate abnormalities in the sense of agency (ie, the feeling that an action and the resulting sensory consequences are produced by oneself) with disturbed processing in the angular gyrus, passive movement conditions to isolate contributions of motor predictions are lacking. Furthermore, the role of body identity (ie, visual features determining whether a seen body part belongs to oneself) in self-other distinction is unclear. In the current study, fMRI was used to assess the roles of agency and hand identity in self-other distinction. Patients with SSD and healthy controls (HC) performed active and passive hand movements (agency manipulation) while seeing their own or someone else's hand moving in accordance with their action (hand identity manipulation). Variable delays (0-417 ms) between movement and feedback had to be detected. Our results showed overall lower delay detection performances during active than passive conditions; however, these differences were reduced in patients when the own hand was displayed. On a neural level, we found that in HC, activation in the right angular gyrus was modulated by agency and hand identity. In contrast, agency and hand identity revealed no overlapping activation in patients, due to reduced effects of agency. Importantly, HC and SSD patients shared similar effects of hand identity in the angular gyrus. Our results suggest that disturbances of self-other distinction in SSD are particularly driven by agency, while self-other distinction based on hand identity might be spared.

Reduced Jumping to Conclusion Bias after Experimentally Induced Enhancement of Subjective Body Boundaries in Psychosis

INTRODUCTION

A disturbed sense of self is frequently discussed as an etiological factor for delusion symptoms in psychosis. Phenomenological approaches to psychopathology posit that lacking the sense that the self is localized within one's bodily boundaries (disembodiment) is one of the core features of the disturbed self in psychosis. The present study examines this idea by experimentally manipulating the sense of bodily boundaries.

METHODS

Seventy-three patients with psychosis were randomly assigned to either a 10-min, guided self-massage in the experimental group (EG) to enhance the sense of bodily boundaries or a control group (CG), which massaged a fabric ring. Effects on an implicit measure (jumping to conclusion bias; JTC) and an explicit measure (Brief State Paranoia Checklist; BSPC) of delusion processes were assessed. The JTC measures the tendency to make a decision with little evidence available, and the BSPC explicitly measures the approval of paranoid beliefs.

RESULTS

Patients in the EG showed a lower JTC (M = 4.11 draws before decision) than the CG (M = 2.43; Cohen's d = 0.64). No significant difference in the BSPC was observed.

DISCUSSION/CONCLUSION

Our results indicate that enhancing the sense of body boundaries through a self-massage can reduce an implicit bias associated with delusional ideation and correspondingly support the idea that disembodiment might be a relevant factor in the formation of psychotic symptoms.

Bodily Self-Disturbances in Schizophrenia: A Comparative Study of South Korea and the USA

BACKGROUND

Bodily self-disturbances are highly salient to the phenomenology of schizophrenia (SZ) but difficult to quantify owing to the subjective nature of these experiences that challenge verbal descriptions. The Benson et al. [PsyCh J. 2019 Mar;8(1):110-21] Body Disturbances Inventory (B-BODI) provides visual aids to help participants access the frequency, distressfulness, and vividness of subjective self-experiences with good reliability and validity in North American samples. However, the concept of the self and, accordingly, the conceptualization of self-disorders are influenced by culture. Therefore, we examined self-disturbances in individuals with SZ and control (CO) participants in 2 distinct cultures.

METHODS

B-BODI was administered to South Korean and North American participants, with and without SZ. Severity of symptoms in diagnosed individuals with SZ and schizotypy in CO was assessed. We also assessed perceived social isolation and mood in all participants.

RESULTS

Endorsement and frequency of bodily self-disturbances in SZ were similar in both cultures. In contrast, there were significant cultural differences in the degree of distress and vividness of self-disturbances. Bodily self-disturbances were experienced as more vivid and distressing to Americans than Koreans, regardless of diagnosis. For both cultures, B-BODI scores were associated with positive, but not negative, symptoms in SZ. For CO, elevated schizotypy was associated with B-BODI scores. Mood and loneliness were not associated with B-BODI scores.

