Psychometric detection of schizotypy: Perceptual aberration and physical anhedonia in relatives of schizophrenics.

Abstract

We administered scales of Perceptual Aberration (PERAB) and Physical Anhedonia (PHYSAN), traits that may be related to risk for schizophrenia, to 54 schizophrenics, 146 of their first-degree relatives (evaluated for schizophrenia-related disorders), and 178 normal subjects (screened for psychotic disorders in them or their relatives). For both scales, there was a significant effect of group membership. For the PERAB scale, the schizophrenics had higher scores than the normal subjects, who had higher scores than the relatives. For the PHYSAN scale, schizophrenics had higher scores than their relatives, who had higher scores than the normal subjects. Patterns of familial correlations also suggested that physical anhedonia, but not perceptual aberration, may be familial among schizophrenics and their relatives. The PHYSAN scale, but not the PERAB one, may be a useful indicator of liability for schizophrenia among the relatives of affected probands.

Stress-Induced Dopamine Release in Humans at Risk of Psychosis: a [11C]Raclopride PET Study

“…However, the genetic liability for schizophrenia is thought to be better indexed by negative than positive symptom schizotypy (Tsuang et al, 1991). For example, PhysAn scores are elevated in the relatives of schizophrenic patients while PerAb scores are not (Katsanis et al, 1990;Clementz et al, 1991) and lifetime risk of schizophrenia-spectrum disorders is higher in relatives of anhedonic schizophrenia probands than in nonanhedonic probands (Schurhoff et al, 2003). Negative, but not positive, symptoms are also elevated in schizophrenia families (Tsuang et al, 1991), and PhysAn is a major component of the stable familial set of traits referred to as 'schizotaxia', which is observed in a subset of relatives (Tsuang et al, 2002).…”

“…Healthy individuals with elevated scores on the PhysAn scale also show many attributes of a high-risk population: they have an increased incidence of the cognitive, behavioral, and social abnormalities associated with schizophrenia, including impaired attention (Jutai, 1989;Wilkins and Venables, 1992;Erlenmeyer-Kimling et al, 1993), reaction time crossover (Simons, 1982), abnormal P300 amplitude (Miller, 1986), skin conductance nonresponsiveness (Dawson and Nuechterlein, 1984), and poorer social competence (Garnet et al, 1993;Blanchard et al, 1998). Further, PhysAn scores may have a familial component as they are higher in schizophrenic patients and their relatives than controls (Katsanis et al, 1990;Clementz et al, 1991;Franke et al, 1993), and are higher in individuals with schizophrenia-related personality disorders who have a genetic loading of schizophrenia than in those without it (Thaker, 2000).…”

Associations Between Multiple Dimensions of Schizotypy and Sociodemographic Variables in a Nonpsychiatric Sample of Young Adults

“…Biological relatives of individuals with schizophrenia exhibit more schizotypal traits than those without a family history of the disorder, suggestive of a genetic relationship between schizotypy and schizophrenia (Clementz et al, 1991;Kendler et al, 1995;Silverman et al, 1993). Furthermore, subclinical attenuated psychotic experiences of individuals with schizotypy resemble the symptomatology of schizophrenia (Claridge et al, 1996;Kendler et al, 1995;Raine et al, 1994;Vollema and Van den Bosch, 1995).…”

Confirmation of a four-factor structure of the Schizotypal Personality Questionnaire among undergraduate students

“…The study of schizotypy is of increasing interest to schizophrenia researchers given evidence that schizotypy and schizotypal personality disorder (SPD) relate phenotypically (Catts et al, 2000;Kendler et al, 1994;Siever et al, 1993) and genetically (Clementz et al, 1991;Kendler et al, 1995, Silverman et al, 1993 to schizophrenia. Ongoing research on schizotypy in non-clinical samples will deepen the field's understanding of this complex personality construct as a vulnerability marker, as an aspect of some cases of the schizophrenia prodrome, and as an indicator that can enhance genetic studies.…”