Speech Illusion, Perceived Social Standing and Self-Esteem in Psychosis Proneness: the Twinsscan China Study

Abstract

BACKGROUND: Psychosis proneness refers to psychotic events experienced at sub-threshold level, and can be regarded as representing one part of the continuum that extends from normal daily experiences to clinical symptoms. Poor social cognition and low self-esteem are identified predictors of schizophrenia and possibly psychosis proneness. In light of this, the current study aimed to verify the predictive power of self-esteem, perceived social standing and speech illusion on psychosis proneness in a Chinese population and to verify the relationship between the three. It was hypothesized that self-esteem mediates the effect of perceived social standing on psychosis proneness. METHODS: 100 Chinese participants aged 15 to 21 were recruited in Beijing and Hong Kong (52 males, Mean age = 18.92, SD = 2.05). All participants were healthy without existing significant medical condition or mental illnesses and underwent a procedure that included three self-report questionnaires and a computerized task. More specifically, the Community Assessment of Psychic Experiences (CAPE) was administered to measure the frequency and distress of positive, negative and depressive symptoms (psychosis proneness). The Rosenberg Self-Esteem Scale (RSES) was used to measure individual’s self-esteem. All 10 items were rated on a four-point scale in which a higher score reflected a higher global self-esteem. The Social Comparison Scale (SCS) measured relative social standing using a semantic differential methodology on 11 bipolar constructs. Finally, speech illusion was assessed by the White Noise Task (Galdos et al. (2011)). In this task sentences were embedded in white noise to compose three types of stimuli (i) noise, (ii) clearly audible sentence and (iii) barely audible sentences. Participants responded by indicating them as (1) positive, (2) negative, (3) neutral, (4) no speech, or (5) uncertain for each of the 75 recordings. RESULTS: Participants showed more negative and depressive psychotic symptoms than positive symptoms in general. Low self-esteem and low perceived social standing predicted higher psychosis proneness, more negative and depressive symptoms (self-esteem: all ps<0.001; perceived social standing: ps=0.027, 0.005, 0.001). Further, the effect of perceived social standing on psychosis proneness was completely mediated through self-esteem (p<0.001). Nevertheless, no significant correlation was found between speech illusion with other variables. DISCUSSION: The results suggest that low self-esteem and perceived social standing are possible risk indicators of psychosis. The complete mediating effect of self-esteem on the association between perceived social standing and psychosis proneness suggests that poor self-judgments based on internalized social information may intensify one’s vulnerability in developing psychosis. Self-esteem and perceived social standing may add to the list of cognitive markers of psychosis identified so that at-risk individuals could be identified more effectively in the pre-morbid stage.