CONCLUSION

SZ reported overall increased levels of bodily self-disturbances compared with CO, regardless of culture. However, there were cultural differences in one's emotional reaction to these experiences. Americans were more distressed by self-disturbances and experienced them more vividly than Koreans. These findings suggest that Americans may be less accepting of anomalous bodily self-experiences relative to Koreans. Last, B-BODI appears to be a useful tool for future cross-cultural studies of SZ phenomenology.

Disrupted Sense of Agency as a State Marker of First-Episode Schizophrenia: A Large-Scale Follow-Up Study

Background: Schizophrenia is often characterized by a general disruption of self-processing and self-demarcation. Previous studies have shown that self-monitoring and sense of agency (SoA, i.e., the ability to recognize one's own actions correctly) are altered in schizophrenia patients. However, research findings are inconclusive in regards to how SoA alterations are linked to clinical symptoms and their severity, or cognitive factors. Methods: In a longitudinal study, we examined 161 first-episode schizophrenia patients and 154 controls with a continuous-report SoA task and a control task testing general cognitive/sensorimotor processes. Clinical symptoms were assessed with the Positive and Negative Syndrome Scale (PANSS). Results: In comparison to controls, patients performed worse in terms of recognition of self-produced movements even when controlling for confounding factors. Patients' SoA score correlated with the severity of PANSS-derived "Disorganized" symptoms and with a priori defined symptoms related to self-disturbances. In the follow-up, the changes in the two subscales were significantly associated with the change in SoA performance. Conclusion: We corroborated previous findings of altered SoA already in the early stage of schizophrenia. Decreased ability to recognize self-produced actions was associated with the severity of symptoms in two complementary domains: self-disturbances and disorganization. While the involvement of the former might indicate impairment in self-monitoring, the latter suggests the role of higher cognitive processes such as information updating or cognitive flexibility. The SoA alterations in schizophrenia are associated, at least partially, with the intensity of respective symptoms in a state-dependent manner.

Schizotypal traits are not related to multisensory integration or audiovisual speech perception

Multisensory integration, the binding of sensory information from different sensory modalities, may contribute to perceptual symptomatology in schizophrenia, including hallucinations and aberrant speech perception. Differences in multisensory integration and temporal processing, an important component of multisensory integration, are consistently found in schizophrenia. Evidence is emerging that these differences extend across the schizophrenia spectrum, including individuals in the general population with higher schizotypal traits. In the current study, we investigated the relationship between schizotypal traits and perceptual functioning, using audiovisual speech-in-noise, McGurk, and ternary synchrony judgment tasks. We measured schizotypal traits using the Schizotypal Personality Questionnaire (SPQ), hypothesizing that higher scores on Unusual Perceptual Experiences and Odd Speech subscales would be associated with decreased multisensory integration, increased susceptibility to distracting auditory speech, and less precise temporal processing. Surprisingly, these measures were not associated with the predicted subscales, suggesting that these perceptual differences may not be present across the schizophrenia spectrum.

Influence of arousal on intentional binding: Impaired action binding, intact outcome binding

Emotional states have been indicated to affect intentional binding, resulting in an increase or decrease as a function of valence and arousal. Sexual arousal is a complex emotional state proven to impair attentional and perceptual processes, and is therefore highly relevant to feeling in control over one’s actions. We suggest that sexual arousal affects intentional binding in the same way as highly negative arousing states such as fear and anger. Ninety participants performed the intentional binding task before and after watching an either sexually arousing or emotionally neutral film clip. Analyses were conducted for the subcomponents action and outcome binding separately including the change in arousal before and after the emotion induction as a continuous measure. Results showed an interactive effect for time of measurement (before and after emotion induction) and arousal change on action binding: a decrease in action binding was noted in participants who reported to be more aroused and an increase in action binding was observed for participants who reported to be less aroused. Results emphasize that alterations in action binding are likely to reflect the deficits in the dopaminergic system involved in action execution. An impaired feeling of control in aroused states may play a crucial role for the underlying psychological mechanisms of impulsive violent behavior.

