Schizotypal traits and cognitive function in healthy adults.
ABSTRACT Growing evidence has shown that psychometrically identified schizotypes among student populations have subtle cognitive impairments in several domains such as attention, working memory and executive function, but the possible association between psychometric schizotypy in adult populations and cognitive function has not been well documented. Here we examined the association between schizotypal traits as assessed by the Schizotypal Personality Questionnaire (SPQ) and cognitive function including memory, attention, executive function, and general intelligence in 124 healthy adults. Cognitive functioning was assessed with the Wechsler Memory Scale-Revised (WMS-R), the Wechsler Adult Intelligence Scale-Revised (WAIS-R), and the Wisconsin Card Sorting Test (WCST). SPQ scores showed a significant inverse correlation with verbal IQ and the information, comprehension and similarities subtests. No correlation was found between SPQ scores and memory, attention, performance IQ, or executive functioning. These results indicate that schizotypal traits in healthy adults are associated with verbal IQ decrements, suggesting that schizotypal traits themselves, even at a non-clinical level, may play unfavorable roles in cognitive functioning, which is in line with the viewpoint that schizotypy is on a continuum with normality, with its extreme form being clinically expressed as schizophrenia.
SourceAvailable from: Goran OpacicPsihologija 01/2012; 45(2):139-154. DOI:10.2298/PSI1202139V · 0.28 Impact Factor
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ABSTRACT: Sparse evidence of a co-aggregation of the risk of schizophrenia and bipolar disorder provides support for a shared but nonspecific genetic etiology of bipolar disorder and schizophrenia. Temperaments are conceptualized as trait sub-syndromic conditions of major pathologies. This study set out to test the hypothesis of a continuum between schizotypy and affective temperaments versus the alternative hypothesis of their independence based on a cross-sectional, survey design involving 649 (males: 47%) college students. The short 39-item TEMPS-A and the SPQ were used as measures of the affective temperaments and of schizotypy, respectively. Confirmatory factor analyses were applied to a unidimensional model, to a standard correlate traits model, to second-order representations of a common latent structure, and to a bifactor model. Confirmatory bifactor modeling provided evidence against a complete independence of the dimensions subsumed by the affective and the schizotypal traits. The best solution distinguished between two sub-domains grouping positive symptoms and negative symptoms as measured by the SPQ subscales, and a sub-domain related to the affective temperaments as measured by the TEMPS-A. Limitations due to the use of subscales from two different tools should be taken into account.Psychiatry Research 11/2014; DOI:10.1016/j.psychres.2014.10.027 · 2.68 Impact Factor
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ABSTRACT: Objective: We investigated cognitive inhibition in non-clinical individuals with schizotypal traits using event-related potentials. Methods: College students with psy-chometrically defined schizotypal traits (n = 16) and normal controls (n = 15) participated. The computer-ized Stroop task with three types of stimuli, i.e., con-gruent, incongruent, and neutral words, was used to measure cognitive inhibition. Results: The schizotypal-trait group committed significantly more errors in response to incongruent words than did the control group. The control group showed frontal negativity (FN) of significantly greater amplitude in response to incongruent than to congruent and neutral stimuli, whereas the schizotypal-trait group showed no sig-nificant difference in FN amplitude between incon-gruent and congruent/neutral stimuli at 300 -400 ms poststimulus. A source localization analysis conducted in different waveforms for incongruent minus con-gruent conditions at 300 -400 ms poststimulus showed reduced activation in the left cingulate cortex and in the middle/medial prefrontal cortex in the schizo-typal-trait group compared with the control group. The two groups did not differ in the sustained poten-tial amplitudes observed at 550 -650 ms after stimu-lus-onset at parietal sites. Conclusions: These results suggest that individuals with schizotypal traits have difficulties in conflict detection and cognitive inhibi-tion, possibly mediated by the cingulate cortex and prefrontal cortex.