Schizophrenia Research
January 1, 2014
Louis Sass
216 citations
The ipseity-disturbance or self-disorder hypothesis proposes that a disruption of minimal or core self-experience is central to schizophrenia. This paper reviews and refines that model, recommending research into what is distinctive about the schizophrenia spectrum, the internal structure of self-disturbance, and testable pathways for pathogenesis and therapy. Exploratory comparisons of self-anomalies in mania, psychotic depression, depersonalization disorder, and intense introspection found similarities—such as alienation of thoughts and bodily experiences, fading of self and world—but also key differences: outside schizophrenia, severe erosion of minimal self-experience or confusion of self and other was absent. These findings support and refine the model. Future work should treat self-experience as an independent variable to study its links with cognition, affect, expression, and neural functioning.
Consciousness and Cognition
June 1, 2013
Louis Sass, Elizabeth Pienkos, Barnaby Nelson et al.
144 citations
Anomalous self-experiences are central to schizophrenia and other psychiatric disorders. This analysis compared such experiences in schizophrenia-spectrum disorders, as cataloged in the EASE, with those described in severe depersonalization. Numerous affinities were found, showing that pure forms of diminished self-affection (depersonalization) can involve experiences resembling those of schizophrenia. However, important discrepancies emerged, suggesting that more automatic or deficiency-like factors—probably involving self/world or self/other confusion and erosion of first-person perspective—are more distinctive of schizophrenia-spectrum disorders.
World psychiatry : official journal of the World Psychiatric Association (WPA)
June 1, 2015
Louis Sass, Greg Byrom
94 citations
Phenomenological accounts of delusions, especially in schizophrenia, emphasize disturbances in minimal self-experience (ipseity) and hyperreflexivity, while neurocognitive models stress salience dysregulation and prediction error. This paper reviews major phenomenological perspectives from Jaspers, Matussek, and Conrad, noting consistencies with neurocognitive approaches but also reservations about homogenizing tendencies that treat all delusions as mistaken beliefs about objective facts. The authors suggest that current neurocognitive models emphasizing hypersalience—where banal stimuli feel strange—may be complemented by considering hyposalience, where strange experiences feel banal, possibly linked to default mode network activation. Hyposalience could foster a derealized 'anything goes' attitude conducive to delusion formation, differing from the hypersalience focus in existing theories.
Schizophrenia Research
December 1, 2015
Louis Sass, Juan P Borda
44 citations
Schizophrenia involves a core disturbance in the sense of self (disturbed ipseity), which can be traced to a primary disruption in how the brain integrates perceptions from different senses (perceptual dys-integration). This article describes secondary phenomenological alterations that arise either as downstream consequences of that primary disruption or as defensive compensations. These include heightened self-consciousness (hyperreflexivity), a diminished sense of self-presence, and a weakened grip on one's field of awareness. These secondary experiences vary greatly between individuals and over time, and they become more pronounced in adolescence due to developing prefrontal lobe capacities. This variability may explain much of the clinical diversity in schizophrenia while still pointing to a common underlying disturbance.
Consciousness and Cognition
September 1, 2013
Louis Sass, Elizabeth Pienkos, Barnaby Nelson
42 citations
Comparing anomalous self-experiences common in schizophrenia with those of normal individuals in an intensely introspective orientation reveals significant similarities but also important differences. Affinities include feelings of passivity, fading of self or world, and alienation from thoughts, feelings, or the lived-body. Differences involve confusion between self and world and severe dislocation or erosion of first-person perspective, qualities unique to schizophrenia. The comparison places putatively schizophrenic self-disorders in a broader context, evaluates hypotheses about core processes in schizophrenia, and orients investigation of pathogenetic pathways and psychotherapeutic interventions.
Psychopathology
January 1, 2017
Luís Madeira, Sergio Carmenates, Cristina Costa et al.
31 citations
People with panic disorder report anomalous self-experiences—disturbances in the sense of self—at levels comparable to those seen in schizophrenia, though the specific patterns differ. In a study of 47 panic disorder patients and 47 healthy controls, patients scored much higher on the Examination of Anomalous Self Experiences (average 17.94 vs. 1.00 in controls). These experiences included common forms of derealization and depersonalization, which may reflect defensive psychological processes rather than a fundamental disturbance of the minimal self. The findings support the idea that basic-self-disturbance is specific to schizophrenia, while panic disorder involves a different, less profound type of self-alteration that can resemble schizophrenia-like phenomena but requires careful differentiation.
Psychopathology
January 1, 2008
Barnaby Nelson, Louis Sass
24 citations
The relationship between substance use and psychosis is usually studied as a cause-and-effect question, but the subjective experiences of both are often overlooked. This paper compares the phenomenology of psychosis onset, based on Sass's four components (Unreality, Fragmentation, Mere Being, Apophany), with the experience of hallucinogenic intoxication as described by Huxley. The analysis finds significant parallels, including a breakdown of the sign-referent relationship and disconnection from the practical world. However, in psychosis this breakdown feels like alienation from self and world, while in hallucinogenic states it is experienced as mystical union and revelation. The authors suggest a shared factor—psychotic-like experience—and propose further research on other drugs like cannabis.
Schizophrenia Research
September 1, 2019
Luís Madeira, Elizabeth Pienkos, Teresa Filipe et al.