Embodied Predictions, Agency, and Psychosis

Psychotic symptoms, i.e., hallucinations and delusions, involve gross departures from conscious apprehension of consensual reality; respectively, perceiving and believing things that, according to same culture peers, do not obtain. In schizophrenia, those experiences are often related to abnormal sense of control over one's own actions, often expressed as a distorted sense of agency (i.e., passivity symptoms). Cognitive and computational neuroscience have furnished an account of these experiences and beliefs in terms of the brain's generative model of the world, which underwrites inferences to the best explanation of current and future states, in order to behave adaptively. Inference then involves a reliability-based trade off of predictions and prediction errors, and psychotic symptoms may arise as departures from this inference process, either an over- or under-weighting of priors relative to prediction errors. Surprisingly, there is empirical evidence in favor of both positions. Relatedly, there is evidence for both an enhanced and a diminished sense of agency in schizophrenia. How can this be? We argue that there is more than one generative model in the brain, and that ego- and allo-centric models operate in tandem. In brief, ego-centric models implement corollary discharge signals that cancel out the effects of self-generated actions while allo-centric models compare several hypothesis regarding the causes of sensory inputs (including the self among the potential causes). The two parallel hierarchies give rise to different levels of agency, with ego-centric models subserving "feelings of agency" and allo-centric predictions giving rise to "judgements of agency." Those two components are weighted according to their reliability and combined, generating a higher-level "sense of agency." We suggest that in schizophrenia a failure of corollary discharges to suppress self-generated inputs results in the absence of a "feeling of agency" and in a compensatory enhancement of allo-centric priors, which might underlie hallucinations, delusions of control but also, under certain circumstances, the enhancement of "judgments of agency." We discuss the consequences of such a model, and potential courses of action that could lead to its falsification.

Schizotypy and individual differences in peripersonal space plasticity

The space surrounding our body, defined as peripersonal space (PPS), is dynamically shaped by our motor experiences. For instance, PPS extends after using a tool to reach far objects. Several studies have demonstrated how PPS size varies across people, depending on different individual characteristics, including schizotypy. Coherently, narrower PPS boundaries have been reported among high schizotypal individuals and schizophrenia patients. However, little is known about the relationship between PPS plasticity and personality traits like schizotypy. To this purpose, the present study has investigated the individual PPS plasticity, after two different motor trainings, along the schizotypal continuum. Specifically, PPS plasticity was tested after using a tool (Experiment 1) and after the mere observation of another person using the same tool (Experiment 2). Indeed, previous evidence has shown that tool-use observation influences visual distance judgments, extending the representation of PPS. To date, however, there is no study investigating whether observation of tools action could also affect multisensory PPS tasks. Experiment 1 has shown that PPS boundaries extended after using the tool; on the other hand, Experiment 2 has revealed the absence of PPS expansion. Moreover, greater PPS expansion emerged in the relatively-low schizotypal group than in the relatively-high one, regardless of the type of motor training performed. The absence of PPS modulation after the observation task is discussed in relation to recent findings showing that intentional action and/or the goal of the action represent potentially crucial elements to trigger PPS plasticity. Finally, these new results extend previous evidence underlining a potential general functional alteration of PPS with the increase of schizotypal level.

Interpersonal Violence and Psychotic-Like Experiences: The Mediation of Ideas of Reference, Childhood Memories, and Dissociation

Previous studies have demonstrated the relationship between the accumulation of situations involving interpersonal violence (IV) and psychotic-like experiences. This study explored whether IV is related to aberrant salience (AS), using a sequential mediation model that included memories of relationship with parents (submission, devaluation, and threat; Early Life Experiences Scale (ELES)), ideas of reference (IR), and dissociative symptoms (absorption and depersonalization), and whether the patient/nonpatient condition moderated this effect. The sample was made of 401 participants (including 43 patients with psychotic disorders) aged 18 to 71 years (Mage = 30.43; SD = 11.19). Analysis of a serial multiple mediator model revealed that IR, ELES, absorption, and depersonalization fully mediated the effect of IV on AS, explaining 39% of the variance, regardless of the patient/nonpatient condition. The indirect paths, which place IR and dissociation (especially absorption, the variable to which the IR and ELES lead) in a primordial position for being related to AS, are discussed. This continuum model could be useful for understanding processes related to the onset of psychosis unmoderated by the patient/nonpatient condition.

