Georgina M. Gross

Positive and negative schizotypy are associated with prodromal and schizophrenia- spectrum symptoms

The present study examined the validity of psychometrically assessed positive and negative schizotypy in a study of 214 Spanish young adults using interview and questionnaire measures of impairment and psychopathology. Schizotypy provides a useful construct for understanding the etiology and development of schizophrenia and related disorders. Recent interview, laboratory, and experience sampling studies have supported the validity of psychometrically assessed positive and negative symptom dimensions. The present study expands on previous findings by examining the validity of these dimensions in a Spanish sample and employing a widely used interview measure of the schizophrenia prodrome. As hypothesized, the positive schizotypy dimension predicted CAARMS ultra high-risk or psychosis threshold status, and both dimensions uniquely predicted the presence of schizophrenia-spectrum personality disorders. Furthermore, positive schizotypy was associated with psychotic-like, paranoid, schizotypal, and mood symptoms, whereas negative schizotypy was associated with interview ratings of negative and schizoid symptoms. The schizotypy dimensions were also distinguished by their associations with self and other schemas. Positive schizotypy was associated with increased negative self and other schemas, whereas negative schizotypy was associated with decreased positive self and other schemas. The findings provide further construct validation of positive and negative schizotypy and support these dimensions as universal constructs.

Psychometric properties and validity of short forms of the Wisconsin Schizotypy Scales in two large samples

The Wisconsin Schizotypy Scales (WSS) have been widely used in the study of clinical and non-clinical samples. However, researchers often find the length of the scales prohibitive. The present study examined the reliability and validity of recently developed 15-item short forms of the Perceptual Aberration, Magical Ideation, Physical Anhedonia, and Revised Social Anhedonia Scales in two large samples of non-clinically ascertained young adults. The scales demonstrated good reliability and correlated highly with the original scales. The validity of the scales was assessed by comparing the association of the original and shortened WSS with interview measures of psychotic-like and schizophrenia-spectrum symptoms and impaired functioning, as well as with questionnaire measures of personality and social impairment. The associations of the shortened WSS with the interview and questionnaire measures were comparable in terms of statistical significance and effect size with the associations of the original scales. The present findings provide the first demonstration of the validity of the shortened WSS and support their use in the study of schizotypy.

Comparing the factor structure of the Wisconsin Schizotypy Scales and the Schizotypal Personality Questionnaire

Schizotypy is a multidimensional construct that captures the expression of schizophrenic symptoms and impairment from subclinical levels to full-blown psychosis. The present study examined the comparability of the factor structure of 2 leading psychometric measures of schizotypy: the Wisconsin Schizotypy Scales (WSS) and the Schizotypal Personality Questionnaire (SPQ). Both the SPQ and WSS purportedly capture the multidimensional structure of schizotypy; however, whether they are measuring comparable factors has not been empirically demonstrated. This study provided support for a 2-factor model with positive and negative factors underlying the WSS; however, contrary to previous findings, the best fit for the SPQ was for a 4-factor model using confirmatory factor analysis, and a 2-factor model using exploratory factor analysis. The WSS factors were relatively distinct, whereas those underlying the SPQ showed high overlap. The WSS positive and SPQ cognitive-perceptual factors appeared to tap comparable constructs. However, the WSS negative and SPQ interpersonal factors appeared to tap somewhat different constructs based on their correlation and their patterns of associations with other schizotypy dimensions and the Five-Factor Model-suggesting that the SPQ interpersonal factor may not adequately tap negative or deficit schizotypy. Although the SPQ offers the advantage over the WSS of having a disorganization factor, it is not clear that this SPQ factor is actually distinct from positive schizotypy. Existing measures should be used with caution and new measures based on a priori theories are necessary to further understand the factor structure of schizotypy.

