Theory of mind and schizotypy: A meta-analysis

Neuropsychology and Neurobiology of Negative Schizotypy: A Selective Review

Schizotypy refers to a latent personality organization that reflects liability to schizophrenia. Because schizotypy is a multidimensional construct, people with schizotypy vary in behavioral and neurobiological features. In this article, we selectively review the neuropsychological and neurobiological profiles of people with schizotypy, with a focus on negative schizotypy. Empirical evidence is presented for alterations of neuropsychological performance in negative schizotypy. We also cover the Research Domain Criteria domains of positive valence, social process, and sensorimotor systems. Moreover, we systematically summarize the neurobiological correlates of negative schizotypy at the structural, resting-state, and task-based neural levels, as well as the neurochemical level. The convergence and inconsistency of the evidence are critically reviewed. Regarding theoretical and clinical implications, we argue that negative schizotypy represents a useful organizational framework for studying neuropsychology and neurobiology across different psychiatric disorders.

Towards a scalable approach to assess speech organization across the psychosis-spectrum -online assessment in conjunction with automated transcription and extraction of speech measures

Automatically extracted measures of speech constitute a promising marker of psychosis as disorganized speech is associated with psychotic symptoms and predictive of psychosis-onset. The potential of speech markers is, however, hampered by (i) lengthy assessments in laboratory settings and (ii) manual transcriptions. We investigated whether a short, scalable data collection (online) and processing (automated transcription) procedure would provide data of sufficient quality to extract previously validated speech measures. To evaluate the fit of our approach for purpose, we assessed speech in relation to psychotic-like experiences in the general population. Participants completed an 8-minute-long speech task online. Sample 1 included measures of psychometric schizotypy and delusional ideation (N = 446). Sample 2 included a low and high psychometric schizotypy group (N = 144). Recordings were transcribed both automatically and manually, and connectivity, semantic, and syntactic speech measures were extracted for both types of transcripts. 73%/86% participants in sample 1/2 completed the experiment. Nineteen out of 25 speech measures were strongly (r > 0.7) and significantly correlated between automated and manual transcripts in both samples. Amongst the 14 connectivity measures, 11 showed a significant relationship with delusional ideation. For the semantic and syntactic measures, On Topic score and the Frequency of personal pronouns were negatively correlated with both schizotypy and delusional ideation. Combined with demographic information, the speech markers could explain 11-14% of the variation of delusional ideation and schizotypy in Sample 1 and could discriminate between high-low schizotypy with high accuracy (0.72-0.70, AUC = 0.78-0.79) in Sample 2. The moderate to high retention rate, strong correlation of speech measures across manual and automated transcripts and sensitivity to psychotic-like experiences provides initial evidence that online collected speech in combination with automatic transcription is a feasible approach to increase accessibility and scalability of speech-based assessment of psychosis.

Schizotypy Moderates the Relationship Between Sleep Quality and Social Cognition

ABSTRACT

Poor sleep quality has been tied to worse social cognition. Social cognitive deficits have been noted in those with high schizotypy. Yet, no study has assessed whether schizotypy moderates the relationship between sleep quality and social cognition, which may be vital to our understanding of contributors to social functioning. We conducted a cross-sectional analysis of associations of sleep quality and social cognition, with potential moderation by schizotypy. Participants ( n = 906) completed self-report measures of schizotypy, sleep quality, and social cognition. Levels of schizotypy significantly moderated some of the relationships between sleep and social cognition. For participants low in total or interpersonal schizotypy, worse sleep quality was associated with worse theory of mind scores. For participants low in total, disorganized, or cognitive perceptual schizotypy, worse sleep quality was associated with worse self-reported cognitive empathy. For those high in these facets of schizotypy, worse sleep quality was associated with better self-reported cognitive empathy. These results suggest that the individual facets of schizotypy provide additional information and, therefore, are important to assess when examining social cognition and sleep.

Cold executive function processes and their hot analogs in schizotypy

OBJECTIVE

To examine cold (based on logical reasoning) versus hot (having emotional components) executive function processes in groups with high individual schizotypal traits.

METHOD

Two-hundred and forty-seven participants were administered the Schizotypal Personality Questionnaire and were allocated into schizotypal (cognitive-perceptual, paranoid, negative, disorganized) or control groups according to pre-specified criteria. Participants were also administered a battery of tasks examining working memory, complex selective attention, response inhibition, decision-making and fluid intelligence and their affective counterparts. The outcome measures of each task were reduced to one composite variable thus formulating five cold and five hot cognitive domains. Between-group differences in the cognitive domains were examined with repeated measures analyses of covariance.