Impaired action self-monitoring and cognitive confidence among ultra-high risk for psychosis and first-episode psychosis patients

Background

Self-monitoring biases and overconfidence in incorrect judgments have been suggested as playing a role in schizophrenia spectrum disorders. Little is known about whether self-monitoring biases may contribute to early risk factors for psychosis. In this study, action self-monitoring (i.e., discrimination between imagined and performed actions) was investigated, along with confidence in judgments among ultra-high risk (UHR) for psychosis individuals and first-episode psychosis (FEP) patients.

Methods

Thirty-six UHR for psychosis individuals, 25 FEP patients and 33 healthy controls (CON) participated in the study. Participants were assessed with the Action memory task. Simple actions were presented to participants verbally or non-verbally. Some actions were required to be physically performed and others were imagined. Participants were asked whether the action was presented verbally or non-verbally (action presentation type discrimination), and whether the action was performed or imagined (self-monitoring). Confidence self-ratings related to self-monitoring responses were obtained.

Results

The analysis of self-monitoring revealed that both UHR and FEP groups misattributed imagined actions as being performed (i.e., self-monitoring errors) significantly more often than the CON group. There were no differences regarding performed actions as being imagined. UHR and FEP groups made their false responses with higher confidence in their judgments than the CON group. There were no group differences regarding discrimination between the types of actions presented (verbal vs non-verbal).

Conclusions

A specific type of self-monitoring bias (i.e., misattributing imagined actions with performed actions), accompanied by high confidence in this judgment, may be a risk factor for the subsequent development of a psychotic disorder.

Self-disorders in Early Stages of the Schizophrenia Spectrum

The pathogenic nucleus of schizophrenia has varied according to the different eras and influences of distinguished clinical researchers. Self-disorders have also been recognised to be at the heart of this disorder, although they have seldom been studied due to their subjective nature. Recently, due to the growing interest in the study of the early stages of schizophrenia, the study of self-disorders has been resumed. The self-disorders in schizophrenia model, developed by Sass and Parnas, proposes that in this disorder the person suffers loss of the first-person perspective and experiences hyperreflexibility, diminished self-affection and disturbance of the field of awareness. Therefore, the person experiences feelings of strangeness about him/herself, difficulty in understanding the common sense of things and difficulty interacting with his/her environment. Based on this model, self-disorder evaluation instruments have been developed and empirical studies have been conducted to evaluate people at risk of developing a schizophrenia spectrum disorder. These studies show that self-disorders are found in prepsychotic stages and that their manifestation may predict the transition to schizophrenia spectrum disorders. These results have important clinical implications as they enable people in the early stages of the disorder to be identified and create the opportunity to apply early therapeutic interventions.

Disrupted Corollary Discharge in Schizophrenia: Evidence From the Oculomotor System

Corollary discharge (CD) signals are motor-related signals that exert an influence on sensory processing. They allow mobile organisms to predict the sensory consequences of their imminent actions. Among the many functions of CD is to provide a means by which we can distinguish sensory experiences caused by our own actions from those with external causes. In this way, they contribute to a subjective sense of agency. A disruption in the sense of agency is central to many of the clinical symptoms of schizophrenia, and abnormalities in CD signaling have been theorized to underpin particularly those agency-related psychotic symptoms of the illness. Characterizing abnormal CD associated with eye movements in schizophrenia and their resulting influence on visual processing and subsequent action plans may have advantages over other sensory and motor systems. That is because the most robust psychophysiological and neurophysiological data regarding the dynamics and influence of CD as well as the neural circuitry implicated in CD generation and transmission comes from the study of eye movements in humans and nonhuman primates. We review studies of oculomotor CD signaling in the schizophrenia spectrum and possible neurobiological correlates of CD disturbances. We conclude by speculating on the ways in which oculomotor CD dysfunction, specifically, may invoke specific experiences, clinical symptoms, and cognitive impairments. These speculations lay the groundwork for empirical study, and we conclude by outlining potentially fruitful research directions.