The dimensional structure of short forms of the Wisconsin Schizotypy Scales

The Wisconsin Schizotypy Scales (WSS) are widely used for assessing schizotypy. Confirmatory factor analysis (CFA) indicates that a two-factor structure, positive and negative schizotypy, underlies these scales. Recently developed 15-item short forms of the WSS demonstrated good reliability and validity. This study examined the factor structure underlying the short-form WSS. Consistent with the original scales, CFA on three large samples (n=6137, 2171, and 2292, respectively) indicated that a two-factor model with positive and negative dimensions provided better fit than a generic schizotypy model for the short-form WSS. The short-form dimensions correlated highly with the original scale dimensions and displayed good stability across 10weeks. Preliminary construct validity was demonstrated through associations with interview and questionnaire measures of psychopathology, functioning, and personality comparable to those found with the original WSS. This is the first study examining the dimensional structure of the short WSS and the validity of these dimensions. The findings support the multidimensional nature of schizotypy and the appropriateness of dimensions derived from the short-form WSS.

For Whom the Mind Wanders, and When, Varies Across Laboratory and Daily-Life Settings

Undergraduates (N = 274) participated in a weeklong daily-life experience-sampling study of mind wandering after being assessed in the lab for executive-control abilities (working memory capacity; attention-restraint ability; attention-constraint ability; and propensity for task-unrelated thoughts, or TUTs) and personality traits. Eight times a day, electronic devices prompted subjects to report on their current thoughts and context. Working memory capacity and attention abilities predicted subjects’ TUT rates in the lab, but predicted the frequency of daily-life mind wandering only as a function of subjects’ momentary attempts to concentrate. This pattern replicates prior daily-life findings but conflicts with laboratory findings. Results for personality factors also revealed different associations in the lab and daily life: Only neuroticism predicted TUT rate in the lab, but only openness predicted mind-wandering rate in daily life (both predicted the content of daily-life mind wandering). Cognitive and personality factors also predicted dimensions of everyday thought other than mind wandering, such as subjective judgments of controllability of thought. Mind wandering in people’s daily environments and TUTs during controlled and artificial laboratory tasks have different correlates (and perhaps causes). Thus, mind-wandering theories based solely on lab phenomena may be incomplete.

Development and psychometric properties of the Multidimensional Schizotypy Scale: a new measure for assessing positive, negative, and disorganized schizotypy

This article reports on the development of a new self-report questionnaire measure of schizotypy - the Multidimensional Schizotypy Scale (MSS). Schizotypy offers a useful and unifying construct for understanding schizophrenia-spectrum psychopathology. Questionnaire measures have been widely used to assess schizotypy and have greatly informed our understanding of the construct. However, available measures suffer from a number of limitations, including lack of a clear conceptual framework, outdated wording, unclear factor structure, and psychometric shortcomings. The MSS is based on current conceptual models and taps positive, negative, and disorganized dimensions of schizotypy. The derivation sample included 6265 participants sampled from four universities and Amazon Mechanical Turk. A separate sample of 1000 participants from these sources was used to examine the psychometric properties of the final subscales. Scale development employed classical test theory, item response theory, and differential item function methods. The positive schizotypy and negative schizotypy subscales contain 26 items each, and the disorganized schizotypy subscale contains 25 items. The psychometric properties were almost identical in the derivation and validation samples. All three subscales demonstrated good to excellent reliability, high item-scale correlations, and good item and test curve characteristics. The MSS appears to provide a promising measure for assessing schizotypy.

The multidimensional schizotypy scale-brief: Scale development and psychometric properties

This article reports on the development and psychometric properties of a brief version of the Multidimensional Schizotypy Scale (MSS-B). The MSS-B contains 38 items that assess positive, negative, and disorganized schizotypy. The scale was derived from the full-length Multidimensional Schizotypy Scale, and the positive, negative, and disorganized subscales were designed to provide the same content coverage as the original subscales. Scale development involved a derivation sample (n = 6265) and a separate cross-validation sample (n = 1000), both drawn from four universities and Amazon Mechanical Turk. The MSS-B was derived using classical test theory, item response theory, and differential item functioning. The three subscales exhibited high internal-consistency reliability, good item- and model-fit, good test information functions, and expected patterns of intercorrelations and associations with neuroticism, sex, and race/ethnicity. This pattern of findings was almost identical between the derivation and cross-validation samples. Furthermore, the pattern of findings was closely comparable for MSS-B subscales and the full-length MSS subscales. The MSS-B appears to offer a promising brief measure for assessing schizotypy.