RESULTS

For working memory, the control and the cognitive-perceptual groups outperformed negative schizotypes, while for affective working memory controls outperformed the disorganized group. Controls also scored higher compared with the disorganized group in complex selective attention, while both the control and the cognitive-perceptual groups outperformed negative schizotypes in complex affective selective attention. Negative schizotypes also had striking difficulties in response inhibition, as they scored lower compared with all other groups. Despite the lack of differences in fluid intelligence, controls scored higher compared with all schizotypal groups (except from cognitive-perceptual schizotypes) in emotional intelligence; the latter group reported higher emotional intelligence compared with negative schizotypes.

CONCLUSION

Results indicate that there is no categorical association between the different schizotypal dimensions with solely cold or hot executive function processes and support impoverished emotional intelligence as a core feature of schizotypy.

Pathways from childhood trauma to aberrant salience: A structural equation approach to mentalization model

OBJECTIVE

The aim of this study was to explore the relationship between affective disturbances and aberrant salience in the context of childhood trauma, attachment, and mentalization in an analogue study.

METHODS

Using a cross-sectional design, an online community sample completed self-report measures of key variables. Structural equation modelling was used to test childhood trauma's influence on aberrant salience via a set of intermediate risk factors (depression, negative schizotypy, and insecure attachment). These intermediate risk factors were assumed to lead to the proximal risk factors of aberrant salience (i.e., disorganized schizotypy and disorganized attachment) depending on the vulnerability of mentalizing capacity to elevated stress.

RESULTS

The sample (N = 1263) was 78% female and aged between 18 and 35 years. The tested models closely fitted the observed data, revealing significant pathways from childhood trauma to aberrant salience via the hypothesized pathways. The direct effect of childhood trauma on aberrant salience was significant.

CONCLUSION

Findings suggest that the pathway to aberrant salience may be characterized by disorganization of self-state and intersubjectivity as a function of diminishment in mentalizing ability. This may relate to changes in attachment organization and socio-cognitive capacity, which could constitute possible risk factors signalling development of aberrant salience.

The Effects of Cannabidiol and δ-9-Tetrahydrocannabinol in Social Cognition: A Naturalistic Controlled Study

Background: Social cognition abilities such as empathy and the Theory of Mind (ToM) have been shown to be impaired in neuropsychiatric conditions such as psychotic, autistic, and bipolar disorders. The endocannabinoid system (ECS) seems to play a role in social behavior and emotional processing while it also seems to play a role in those neuropsychiatric conditions showing social cognition impairments. Main plant cannabinoids delta-9-tetrahydrocannabinol (THC) and cannabidiol (CBD) modulate the ECS and, due to their opposite effects, have been proposed as both cause and treatment for neuropsychiatric-related disorders such as schizophrenia, anxiety, or post-traumatic stress disorder (PTSD). The aim of this study was to test the effects of THC and CBD on social cognition abilities in chronic cannabis users. Method: Eighteen members from a cannabis social club were tested for social cognition effects under the effects of different full spectrum cannabis extracts containing either THC, CBD, THC+CBD, or placebo in a naturalistic randomized double-blind crossover placebo-controlled study. Results: Results showed that participants under the effects of THC showed lower cognitive empathy when compared with the effects of CBD but not when those were compared with THC+CBD or placebo. Also, participants showed higher cognitive ToM under the effects of CBD when compared with the effects of placebo, but not when those were compared with THC or THC+CBD. However, we did not find differences on the emotional scales for empathy or ToM. Conclusions: This study provides evidence for the interaction between the effects of THC and CBD and social cognition abilities in a naturalistic environment, which can be of special interest for the clinical practice of medical cannabis on neuropsychiatric disorders. We show for the first time that CBD can improve ToM abilities in chronic cannabis users. Our results might help to understand the role of the ECS in social cognition, and their association with psychiatric and neurodevelopmental disorders such as schizophrenia or autism. Finally, we demonstrate how reliable methodologies can be implemented in naturalistic environments to collect valid ecological evidence outside classic laboratory settings.

