Schizotypal Personality Disorder

Abstract

Early phenomenological descriptions of schizophrenia have acknowledged the existence of milder schizophrenia spectrum disorders characterized by the presence of attenuated symptoms typically present in chronic schizophrenia. The investigation of the schizophrenia spectrum disorders offers an opportunity to elucidate the pathophysiological mechanisms giving rise to schizophrenia. Differences and similarities between subjects with schizotypal personality disorder (SPD), the prototypical schizophrenia personality disorder, and chronic schizophrenia have been investigated with genetic, neurochemical, imaging, and pharmacological techniques. Patients with SPD and the more severely ill patients with chronic schizophrenia share cognitive, social, and attentional deficits hypothesized to result from common neurodevelopmentally based cortical temporal and prefrontal pathology. However, these deficits are milder in SPD patients due to their capacity to recruit other related brain regions to compensate for dysfunctional areas. Individuals with SPD are also less vulnerable to psychosis due to the presence of protective factors mitigating subcortical DA hyperactivity. Given the documented close relationship to other schizophrenic disorders, SPD will be included in the psychosis section of DSM-5 as a schizophrenia spectrum disorder as well as in the personality disorder section.

Cognitive Deficits in Psychotic Disorders: A Lifespan Perspective

“…However psychotic experiences occur on a spectrum. There is evidence that approximately 20% of individuals in the general population have subtle psychotic-like experiences (van Os et al 2009), while approximately 2–5% meet criteria for schizotypal personality disorder (Chemerinski et al 2013), a disorder characterized by magical thinking, ideas of reference, and perceptual aberrations that do not rise to the level of primary psychosis. In recognition of mental illness as continuous in nature, the NIMH put forth Research Domain Criteria to conceptualize and research aspects of psychopathology through a dimensional lens (Insel et al 2010).…”

Psychosis

“…These deficits are often accompanied by unusual perceptual experiences (illusions) and cognitive distortions (ideas of reference, suspiciousness or paranoia, odd beliefs, or magical thinking that are held without delusional conviction) similar to, but less severe than, those experienced by people with schizophrenia. As noted by Chemerinski and colleagues, 20 schizotypal disorder and schizophrenia feature cognitive, social, and attentional deficits based in neurodevelopmentally mediated temporal and prefrontal cortical pathology. These deficits are milder in people with schizotypal disorder than in those with schizophrenia, possibly as a result of preserved capacity in the schizotypal brain to recruit related brain regions and thereby compensate for dysfunctional areas.…”

Seven basic dimensions of personality pathology and their clinical consequences: Are all personalities equally harmful?

“…Its negligible clinical impact in our study was unexpected as schizotypal PD is definitely debilitating in other studies (Kwapil, Gross, Silvia, & Barrantes‐Vidal, ; McClure, Harvey, Bowie, Iacoviello, & Siever, ; Nakao et al ., ; Skodol et al ., ) and is deemed to border schizophrenia (Nelson, Seal, Pantelis, & Phillips, ). Nevertheless, its most pathological features, such as psychotic symptoms, are not uncommon in the general population (Johns & van Os, ) and their consequences are largely unknown (Chemerinski, Triebwasser, Roussos, & Siever, ; Soeteman et al ., ; Ullrich et al ., ). Persistence–Compulsivity, which measures ambitiousness, self‐demandingness, and overachievement, played a minor role in clinical severity, was irrelevant to functioning, and increased satisfaction (see Ullrich et al ., for similar results).…”