Self-perceived cognitive lapses and psychological well-being in schizotypy: Generalized and domain-specific associations.

A critical link between schizotypy and schizophrenia is impoverished cognitive functioning. In the majority of studies, though: (1) cognition is examined with standard neuropsychological tasks; and (2) high-schizotypal individuals are defined according to criteria applied in the respective study sample. Taking these considerations into account, the aims of the present study were to examine: (1) differences between four pre-defined, according to normative criteria, schizotypal (paranoid, negative, disorganized and cognitive-perceptual) and one control groups in self-perceived cognitive lapses; and (2) associations between schizotypal dimensions, self-perceived cognitive lapses and psychological well-being. Two hundred and sixty-one participants were administered the Schizotypal Personality Questionnaire, the Cognitive Failures Questionnaire (CFQ) and the Flourishing Scale, which assesses psychological well-being. Negative schizotypals reported higher scores in almost all CFQ measures compared with the control group (all p values < 0.01) along with poorer psychological well-being compared with the control and the cognitive-perceptual groups (both p values < 0.001). The disorganized group had higher scores in distractibility, blunders and total CFQ scores compared with the control group (all p values < 0.001). High psychological well-being was significantly associated with low negative schizotypy and CFQ blunders along with high cognitive-perceptual schizotypy (all p values < 0.05). To summarize, negative schizotypy is associated with a profile of "generalized" self-perceived cognitive lapses while disorganized schizotypy is characterized by self-perceived cognitive slips that have previously been shown to be mediated by a fronto-parietal network. Although psychological well-being is negatively associated with social-context specific cognitive failures and negative schizotypy, it is positively associated with cognitive-perceptual schizotypy.

The association of schizotypal traits with Prepulse Inhibition: a double approach exploration.

Introduction: According to the fully-dimensional approach, schizotypy is a personality trait present in the population in a continuous manner while the quasi-dimensional approach emphasises its extreme presentations. In this study we examined the relationship between sensorimotor gating, a core risk-index of the schizophrenia-spectrum, and four schizotypal factors in a dimensional-wise and a dichotomising-wise approach. Methods: Two-hundred and eighty-three participants were assessed with the Schizotypal Personality Questionnaire and were tested for Prepulse Inhibition (PPI). Associations between the schizotypal factors and startle measures were examined with stepwise regressions (dimensional-wise approach). Individuals in the lower 20% or the upper 20% for each schizotypal factor were identified and between-group comparisons were conducted (dichotomising-wise approach). Results: We found that with both approaches, only high paranoid or negative schizotypy were associated with reduced PPI. The low negative schizotypy group had prolonged onset and peak latencies, indicating that prolonged stimulus detection accompanies superior sensorimotor gating in this group. Conclusions: The findings suggest that although differentiating the effects of the various schizotypal factors is primary, the approach employed is secondary. The study also adds evidence in the literature supporting PPI as a useful endophenotypic marker of the schizophrenia-spectrum and highlights the contribution of specific aspects of schizotypy.

Schizotypal traits, neurocognition, and paternal age in unaffected first degree relatives of patients with familial or sporadic schizophrenia.

Studies comparing cognitive processes between familial and sporadic schizophrenia have yielded inconsistent findings. In this study we examined differences in neurocognition and schizotypal traits in unaffected relatives of schizophrenia-spectrum patients with either the familial (multiplex) or the sporadic (simplex) subtype of the disorder, taking paternal age at birth into consideration. Simplex (n = 65; SR), multiplex (n = 35; MR) relatives and controls (n = 114) were compared on several cognitive functions and schizotypal traits; between-group differences were evaluated with and without including paternal age in the analyses. SR and MR had higher negative and paranoid traits compared with controls, but paternal age abolished the differences between the SR and control groups. When taking into account schizotypal traits and participants' age, controls outperformed MR in strategy formation and set-shifting and SR in psychomotor speed, set-shifting and executive working memory. After including paternal age in the analyses, controls outperformed MR in strategy formation, working memory and executive working memory and both groups in psychomotor speed and set-shifting. These findings suggest that multiplex relatives present with a "riskier" personality and cognitive profile when considering the effects of paternal age. Nevertheless, simplex relatives are impaired in fundamental cognitive processes, thus highlighting the detrimental effects of paternal age on neurocognition.