Online speech assessment of the psychotic spectrum: Exploring the relationship between overlapping acoustic markers of schizotypy, depression and anxiety

BACKGROUND

Remote assessment of acoustic alterations in speech holds promise to increase scalability and validity in research across the psychosis spectrum. A feasible first step in establishing a procedure for online assessments is to assess acoustic alterations in psychometric schizotypy. However, to date, the complex relationship between alterations in speech related to schizotypy and those related to comorbid conditions such as symptoms of depression and anxiety has not been investigated. This study tested whether (1) depression, generalized anxiety and high psychometric schizotypy have similar voice characteristics, (2) which acoustic markers of online collected speech are the strongest predictors of psychometric schizotypy, (3) whether including generalized anxiety and depression symptoms in the model can improve the prediction of schizotypy.

METHODS

We collected cross-sectional, online-recorded speech data from 441 participants, assessing demographics, symptoms of depression, generalized anxiety and psychometric schizotypy.

RESULTS

Speech samples collected online could predict psychometric schizotypy, depression, and anxiety symptoms with weak to moderate predictive power, and with moderate and good predictive power when basic demographic variables were added to the models. Most influential features of these models largely overlapped. The predictive power of speech marker-based models of schizotypy significantly improved after including symptom scores of depression and generalized anxiety in the models (from R2 = 0.296 to R2 = 0. 436).

CONCLUSIONS

Acoustic features of online collected speech are predictive of psychometric schizotypy as well as generalized anxiety and depression symptoms. The acoustic characteristics of schizotypy, depression and anxiety symptoms significantly overlap. Speech models that are designed to predict schizotypy or symptoms of the schizophrenia spectrum might therefore benefit from controlling for symptoms of depression and anxiety.

Contrasting social knowledge and theory of mind patterns in adults with personality disorders, schizophrenia spectrum disorders, and healthy controls

INTRODUCTION

Personality disorders (PD) and schizophrenia spectrum disorders (SSD) are distinct conditions displaying common symptoms, like impairments in social cognition, that make them hard to distinguish, especially in severe cases. To date, few studies have compared theory of mind skills in these two disorders, and none have compared social knowledge skills. This study aims to compare the social cognitive abilities of patients with these conditions.

METHOD

Non-parametric analyses of covariance were used to compare severe PD patients (n = 37), SSD patients (n = 44), and healthy controls (HC; n = 49) on the Social Knowledge Test and two measures of theory of mind: the Reading the Mind in the Eyes Test and the Combined Stories Test, which incorporates items from various widely used tests.

RESULTS

While no significant group differences were found on the Social Knowledge Test, SSD patients performed lower than the HC group on both theory of mind tests. PD patients only had lower performance than the HC group on specific items from the Combined Stories Test.

CONCLUSIONS

PD and SSD patients demonstrated distinctive patterns of social cognitive impairments, with items of greater complexity or with an affective orientation being the most discriminant for PD.

Auditory P300 in individuals with high schizotypy: associations of schizotypal traits with amplitude and latency under different oddball conditions

Background

The aim of this study was to compare the characteristics of auditory P300 between non-clinical individuals with high and low schizotypal traits, and investigate the relationship between schizotypy and P300 under various oddball conditions.

Methods

An extreme-group design was adopted. After screening 1,519 young adults using the Schizotypal Personality Questionnaire (SPQ), sixty-three participants were chosen and divided into two groups (schizotypy group: 31 participants; control group: 32 participants). Basic demographic information was assessed and matched between groups. Depression and anxiety indexes were evaluated and controlled. The P300 component was evoked by an auditory oddball paradigm with different frequencies and durations.

Results

(1) The duration P300 amplitude at PZ site was significantly weaker in the schizotypy group than in the control group [F(1,54) = 7.455, p = 0.009, η_p² = 0.121]. (2) In the schizotypy group, the latency of frequency P300 at PZ site under large-variant oddball condition was significantly correlated with total SPQ scores (r_p = 0.451, p = 0.018) and disorganized dimension scores (r_p = 0.381, p = 0.050). (3) In the control group, significantly negative correlations was found between the negative dimension score of SPQ and the frequency P300 amplitudes under small variant condition (PZ: r_p = -0.393, p = 0.043; CPZ: r_p = -0.406, p = 0.035). In addition, a significant negative relationship was found between disorganized dimension scores and the duration P300 latency at CPZ site under large-variant oddball condition (r_p = -0.518, p = 0.006). Moreover, a significant negative association was found between the duration P300 amplitude at CPZ site under small-variant oddball condition and negative factor scores (r_p = -0.410, p = 0.034).