Anomalous self-experiences are strongly associated with negative symptoms in a clinical high-risk for psychosis sample

OBJECTIVE

Anomalous self-experiences (ASE) are considered as central features of the schizophrenia spectrum disorders and prodromal schizophrenia. We investigated total and single-item prevalence of these phenomena in a clinical high-risk (CHR) for psychosis sample, and associations with conventional psychosis-risk symptoms, present and childhood global/psychosocial functioning, and childhood trauma.

METHODS

The sample (n = 38) included 31 CHR, according to ultra-high risk or cognitive basic symptoms (COGDIS) criteria, and seven with non-progressive attenuated positive symptoms. Psychopathological evaluations included the Examination of Anomalous Self-Experience (EASE), Structured Clinical Interview for Prodromal Syndromes (SIPS), Schizophrenia Proneness Instrument - Adult (SPI-A) (only the COGDIS-criteria), a diagnostic interview (SCID-I), Global Assessment of Functioning - Split version (S-GAF), Premorbid Adjustment Scale (PAS) and Childhood Trauma Questionnaire (CTQ).

RESULTS

The mean total EASE score was in line with reports from other CHR samples, and was particularly enhanced in schizotypal personality disorder and in subjects fulfilling COGDIS-criteria. The four most frequent EASE-items were present in two-thirds or more of the participants. EASE total was significantly associated with negative and disorganization symptoms. A multiple regression analysis revealed that the level of negative symptoms explained most of the variance in EASE total.

CONCLUSIONS

These results corroborates other findings that anomalous self-experiences are frequent and important features in CHR conditions and in the schizophrenia spectrum. The strong associations with negative symptoms and cognitive disturbances (COGDIS) should be investigated in longitudinal studies to address causality, psychopathological pathways and schizophrenia spectrum specificity. The weaker correlation between EASE total and positive symptoms may partly be related to a restricted range of positive symptoms.

Autism and psychosis as diametrical disorders of embodiment

Humans have evolved an elaborate system of self-consciousness, self-identity, self-agency, and self-embodiment that is grounded in specific neurological structures including an expanded insula. Instantiation of the bodily self has been most-extensively studied via the 'rubber hand illusion', whereby parallel stimulation of a hidden true hand, and a viewed false hand, leads to the felt belief that the false hand is one's own. Autism and schizophrenia have both long been regarded as conditions centrally involving altered development of the self, but they have yet to be compared directly with regard to the self and embodiment. Here, we synthesize the embodied cognition literature for these and related conditions, and describe evidence that these two sets of disorders exhibit opposite susceptibilities from typical individuals to the rubber hand illusion: reduced on the autism spectrum and increased in schizophrenia and other psychotic-affective conditions. Moreover, the opposite illusion effects are mediated by a consilient set of associated phenomena, including empathy, interoception, anorexia risk and phenotypes, and patterns of genetic correlation. Taken together, these findings: (i) support the diametric model of autism and psychotic-affective disorders, (ii) implicate the adaptive human system of self-embodiment, and its neural bases, in neurodevelopmental disorders, and suggest new therapies and (iii) experimentally ground Bayesian predictive coding models with regard to autism compared with psychosis. Lay summary: Humans have evolved a highly developed sense of self and perception of one's own body. The 'rubber hand illusion' can be used to test individual variation in sense of self, relative to connection with others. We show that this illusion is reduced in autism spectrum disorders, and increased in psychotic and mood disorders. These findings have important implications for understanding and treatment of mental disorders.

