Poor sleep quality predicts psychotic-like symptoms: an experience sampling study in young adults with schizotypal traits.

Psychotic-like experiences (PLEs) are unusual experiences such as perceptual abnormalities and delusional-like thoughts that resemble the symptoms of psychosis at the sub-clinical level. PLEs are associated with sleep complaints in healthy and clinical samples; however, evidence for day-to-day associations between poor sleep and subsequent PLEs under naturalistic conditions is scarce. We hypothesized that poor sleep quality would predict next days' PLEs, and vice versa, daytime PLEs would be associated with worse subsequent sleep quality. Seventy-three university students with moderate to high levels of positive schizotypy participated in an experience sampling study. Participants rated their sleep each morning, as well as PLEs and affective states during the day over 3 weeks. Multilevel regression models indicated that poor sleep quality predicted increased PLEs the following day. Poor sleep was linked to negative daytime mood that partially mediated the associations between sleep quality and next days' PLEs. Furthermore, PLEs were enhanced in the evening as compared to daytime reports. The prediction of poor sleep quality by previous days' PLEs was negligible. The results are consistent with the position that sleep-related interventions might reduce the risk of psychosis, especially in individuals that tend to experience psychotic-like phenomena and negative affect.

Simor P ，Báthori N ，Nagy T ，Polner B ... -  《-》

Schizotypy unfolding into the night? Schizotypal traits and daytime psychotic-like experiences predict negative and salient dreams.

Symptoms of insomnia and frequent nightmares are prevalent in psychotic disorders, and are associated with psychotic-like experiences (PLEs) in the non-clinical population. Whereas the role of impaired sleep in psychosis was extensively examined by longitudinal and interventional approaches, studies on the association between psychosis and dream quality are scarce, and mainly cross-sectional. We conducted a three-week long prospective study in a group of healthy adults (N = 55), assessed schizotypal traits, daily PLEs, and the emotional quality of dreams recalled in the morning (N = 490). We extracted the latent factors of schizotypal traits and dream emotions, and examined the predictive value of trait-and state-like variables on day-to-day reports of PLEs and dream quality. PLEs reported in the evening predicted emotionally more negative and salient dream reports the following morning. On the other hand, the quality of dreams were not predictive of PLEs reported later during the day. Schizotypal personality traits were differentially associated with dream quality: Introvertive Anhedonia, Cognitive Disorganization, and General-Disorganized schizotypy were linked to more negative dream valence, whereas Unusual Experiences were associated with more salient dreams. Our findings highlight the relevance of the multidimensional nature of schizotypal traits, the role of different facets of schizotypy in daytime and nocturnal mental experiences, and the day-to-day associations between PLEs and dream affect. GENERAL SCIENTIFIC SUMMARIES (GSS): The aim of the study was to examine the temporal associations between psychotic-like experiences and dream emotions, taking into account the trait factors of schizotypy. Psychotic-like experiences during the evening hours predicted reporting more negative and salient dreams the following morning, and schizotypal personality traits were differentially associated with the dimensions of dream emotions.

Báthori N ，Polner B ，Simor P 《-》

Schizotypy, psychotic-like experiences and distress: an interaction model.

Psychotic-like experiences (PLEs) have been found to exist on a continuum in both general and clinical populations. Such experiences may characterize normal and abnormal variations in personality, as well as prodromal or high risk states for the development of psychotic disorders. High risk paradigms tend to emphasize distress and impairment associated with PLEs, yet the extent to which individuals find PLEs to be distressing likely depends on moderating factors. In particular, individuals high in trait schizotypy may differ in their appraisal and reaction to PLEs. The current study examines the relationship between schizotypy, PLEs, and distress associated with PLEs in a college sample. Participants (N=355) completed the Schizotypal Personality Questionnaire - Brief Version (SPQ-B), which assesses schizotypal traits, and the Prodromal Questionnaire - Brief Version (PQ-B), which assesses both PLEs and associated distress. Schizotypy was found to significantly moderate the association between PLEs and subjective distress. Individuals high in trait schizotypy reported more PLEs, yet less distress associated with PLEs, relative to individuals low in trait schizotypy. Implications for high-risk state assessment are discussed.

Kline E ，Wilson C ，Ereshefsky S ，Nugent KL ，Pitts S ，Reeves G ，Schiffman J ... -  《-》

Patterns of cannabis use, psychotic-like experiences and personality styles in young cannabis users.

To examine the influence of personality traits on the relationship between cannabis use and psychotic like experiences (PLEs) in young adults. 499 lifetime cannabis users aged 18 to 25years completed an online survey assessing PLEs using the positive scale of the Community Assessment of Psychic Experiences (CAPE) and personality styles using the Brief Schizotypal Personality Questionnaire (SPQ-B) and the Substance Use Risk Profile Scale (SURPS), a measure of trait hopelessness, anxiety-sensitivity, impulsivity and sensation seeking. Cannabis use was assessed using items from the Youth Risk Behaviour Survey (YRBS) and a self-report measure of the lifetime level of cumulative cannabis use. Cannabis use as well as schizotypy and the four SURPS personality risk profiles were significantly associated with the frequency of PLEs in young cannabis users. The cumulative levels of lifetime cannabis exposure, trait schizotypy and hopelessness were the strongest predictors of PLEs in the multivariate analysis. Little evidence of a moderating effect of the personality risk profiles on the relationship between cannabis use and PLEs was found. Trait hopelessness was found to have a moderating effect on the relationship between the recency of cannabis use and the frequency of PLEs. The cumulative levels of lifetime cannabis exposure, trait schizotypy and hopelessness were associated with PLEs in young cannabis users. Individuals with high levels of trait hopelessness who use cannabis may be at higher risk of PLEs. Future research is required to increase understanding of the relationship between cannabis use and PLEs, using more complex moderation models containing personality traits along with other risk factors for PLEs.

Spriggens L ，Hides L 《-》

Temporal associations between sleep quality and paranoia across the paranoia continuum: An experience sampling study.

Kasanova Z ，Hajdúk M ，Thewissen V ，Myin-Germeys I ... -  《-》