Conclusion

Individuals with high schizotypal traits were likely to have deficient attention and hypoactive working memory for processing auditory information, especially the duration of sounds. P300 effects were correlated with negative and disorganized schizotypy, rather than positive schizotypy. There were diverse patterns of relationship between schizotypal traits and P300 under different oddball conditions, suggesting that characteristics and parameters of target stimuli should be considered cautiously when implementing an auditory oddball paradigm for individuals with schizophrenia spectrum.

Activation of the left medial temporal gyrus and adjacent brain areas during affective theory of mind processing correlates with trait schizotypy in a nonclinical population

Schizophrenia, a severe psychiatric disorder, is associated with abnormal brain activation during theory of mind (ToM) processing. Researchers recently suggested that there is a continuum running from subclinical schizotypal personality traits to fully expressed schizophrenia symptoms. Nevertheless, it remains unclear whether schizotypal personality traits in a nonclinical population are associated with atypical brain activation during ToM tasks. Our aim was to investigate correlations between fMRI brain activation during affective ToM (ToMA) and cognitive ToM (ToMC) tasks and scores on the Schizotypal Personality Questionnaire (SPQ) and the Basic Empathy Scale in 39 healthy individuals. The total SPQ score positively correlated with brain activation during ToMA processing in clusters extending from the left medial temporal gyrus (MTG), lingual gyrus and fusiform gyrus to the parahippocampal gyrus (Brodmann area: 19). During ToMA processing, the right inferior occipital gyrus, right MTG, precuneus and posterior cingulate cortex negatively correlated with the emotional disconnection subscore and the total score of self-reported empathy. These posterior brain regions are known to be involved in memory and language, as well as in creative reasoning, in nonclinical individuals. Our findings highlight changes in brain processing associated with trait schizotypy in nonclinical individuals during ToMA but not ToMC processing.

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.

Negative Schizotypy Mediates the Relationship Between Metacognition and Social Functioning in a Nonclinical Sample

ABSTRACT

Reduced metacognitive abilities-difficulty making sense of and understanding oneself and others-have been found to be key predictors of social functioning across a range of clinical and nonclinical groups. However, the exact processes through which metacognition impacts social functioning are unclear. This study examined whether subclinical negative symptoms mediated the relationship between metacognition and social functioning in a nonclinical sample of young adults (n = 98). Results demonstrated that lower metacognitive mastery was found to be uniquely associated with greater subclinical negative symptoms, whereas higher subclinical negative symptoms were associated with reduced social functioning. Further, the effects of lower metacognition on reduced social function were mediated by subclinical negative symptoms and not positive or disorganized subclinical symptoms. Results suggest that subclinical negative symptoms may link reductions in metacognition with social functioning in nonclinical samples. Training aimed at enhancing metacognition may support normative social functioning in the general population.

Activation of the default network during a theory of mind task predicts individual differences in agreeableness and social cognitive ability

Social cognitive processes, such as emotion perception and empathy, allow humans to navigate complex social landscapes and are associated with specific neural systems. In particular, theory of mind (ToM), which refers to our ability to decipher the mental states of others, is related to the dorsal medial prefrontal cortex and temporoparietal junction, which include portions of the default network. Both social cognition and the default network have been linked to the personality trait Agreeableness. We hypothesized that default network activity during a ToM task would positively predict social cognitive abilities and Agreeableness. In a 3T fMRI scanner, participants (N = 1050) completed a ToM task in which they observed triangles displaying random or social (i.e., human-like) movement. Participants also completed self-report measures of Agreeableness and tests of intelligence and social cognitive ability. In each participant, average blood oxygen level dependent responses were calculated for default network regions associated with social cognition, and structural equation modeling was used to test associations of personality and task performance with activation in those brain regions. Default network activation in the dorsal medial subsystem was greater for social versus random animations. Default network activation in response to social animations predicted better performance on social cognition tasks and, to a lesser degree, higher Agreeableness. Neural response to social stimuli in the default network may be associated with effective social processing and could have downstream effects on social interactions. We discuss theoretical and methodological implications of this work for social and personality neuroscience.