Increased plasticity of bodily self-experience in individuals who may carry latent liability for schizophrenia

Self-disturbances such as altered perception of one's own body boundary are central to the lived-in experience of schizophrenia. Bodily self-disturbances are also prevalent in healthy individuals who may carry latent liability for schizophrenia. Much of the research on self-disturbances rely on clinical interviews but these experiences are often difficult to verbalize, conceptualize and quantify. Furthermore, experimental evidence for plasticity of bodily self-experience in the schizophrenia-spectrum is scarce. We sought to quantify body boundary experience in healthy young adults who might be at an increased risk for schizophrenia with a multisensory paradigm known as the Pinocchio Illusion (PI) task that engenders the feeling that one's nose is changing, and has previously been used to demonstrate increased plasticity of bodily self-boundary in schizophrenia. 62 college students participated in the PI task that assessed bodily self-disturbances, and a tactile discrimination task. We administered the Prodromal Questionnaire Brief (PQ-B) and the Schizotypal Personality Questionnaire (SPQ) to assess latent liability for schizophrenia. We found that PI was enhanced in individuals with elevated PQ-B scores but their tactile sensitivity was intact. PI was associated with the positive syndrome of schizotypy, but not with negative or disorganized factors. Increased PQ-B and SPQ scores were associated with loneliness. To conclude, these results highlight the importance of bodily self-disturbances in the broader context of the schizophrenia spectrum.

Bodily self-disturbance in schizophrenia-spectrum populations: Introducing the Benson et al. Body Disturbances Inventory (B-BODI)

Anomalous or weakened sense of self was central to early theories of schizophrenia. Recent studies have also documented disturbances in body ownership and increased susceptibility for dissociative experiences, such as the out-of-body experience in individuals with schizophrenia, but further research is necessary to clarify components of bodily self-disturbances in the schizophrenia spectrum, and the stability of these experiences over time. With respect to methodology, self-disturbances research in schizophrenia tends to rely exclusively on verbal self-report questionnaires and interviews. Given that individuals with schizophrenia suffer from language and communication difficulties, verbal self-report measures may be insufficient. To bridge this gap, we have developed a new picture-based instrument, the Benson et al. Body Disturbances Inventory (B-BODI), designed to quantify bodily self-disturbances with respect to the frequency and vividness of these experiences, as well as the degree of distress associated with them. Drawings that depicted different aspects of aberrant bodily self-experiences were presented with accompanying captions. Participants were asked to indicate the frequency, vividness, and distressfulness of the experience captured by the picture using a 5-point scale. Individuals with schizophrenia, older healthy controls, and college students participated in two alternative versions of the B-BODI. Participants were also asked to complete a battery of established questionnaires that probed psychosis proneness and a range of self, body, and perceptual aberrations. The results suggest that the B-BODI is a useful tool that accurately captures bodily self-disturbances and has the potential to predict psychosis risk in healthy young individuals. Furthermore, anomalous self-disturbances seem to be relatively stable across time in individuals with chronic schizophrenia.

Reframing schizophrenia and autism as bodily self-consciousness disorders leading to a deficit of theory of mind and empathy with social communication impairments

Prior observations and studies suggest self-consciousness disorders in schizophrenia and Autism Spectrum Disorder (ASD), two neurodevelopmental disorders sharing social communication impairments. First, the relationships between schizophrenia and autism are explored regarding social communication impairments. Then, self-consciousness disorders in schizophrenia and autism are described and discussed in relation with impairments of body self leading to impairments of self-other differentiation, a deficit of theory of mind and empathy, and their consequences on social communication. Also, neurological dysfunction involved possibly in self-consciousness disorders in schizophrenia and autism is presented. In conclusion, a new model is proposed integrating results of studies presented here and stating the existence of bodily self-consciousness disorders in schizophrenia and autism associated with altered/absent intermodal sensory integration (especially visual-kinesthetic-tactile integration). This would result in problems of self-other differentiation, leading in turn to a deficit of theory of mind and empathy as well as social communication impairments. This model opens new perspectives to understand better self-consciousness disorders and social communication impairments in schizophrenia and ASD and to develop therapeutic strategies.

