Adaptive and maladaptive features of schizotypy clusters in a community sample

Metacognition as a Transdiagnostic Determinant of Recovery in Schizotypy and Schizophrenia Spectrum Disorders

The term schizotypy refers to the latent personality organization that is thought to underpin the liability to develop schizophrenia and associated disorders. Metacognition, or the ability to understand and form increasingly complex and integrated ideas of oneself, others, and one's community, has been proposed to be an important transdiagnostic construct across schizophrenia spectrum disorders and a range of both clinical and non-clinical manifestations of schizotypy. In this paper, we review evidence that deficits in metacognition are present in individuals with relatively high levels of schizotypy and that these deficits are related to symptomology, function, and quality of life. We address the idea that decrements in metacognition may also contribute to the progression from schizotypy to more severe manifestations, while the amelioration of these deficits may enhance aspects of recovery, including the ability to form an integrated sense of self, others, and the wider world. We also review the following two recovery-oriented psychotherapies that target metacognition to promote recovery in individuals with clinical manifestations of schizotypy: Evolutionary Systems Therapy for Schizotypy (ESTS) and Metacognitive Reflection and Insight Therapy (MERIT).

Can you believe your eyes? Positive schizotypy is associated with increased susceptibility to the Müller-Lyer illusion

BACKGROUND AND HYPOTHESIS

Visual illusions provide a unique opportunity to understand cognitive and perceptual alterations in schizophrenia-spectrum conditions. Schizophrenia patients often exhibit increased susceptibility to the Müller-Lyer illusion. Here, we investigate susceptibility to the Müller-Lyer visual illusion in the general population with different levels of schizotypy.

STUDY DESIGN

We assessed a population-based convenience sample (N = 263) on an online platform. In addition to basic demographics, participants completed the Müller-Lyer illusion, the Cardiff Anomalous Perceptions Scale (CAPS) to measure perceptual anomalies, and the Multidimensional Schizotypy Scale - Brief (MSS-B) for schizotypic traits. To evaluate what predicts susceptibility to the illusion, we fitted a large set of multilevel logistic regression models and performed model averaging over the coefficients.

STUDY RESULTS

We found support for increased illusion susceptibility among individuals with high positive schizotypy. However, we did not find a comparable effect for anomalous perceptions alone, or for negative or disorganized schizotypy.

CONCLUSIONS

The increased Müller-Lyer effect in positive schizotypy might be specific to delusion-like beliefs and magical ideation. Further research is needed to clarify how a hierarchical Bayesian formulation of brain function (e.g. imbalances between bottom-up perceptual processing and substantial reliance on prior expectations) can account for the Müller-Lyer effect in schizophrenia-spectrum conditions.

A comparative study of theory of mind in taxon-like clusters of psychometric schizotypes and individuals at genetic risk for schizophrenia

Introduction: Clinical and family studies suggest that alterations of theory of mind (ToM) represent a marker of genetic liability to schizophrenia. Findings regarding ToM in schizotypy are less consistent. The study aimed to explore whether this might be due to an insufficient account of the heterogeneity of schizotypy in prior research and/or the fact that in psychometric schizotypy ToM alterations could manifest as subtle peculiarities rather than overt errors of mentalising.Methods: Individuals without a family history of psychosis (n = 150) were assigned to low, positive, negative, and high mixed schizotypy classes based on a cluster analysis of 1322 subjects who completed the Schizotypal Personality Questionnaire. The classes were compared on their performance of faux pas tasks with 77 adult first-degree relatives of schizophrenia patients, who represent individuals at genetic risk for schizophrenia. Besides overt errors, subtle alterations in ToM were analysed using expert judgment.Results: The relatives tended to make overt errors and demonstrated specific features of intentional reasoning. None of the schizotypal classes showed similar trends.Conclusions: The results complement the literature on the subjective-objective disjunction in psychometric schizotypes and did not provide evidence that ToM anomalies are a marker of genetic liability to schizophrenia in this cohort.