Schizotypy-Independent and Schizotypy-Modulated Cognitive Impairments in Unaffected First-Degree Relatives of Schizophrenia-spectrum Patients.

OBJECTIVE: The aim of the study was to compare the neurocognitive profile of unaffected first-degree relatives of schizophrenia patients with control individuals, controlling for different schizotypal traits. METHOD: One hundred and fifteen adult unaffected first-degree relatives of schizophrenia-spectrum patients and 122 controls were tested for schizotypy with the Schizotypal Personality Questionnaire. They also underwent a thorough neurocognitive assessment with a range of tasks covering several aspects of executive functioning. Between-group differences in cognition were examined first with multivariate analysis of variance and then with a series of multivariate analyses of covariance, including the schizotypal dimensions as covariates. RESULTS: The relatives had higher scores on all schizotypal dimensions compared with controls and poorer planning, problem solving, strategy formation and working memory, irrespective of schizotypal traits. They also scored lower in executive working memory and verbal fluency. The difference in executive working memory was sensitive to the effects of paranoid and negative schizotypy (both dimensions abolished the between-group difference) whereas the difference in verbal fluency was sensitive only to the effects of paranoid schizotypy. Neither cognitive-perceptual nor disorganized schizotypy accounted for any differences in neurocognition between relatives and the controls. CONCLUSIONS: Impairments in planning, problem solving, strategy formation and working memory are "core" impairments in the schizophrenia-spectrum, possibly due to high heritability effects in these functions. Impairments in executive working memory and verbal fluency are associated with paranoid and negative schizotypy, possibly due to alterations in a common fronto-temporo-parietal neural network.

Associations of differential schizotypal dimensions with executive working memory: A moderated-mediation analysis.

BACKGROUND: Increased schizotypal traits are observed in a percentage of the general population and in the schizophrenia-spectrum and have been associated with impairments in working memory. In this study we examined the effects of four schizotypal dimensions [Negative (NegS), Paranoid (ParS), Cognitive-Perceptual (CPS), Disorganized (DiS)] on executive working memory (EWM), as mediated by set-shifting, planning and control inhibition. We also examined whether these associations are moderated by family-history of psychosis. METHODS: Our sample consisted of 110 unaffected first-degree relatives of schizophrenia-spectrum patients and 120 control individuals. Schizotypy was assessed with the Schizotypal Personality Questionnaire. Participants were also tested with the Letter-Number Sequencing, Wisconsin Card Sorting, Stroop Color-Word and Stockings of Cambridge tasks. The effects of set-shifting, control inhibition and planning on the relationship between schizotypy and EWM were examined with mediation analyses. Moderated-mediation analyses examined potential moderating effects of group membership (unaffected relative/community participant). RESULTS: All mediators were significant in the relationship between NegS and EWM. The effects of ParS were mediated only by set-shifting and planning. Planning and control inhibition were the only significant mediators on the effects of CPS and DiS on EWM, respectively. The moderated-mediation analyses revealed that these findings apply only in the community group. CONCLUSIONS: We found that the effects of different schizotypal dimensions on EWM are mediated by other cognitive processes in individuals without personal/family history of psychosis. This is probably due to either more severe impairments in the cognitive processes of the relatives or restrictions in our sample and study-design.

Cognitive profiles of schizotypal dimensions in a community cohort: Common properties of differential manifestations.

