Psychotic Symptoms as a Continuum between Normality and Pathology

Abstract

It is possible that clinical phenomena associated with mental illness lie on a continuum with normality. Along these lines, several recent reports have studied the prevalence of hallucinations and other psychotic symptoms in the general population. A recent meta-analysis of risk factors to develop subclinical psychotic symptoms shows associations with male sex, migrant status, living in urban centres, developmental stage, psychoactive drug use, and child and adult social adversity, 1 all of which are risk factors for schizophrenia as well. This study also revealed that about 75% to 90% of psychotic experiences are transitory and disappear over time. The transient developmental expression of psychosis (psychosis proneness) may persist and become clinically relevant (impairment). This process depends on the degree of environmental risk to which the person is eventually exposed. Continuum Between Normality and PathologicalThe lifetime prevalence of schizophrenia is known to be about 1%. This paper reviews the presence of psychotic features in the nonclinical population. The results of a literature review suggest that delusional and hallucinatory experiences are more common in the general population than we may think, and that there could well be a symptomatic continuum between people who have and people who have not been diagnosed with indisputable psychotic disorders. In the nonclinical population, voices are mainly positive and nonthreatening. Conversely, in the psychiatric population, they tend to be frequent, intrusive, and distressing. We address the question of voices considered as various human experiences and describe the emergence of the nonclinical group of people who hear voices. We also review the pathophysiology of auditory hallucinations as an illustration of a neurophysiological anomaly, which is useful to understand psychosis or schizophrenia. The main obstacle in the category-specific thought is that it remains impossible to unmistakably demarcate the border around schizophrenia. It is evident that the creation of a boundary is always possible by using arbitrary criteria that improve interrater reliability but exclude a considerable number of people who share multiple common features with diagnosed people.Can J Psychiatry. 2009;54(3):140-151. Highlights· Psychotic symptoms can be considered as a dimension of general human experience. · Psychosis can be understood as one of many dimensions of schizophrenia. · Knowledge of a person's social, cultural, and developmental context is fundamental when evaluating psychotic symptoms.

Why we need more debate on whether psychotic symptoms lie on a continuum with normality

“…By finessing the pathological hallmarks of traditional psychotic phenomena, our research risks losing the essence of psychosis. If, as some have suggested (Stip & Letourneau, 2009), we need to look beyond old-fashioned psychotic symptoms for novel treatment targets, we need to ensure that our phenomenological skills have not atrophied to such an extent that we are unable to define and characterize these new entities.…”

“…Since around the mid-1980s it has gained a large number of adherents so that it is now becoming the accepted dogma. Although the theory can call upon a relatively large body of evidence in its support, drawn from phenomenological studies, epidemiology, developmental psychopathology and cognitive psychology (Johns & van Os, 2001 ;Freeman, 2007 ;Stip & Letourneau, 2009 ;van Os et al 2009), there is also work that suggests that viewing all psychotic phenomena as continua may lead us down a blind alley in understanding the nature of psychosis.…”

La schizophrénie dissociative existe-t-elle ?

“…Si la dissociation est bien à l'avant-plan des symptômes et que l'origine du trouble est traumatique, ne serait-il pas mieux de considérer que les symptômes psychotiques sont tout simplement une part de l'expérience de ces personnes, sans les considérer pathologiques en soi (Stip et Letourneau, 2009) ? En effet, de nombreuses études ont montré que les symptômes psychotiques, notamment les délires et les hallucinations, sont prévalents dans la population générale (Beck et Rector, 2003 ;Ohayon, 2000) et qu'ils sont associés à la sévérité et à la fréquence des traumatismes dans l'enfance (Shevlin et al, 2007 ;Shevlin et al, 2008).…”

“…Certains auteurs prônent déjà le traitement des différentes dimensions de la schizophrénie plutôt que le simple traitement des symptômes psychotiques (Stip et Letourneau, 2009 …”

14:15 Persistence of the Extended Psychosis Phenotype in Young People: Link Between Vulnerability and Clinical Need

“…The prevalence of subclinical psychotic symptoms and experiences in the general population is much higher than that of psychotic disorder, indicating that Introduction endorsing such experiences does not necessarily lead to need for care. Recent meta analyses have shown that subclinical psychotic experiences, such as hallucinatory experiences or delusional thinking, are reported by as many as 10 30% of the general population (Nuevo, Chatterji, Verdes, Naidoo, Arango & Ayuso Mateos, 2010;Stip & Letourneau, 2009). The dimensions underlying these symptoms have shown to be similar in both clinical and non clinical psychosis (the latter referring to schizotypy, the non clinical manifestation of psychosis at the level of personality structure) (Johns & van Os, 2001; Rossi & Daneluzzo, 2002;Vollema & Hoijtink, 2000).…”