Ambiguous handedness and visuospatial pseudoneglect in schizotypy in physical and computer-generated virtual environments

Virtual reality (VR) technology has increased clinical attention in the health care of schizophrenia spectrum disorders in both diagnoses of the symptoms and assessment of schizotypal traits. However, the exact nature of VR-induced positive treatment effect in schizotypy is still unknown. In this study, VR technology was used as a non-invasive neurocognitive trigger to test the asymmetric visuospatial representational instability found in individuals with high schizotypy. The study aimed to reveal the brain functional hemispheric laterality in physical and virtual realities in individuals with schizotypal traits. Fifty-one healthy, right-handed participants (24 males and 27 females) were enrolled through public advertisements. Hemispheric functional asymmetry was measured by the Line Bisection Task (LBT). The results revealed that (a) LBT bias in the physical reality showed a handedness-related leftward pseudoneglect, however, similar handedness-related pseudoneglect in VR has not been found. (b) Comparing LBT bias in physically real and VR environments showed rightward drift in VR environments independently to the degree of handedness. (c) The schizotypy has no association with handedness, however, the cognitive schizotypy is related to the LBT bias. Higher cognitive schizotypy in VR associated with left hemispatial pseudoneglect. In conclusion, schizotypy is associated with ambiguous behavioral and cognitive functional laterality. In individuals with high cognitive schizotypy, the VR environment enhanced the representational articulation of the left hemispace. This effect may be originated from the enhancement of the right hemisphere overactivation and is followed by a lower mental control of the overt behavior.

Positive schizotypy is associated with amplified mnemonic discrimination and attenuated generalization

Tendency to experience inaccurate beliefs alongside perceptual anomalies constitutes positive schizotypal traits in the general population and shows continuity with the positive symptoms of schizophrenia. It has been hypothesized that the positive symptomatology of schizophrenia, and by extension, the odd beliefs and unusual perceptual experiences in the general population, are associated with specific alterations in memory functions. An imbalance between memory generalization and episodic memory specificity has been proposed on several counts; however, the direction of the imbalance is currently unclear. Here, we evaluated the association between positive schizotypy, and memory alterations related to hippocampal computations in a general population sample enriched for positive schizotypy. We found that memory generalization is attenuated while memory specificity is elevated in participants with more pronounced positive schizotypal traits. Our findings show that people who are prone to irrational beliefs and unusual experiences also show measurable alterations in memory and likely have difficulty grasping the global picture and rather be overpowered by fragments of information.

Errors of Verbal Episodic Memory in Schizophrenia Patients and in Non-Clinical Group with Different Profiles of Schizotypal Traits

The aim of the study was to provide a fine grain analysis of errors generated on word list learning tasks by schizophrenia patients and healthy controls with different profiles of schizotypal traits, since it can shed light on the cognitive mechanisms of memory impairment in these cohorts. 511 patients (mean age 33.40±11.53 years; 57% women) and 307 healthy controls (mean age 25.20±7.64 years; 73% women) completed the Rey Auditory Verbal Learning Test (A. Rey, 1964). The healthy subjects were assigned to groups with low, high, positive and negative schizotypy based on the Schizotypal Personality Questionnaire adapted by A.G. Efremov and S.N. Enikolopov (2002). In patients, symptomatology was assessed with the Positive and Negative Syndrome Scale adapted by S.N. Mosolov (2001). We analyzed the number of extra-list intrusions, their perseverations, frequency and strength of the associations with stimuli, as well as phonetic intrusions, intrusions from interference trails, and false recognition of semantic and phonetic lures. The results showed that patients are characterized by an increase in the number of extra-list intrusions and their perseverations, proactive interference and recognition of semantic lures; similar trends regarding extra-list intrusions and false recognitions were observed in the high schizotypy group. The data can be interpreted in favor of the idea of impairment of reality monitoring and insufficient encoding of stimulus’s surface features as inherent deficits of information processing in schizophrenia.