18 citations
People with first-episode psychosis often experience profound changes in how they perceive the world around them—including alterations in space, time, and other people—alongside disturbances in their sense of self. In a study comparing 24 outpatients with first-episode psychosis to 24 healthy controls, those with psychosis scored significantly higher on both the Examination of Anomalous World Experience (EAWE) and the Examination of Anomalous Self Experience (EASE). Scores on the two measures were strongly correlated, even after accounting for overlapping items. The types of world-experience anomalies varied widely among patients. These findings suggest that anomalous world experiences are a relevant feature of first-episode psychosis and may be linked to the self-disturbances thought to underlie schizophrenia spectrum disorders.
Early Intervention in Psychiatry
July 2, 2023
Marija Krcmar, Cassandra Wannan, Suzie Lavoie et al.
6 citations
Basic self-disturbance is a potential core vulnerability marker for schizophrenia spectrum disorders. The Self, Neuroscience and Psychosis (SNAP) study tests a neurophenomenological model of psychosis by examining clinical, neurocognitive, and neurophysiological variables in individuals at ultra-high risk (UHR) for psychosis. It includes 400 UHR individuals, 100 clinical controls without attenuated psychotic symptoms, and 50 healthy controls. Participants complete baseline assessments and electroencephalography; UHR participants are followed for 24 months with clinical assessments every 6 months. The protocol aims to develop a prediction model for persistence or worsening of UHR symptoms at 12 months and to determine how specific these disturbances are to attenuated psychotic symptoms.
Australasian psychiatry : bulletin of Royal Australian and New Zealand College of Psychiatrists
August 1, 2025
Vera A Barata, Suzie Lavoie, Łukasz Gawęda et al.
3 citations
Among 43 individuals at ultra-high risk for psychosis, those who later remitted had lower baseline levels of basic self-disturbance than those whose symptoms persisted or who transitioned to psychosis. Basic self-disturbance scores predicted worse clinical outcomes at 12 months. Source monitoring deficits were greater in first-episode psychosis patients than in those at ultra-high risk whose symptoms persisted or transitioned. The findings suggest that high levels of basic self-disturbance may serve as a predictor of poor prognosis in ultra-high risk patients.
The lancet. Psychiatry
March 1, 2026
Jasper Feyaerts, Pavan S Brar, Louis Sass et al.
1 citation
Psychiatric research has long sought to identify and treat people in the early stages of psychosis, but progress has been limited. This paper argues that combining dynamical systems theory with the phenomenological self-disturbance model of schizophrenia can improve understanding and prediction of psychosis. The integration specifies causal processes involving altered self-awareness and reality-awareness, whose dynamics can be modeled to anticipate the onset and recurrence of psychotic episodes. This approach may enable earlier, personalized therapeutic interventions. Empirical testing of the model requires intensive longitudinal studies and phenomenological assessment methods. The authors also discuss theoretical and methodological challenges to implementing their proposal.
Psychopathology
August 18, 2025
Evan J. Kyzar, George H Denfield, Jasper Feyaerts et al.
1 citation
Integrating methods from phenomenology can strengthen the application of dynamical systems theory (DST) in psychopathology research. Phenomenological psychopathology improves DST-based investigations by specifying core symptoms more precisely through a focus on subjective experiences and by deepening theoretical understanding of how symptoms evolve in severity over time. Using clinical high risk for psychosis as a test case, the article demonstrates the utility of combining phenomenologically informed theory and DST, examining the ipseity-disturbance model of psychosis development. The authors offer a vision for broader integration of DST and phenomenological research methods to better understand and predict psychiatric disorders and transitions in mental health states.
Frontiers in Psychiatry
January 1, 2025
Aleksandra Jeličić, Maja Drobnič Radobuljac, Louis Sass et al.
1 citation
People with autism spectrum disorder (ASD) and schizophrenia spectrum disorder (SSD) often show similar social difficulties, leading to misdiagnosis. This study used in-depth phenomenological interviews with 42 participants aged 15 to 26, all with at least average intelligence and no acute psychiatric symptoms, to compare their subjective experiences. The SSD group showed higher levels of minimal self-disorder, demarcation phenomena, paranoid anxiety, short-term memory disorder, and magical thinking. Both groups overlapped in obsessive thinking, attention problems, diminished presence in the world, social anxiety, and hyper-reflectivity. The findings suggest that a disorder of ipseity (the sense of self) is central to SSD, while a disorder of primary intersubjectivity is central to ASD.
January 18, 2024
Jasper Feyaerts, Barnaby Nelson, Louis Sass
1 citation
preprint
Phenomenological research on schizophrenia often views self-disorders as disturbances of the 'minimal self,' the most basic sense of self. This paper identifies challenges for that view, including problems with the minimal self being considered essential to conscious experience and the fact that some schizophrenia patients experience an exaggerated, not diminished, sense of self. The authors then explore an alternative 'transparency-view' of consciousness, which treats self-awareness as a transparent quality of experience rather than a separate entity. They argue this view can account for loss-of-self experiences, aligns with the concept of hyper-reflexivity (excessive self-awareness), and explains instances of increased selfhood. The paper suggests this alternative may offer advantages for research and clinical approaches.