A self-disorder, also called ipseity disturbance, is a psychological phenomenon of disruption or diminishing of a person's minimal self – the fundamental sense that one's experiences are truly one's own.
[3] Detecting self-disorders may also be useful for early intervention in psychosis, since they occur in the prodrome of schizophrenia prior to the emergence of psychotic symptoms.
[4][5] The concept resembles the basic symptoms of schizophrenia, but the term itself was introduced in the early 2000s together with the Examination of Anomalous Self-Experience (EASE) scale, which is used to measure the presence and severity of self-disorder.
[citation needed] In the schizophrenia spectrum disorders, the minimal self and the self-world structure are "constantly challenged, unstable, and oscillating," causing anomalous self-experiences known as self-disorders.
[7][9] Similar phenomena can occur in other conditions, such as bipolar disorder and depersonalization derealization disorder, but Sass's (2014) review of the literature comparing accounts of self-experience in various mental disorders shows that serious self-other confusion and "severe erosion of minimal self-experience" only occur in schizophrenia;[10] as an example of the latter, Sass cites the autobiographical account of Elyn Saks, who has schizophrenia, of her experience of "disorganization" in which she felt that thoughts, perceptions, sensations, and even the passage of time became incoherent, and that she had no longer "the solid center from which one experiences reality", which occurred when she was 7 or 8 years old.
The presence of self-disorders may have predictive power for whether those with an at risk mental state will develop psychosis;[16][17] the risk of suicidal ideation and suicide by people with schizophrenia, though depression would also be an important factor;[18] predicting initial social dysfunction in people with either schizophrenic or bipolar psychosis;[19] and whether a person will move to a schizophrenia spectrum diagnosis later.
[23] The presence of self-disorders may cause reduced person insight into their illness through the alteration of the basic structures of consciousness.
In their review, Parnas, et al. (2014) say, "The psychiatrist's acquaintance with the phenomenon of 'non-specific specificity' is, in our view, extremely important in the context of early diagnostic assessment, especially of people presenting with a vague, unelaborated picture of maladjustment, underperformance, chronic malaise and dysphoria, negative symptoms, or hypochondriac preoccupations."
[1] Another systematic review and meta-analysis from 2022 covering an aggregated sample of 810 patients found good evidence to support the existence of self-disorders as core clinical feature in schizophrenia spectrum disorders.
[28] Sass and Borda have studied the correlates of the dimensions of self-disorders, namely disturbed grip (perplexity, difficulty "getting" stuff most people can get), hyperreflexivity (where thoughts, feelings, sensations, and objects pop up uncontrollably in the field of awareness, as well dysfunctional reflecting on matters and the self), and diminished self-affection (where the person has difficulty being "affected" by aspects of the self, experiencing those aspects as if they existed in an outer space), and have proposed how both primary and secondary factors may arise from dysfunctions in perceptual organization and multisensory integration.
[29][30] In a 2013 review, Mishara, et al., criticized the concept of the minimal self as an explanation for self-disorder, saying that it is unfalsifiable, and that self-disorder arises primarily from difficulty integrating different aspects of the self as well as having difficulty distinguishing self and other, as proposed by Lysaker and Lysaker: Ichstörung or ego disorder, as they say, in schizophrenia arises from disturbed relationships, and not from the "solipsistic" concept of the self as proposed by Sass, Parnas, and others.
[6] Likewise, Kurt Schneider's first-rank symptoms, especially his concept of ego disturbances [de] as well as the so-called passivity phenomena may be considered as examples of self-disorders.
[24] In early 2000s, a group of researchers including Danish psychiatrist Josef Parnas sought to operationalize and revive the idea of schizophrenia as a disorder of the minimal self.
[6][2] The scale was based on phenomenological interviews with first-admission people with schizophrenia spectrum disorders, to enable empirical research of self-disorders.
[34] The creation of the EASE resulted in an uptick in research into the topic, and the first systematic review of the concept was published in The Lancet Psychiatry in 2021, finding good empirical support for self-disorders as a defining characteristic of schizophrenia spectrum disorders.