Anhedonia and Negative Symptom Schizotypy

Current conceptualizations of schizophrenia indicate that the underlying vulnerability for the disorder is expressed across a broad continuum of impairment referred to as schizotypy. Trait-like anhedonia has long been recognized as a central component of schizophrenia and schizotypy. Our understanding of the etiology, experience, and expression of anhedonia, however, has evolved in large part due to advances in social and emotion psychology regarding the nature of pleasure, advances in the neurosciences regarding the brain mechanisms underlying hedonic capacity and experience, and the integration of measures from clinical, social, and biological psychology. Current studies have differentiated deficits in anticipatory pleasure from deficits in consummatory pleasure. The study of anhedonia has also been enhanced by the use of experience sampling research methods that expand investigations from the laboratory and the clinic to real world environments. Anhedonia appears to be a core component of the negative or deficit symptom dimension of schizotypy and schizophrenia, whereas the positive or psychotic-like dimension appears to be characterized by affective dysregulation. Furthermore, schizotypic anhedonia is differentiated from conditions such as depression, which involve episodic anhedonia combined with elevated negative affect. The present chapter presents an overview of theoretical conceptualizations of anhedonia in schizotypy, reviews cross-sectional, longitudinal, and daily life research findings, and considers issues and directions for future study of the construct.

Validity of the Multidimensional Schizotypy Scale: Associations with schizotypal traits and normal personality.

The present study provided the first examination of the construct validity of the Multidimensional Schizotypy Scale (MSS) and the first assessment of its psychometric properties outside of its derivation samples. The MSS contains 77 items that assess positive, negative, and disorganized schizotypy. A large multisite sample of 1,430 participants completed the MSS and measures of schizotypal personality traits and the five-factor model of personality. The MSS subscales had good-to-excellent internal consistency reliability that showed no shrinkage relative to the MSS derivation samples. The psychometric properties and intercorrelations of the MSS subscales were closely consistent with the derivation findings. The MSS Positive Schizotypy subscale had a strong association with cognitive–perceptual schizotypal traits (large effect), positive associations with personality traits of neuroticism and openness to experience, and negative associations with agreeableness. The MSS Negative Schizotypy subscale had a strong association with interpersonal schizotypal traits (medium effect) and negative associations with personality traits of extraversion, openness, and agreeableness. The MSS Disorganized Schizotypy subscale had a strong association with disorganized schizotypal traits (medium effect), a positive association with neuroticism, and a negative association with conscientiousness. The findings were consistent with the a priori predictions and support the construct validity of the MSS.

Does deployment-related military sexual assault interact with combat exposure to predict posttraumatic stress disorder in female veterans?

The objective of the present research was to expand upon previous findings indicating that military sexual trauma interacts with combat exposure to predict posttraumatic stress disorder (PTSD) among female Iraq/Afghanistan-era veterans. In total, 330 female veterans completed self-report measures of combat experiences, military sexual assault (MSA) experiences, and PTSD symptoms as well as structured diagnostic interviews for PTSD. A significant strength of the present research was the use of PTSD diagnosis as an outcome measure. Consistent with previous research, both combat exposure and MSA were significant predictors of PTSD symptoms (linear regression) and PTSD diagnoses (logistic regression). Specifically, participants who experienced deployment-related MSA had approximately 6 times the odds of developing PTSD compared with those who had not experienced deployment-related MSA, over and above the effects of combat exposure. Contrary to expectations, the hypothesized interaction between MSA and combat exposure was not significant in any of the models. The low base rate of MSA may have limited power to find a significant interaction; however, these findings are also consistent with other recent studies that have failed to find support for the hypothesized interaction. Thus, whereas the majority of available evidence indicates that MSA increases risk for PTSD among veterans over and above the effects of combat, there is presently only limited support for the hypothesized MSA × Combat interaction. These findings highlight the continued need for prevention and treatment of MSA to improve veterans’ long-term mental health and well-being.