INTRODUCTION: Studies assessing the effects of schizotypal dimensions (i.e., positive, negative, and disorganized) on cognitive functions have yielded mixed findings. In the present study, we administered an extensive battery of cognitive tasks to a community sample and defined the schizotypal dimensions according to a more analytical four-factor model, whereby positive schizotypy is further divided into cognitive-perceptual and paranoid. METHOD: Two hundred healthy community participants were assessed for schizotypy with the Schizotypal Personality Questionnaire; assessment of cognitive functions included set shifting, working memory, processing speed, verbal fluency, attention switching, planning/problem solving, strategy formation, and abstract reasoning. Associations between cognitive tasks and schizotypy were examined with hierarchical multiple linear regressions. We also divided our subjects into groups based on whether or not their scores in the negative, positive, and cognitive-perceptual factors fell in the upper 10% of the scores of a large community normative sample in Greece and examined between-group differences. RESULTS: Applying both dimensional and categorical approaches, we showed that (a) attention-switching impairment is a "core" deficit of both negative and paranoid schizotypy, (b) impaired working memory and set shifting are associated mainly with negative and to a lesser extent paranoid schizotypy, (c) paranoid schizotypy is associated with reduced performance in tasks requiring intact frontotemporal connectivity, and (d) cognitive-perceptual and disorganized schizotypy are not associated with any cognitive functions. CONCLUSIONS: Our findings further support the more analytical four-factor categorization of schizotypy and suggest that the discrepancies in the findings so far might be due to a more "generalized" definition of the schizotypal dimensions. They also add further in the early formulation of the profile of the high-schizotypal individuals seeking psychiatric help so that their overall management is directed towards a more targeted approach.

Psychometric properties of the Greek TCI-R and its clinical correlates: schizotypy and the self-regulation of affective and cognitive functioning.

Background. The revised Temperament and Character Inventory (TCI-R) measures Cloninger's psychobiological model of personality. The average effects of individual temperament and character traits have been associated with schizotypy and with impaired regulation of affect and cognition. We extended prior research by testing predictions about the association of specific multidimensional configurations of temperament and character traits on schizotypy, affect balance, and self-perceived cognitive functioning. Method. A well-educated sample of native Greeks (N = 483), completed a new Greek translation of the TCI-R, as well as the Schizotypal Personality Questionnaire (SPQ), the Positive/Negative Affect Schedule (PANAS) and the Cognitive Failures Questionnaire (CFQ). The factor structure of the TCI-R was examined with exploratory and confirmatory tests. Associations between reported measures were examined with correlational and regression analyses. Results. The TCI-R had good psychometric properties as expected from studies in other countries. As predicted, specific configurations of temperament and character were associated with schizotypy, negative affect balance, and cognitive lapses. The "Borderline/Explosive temperament" (high Novelty Seeking, high Harm Avoidance, low Reward Dependence), "Schizotypal/Disorganized character" (low Self-directedness, low Cooperativeness, high Self-transcendence), and "Low Ego Strength/Fragile" profile (high Harm Avoidance, low Persistence, low Self-Directedness) were each strongly associated with higher stereotypy, negative affect balance (low positive affect and high negative affect), and subjective cognitive lapses compared to their contrast groups. Discussion. Multidimensional TCI profiles are strongly related to individual differences in schizotypy and self-reported regulation of affect and cognition. The Greek translation of the TCI-R is psychometrically sound and useful for clinical assessment and research.

The validity of the Schizotypal Personality Questionnaire in a Greek sample: Tests of measurement invariance and latent mean differences.

BACKGROUND: The Schizotypal Personality Questionnaire (SPQ) is a widely used scale for measuring schizotypal characteristics modeled on DSM-III-R criteria for schizotypal personality disorder (SPD). The aim of this study was to examine the factorial structure of the Greek SPQ, its factorial invariance across gender and different age groups and possible gender and age group differences at latent mean level. METHODS: Eight hundred sixty-five community participants completed the Greek version of the SPQ. RESULTS: With regard to the factorial structure of the original first-order model, the results showed that a seven-factor model (sub-scales "no close friends" with "constricted affect" and "ideas of reference" with "unusual perceptual experiences" were combined) was replicated adequately. Furthermore, the second-order "paranoid" model provided also adequate fit. With regard to the factorial invariance of the SPQ across gender and age, the analysis revealed that both, the first- and second-order models showed measurement invariance (configural, metric and structural) across gender and age groups (17-35 vs. 36-70). Latent mean differences across gender and age groups were also found. CONCLUSIONS: Based on these findings, we can conclude that the Greek version of the SPQ is a psychometrically sound instrument for measuring schizotypal characteristics and a useful screening tool for SPD across gender and age.