Mediating role of aberrant salience and self-disturbances for the relationship between childhood trauma and psychotic-like experiences in the general population

INTRODUCTION

The relationship between childhood trauma and the risk of psychosis is well established. However, the mechanisms of the relationship are still unknown. We investigated whether two factors involved in the risk of psychosis - self-disturbances and aberrant salience - mediate the relationship between childhood trauma and psychotic-like experiences in the general population.

METHODS

We tested parallel mediation models which assume that the relationship between childhood trauma (Childhood Trauma Questionnaire, the CTQ) and psychotic-like experiences (Prodromal questionnaire, PQ-16) is mediated by both self-disturbances and aberrant salience (Aberrant Salience Inventory, the ASI) in a general population sample (N = 649). Separate parallel mediation models were calculated for cumulative childhood trauma, exposure to abusive behaviors (emotional, physical and sexual abuse) and neglect (emotional and physical neglect) controlling for gender.

RESULTS

Childhood traumatic life events predicted psychotic-like experiences. Childhood trauma was also related to self-disturbances and aberrant salience. Self-disturbances and aberrant salience were related to psychotic-like experiences. Models of mediation for the relationship between cumulative childhood trauma and neglect and psychotic-like experiences revealed an indirect-only mediation by self-disturbances and aberrant salience. The model for childhood abuse suggested a complementary mediation and was affected by gender.

CONCLUSIONS

Our results provide tentative evidence that self-disturbances and aberrant salience are important factors in the translation of childhood trauma into the risk of psychosis in the general population. Causal relationships could not be inferred from this cross-sectional data. Hence, longitudinal studies on a clinical sample are warranted.

Dopamine and sense of agency: Determinants in personality and substance use

Sense of agency refers to the feeling of control over one's own actions. The strength of this sense varies inter-individually. This means that people differ in their perception concerning the intensity of their intentions and actions. The current study aims to determine the factors influencing this sense of agency on a personality level. Furthermore, it gives insight into the correlative relation between the strength of the sense of agency and substance use. The study involved 210 participants who were tested for the experiment (intentional binding paradigm for sense of agency, hand paradigm for intentionality bias, questionnaires FAD-Plus, NI-20, substance use). Significant determinants in personality were narcissism (vulnerable subtype) and substance use (consumption in general beyond cannabis, and particularly for the substances cannabis, ecstasy, and cocaine). Both personality types were associated with a weaker sense of agency compared to controls. For both results, alterations in the dopaminergic system need to be discussed. The present results confirm prior hypotheses that dopamine seems to play a crucial role in perception of agency. Possibly a higher accessibility of dopamine increases sense of agency (hyper-binding), whereas a lower accessibility of dopamine decreases sense of agency (hypo-binding). A second aim of the study was to see whether there is a connection between sense of agency and intentionality bias. The perception of intention in others differs widely; some people tend to see arbitrary or accidental actions as unintentional, and others quickly label actions as 'intentional' although the information is not distinct for a categorization. This cognitive error is called intentionality bias. Results could not confirm a relationship between the two constructs-one's own intention and judging intention in others. This may be due to a lack of connection between the two constructs or to methodological aspects. Further directions and limitations are discussed.

The Multiple Dimensions of Insight in Schizophrenia-Spectrum Disorders

The concept of insight is used to indicate the propensity of patients with schizophrenia and other severe mental disorders to recognize their illness and engage in treatment. Thus, insight may have notable consequences for the ill individual: Those who lack insight are at higher risk of nonadherence to treatments, negative clinical outcomes, and worse community functioning. Although insight is an intuitive concept, its essence remains difficult to capture. However, many rating scales are available to aid assessment, both for clinical and research purposes. Insight cannot be reduced to a symptom, a psychological mechanism, or a neuropsychological function. It is likely to have dynamic relationships with all these dimensions and with responses to personal events and contextual factors. In particular, social consequences of mental illness and explanatory models that are alternative to the medical model may fundamentally shape insight and treatment choice. Moreover, the cultural or individual stigmatization of mental illness may turn the acquisition of insight into a painful event and increase the risk of depression. Clinicians need to carefully evaluate and promote insight through a personalized approach to aid patient process of care and personal growth.