Classification of Low and High Schizotypy Levels via Evaluation of Brain Connectivity

Schizotypy is a latent cluster of personality traits that denote a vulnerability for schizophrenia or a type of spectrum disorder. The aim of the study is to investigate parametric effective brain connectivity features for classifying high versus low schizotypy (LS) status. Electroencephalography (EEG) signals are recorded from 13 high schizotypy (HS) and 11 LS participants during an emotional auditory odd-ball task. The brain connectivity signals for machine learning are taken after the settlement of event-related potentials. A multivariate autoregressive (MVAR)-based connectivity measure is estimated from the EEG signals using the directed transfer functions (DTFs) method. The values of DTF power in five standard frequency bands are used as features. The support vector machines (SVMs) revealed significant differences between HS and LS. The accuracy, specificity, and sensitivity of the results using SVM are as high as 89.21%, 90.3%, and 88.2%, respectively. Our results demonstrate that the effective brain connectivity in prefrontal/parietal and prefrontal/frontal brain regions considerably changes according to schizotypal status. These findings prove that the brain connectivity indices offer valuable biomarkers for detecting schizotypal personality. Further monitoring of the changes in DTF following the diagnosis of schizotypy may lead to the early identification of schizophrenia and other spectrum disorders.

N400 Peculiarities During Intentional Inferences Production in Subjects With Schizotypal Traits

Abstract. A deficit in context processing may underlie theory of mind (ToM) difficulties in schizophrenia, although few studies to date have explored the impact of contextual processing on ToM performances within the same task. We used electroencephalography to investigate the production of intentional inferences from highly versus weakly structured sentences in healthy participants with schizotypal traits. Thirty-four participants were divided into two groups according to their scores on the Schizotypal Personality Questionnaire (SPQ). The participants listened to stories that required a degree of understanding in order to produce an inference about the main character’s intention. Each story was followed by a target word that could either be highly predictable (HP), weakly predictable (WP), or incompatible with the context. The results indicate that the N400 component for WP targets was stronger in the high-SPQ group. This increase correlated with the negative dimension of schizotypy. This may reflect difficulties with generating intentional inferences when the context is insufficiently structured for high schizotypy participants.

Auditory acuity and musical ability in young adults with high schizotypal traits

BACKGROUND

Despite auditory cognition dysfunction being consistently found in people with schizophrenia, the evidence from non-clinical individuals with schizotypy is rare and inconsistent. No studies thus far have comprehensively assessed the association among auditory perception, musical cognition, and schizotypy in non-clinical samples.

AIM

We aimed to explore abnormalities in auditory skills, from basic perception to musical ability, among individuals with schizotypal traits.

METHOD

An extreme-group design was adopted. Sixty-six participants from the schizotypy and control groups were screened from 1093 young adults using the Schizotypal Personality Questionnaire (SPQ). Auditory acuity was assessed using four auditory discrimination threshold tests, and musical ability was evaluated through the Montreal Battery of Evaluation of Amusia (MBEA). Basic demographic information and musical backgrounds were assessed and matched, and depression, anxiety, and digit-span index were evaluated and controlled.

RESULTS

Elevated sensitivity in auditory perception and improved musical talent were found in young adults with high schizotypal traits. Auditory acuity and musical ability were positively correlated with schizotypy and its factors among participants across groups. A regression analysis in the control group showed that cognitive perceptual scores of SPQ positively predicted auditory temporal sensitivity. The mediation analysis revealed an indirect effect of pure tone duration discrimination between musical rhythmic ability and positive factor of schizotypy.

DISCUSSION

Elevated sensitivity in auditory temporal perception and improved musical talent in young adults with high schizotypy may contribute to explaining the variation of auditory process in the development of schizophrenia-spectrum disorders. It can also help elucidate the association between psychopathology and creativity in auditory modality.

Empathy and Theory of Mind in Ultra-High Risk for Psychosis: Relations With Schizotypy and Executive Function

OBJECTIVE

While recent studies have found deficits in theory of mind (ToM) skills in individuals at ultra-high risk (UHR) for psychosis, empathic tendencies in these subjects remain unclear. The presence of high schizotypy and compromised executive functions, which are found in UHR individuals, would affect ToM skills and empathic tendencies. We investigated the ToM skills and empathic tendencies of UHR individuals and examined their relationship with schizotypy and executive function.

METHODS

This study included 28 UHR individuals and 28 age- and sex-matched healthy controls. All participants completed a self-reported empathic scale (Interpersonal Reactivity Index) and the Wisconsin Schizotypy Scales. Additionally, the ToM Picture Stories Task and Wisconsin Card Sorting Test were conducted.

RESULTS

UHR individuals showed a trend toward lower self-reported empathic tendencies; however, there were no differences in ToM skills between the two groups. Of the four subscales of the IRI, only empathic concern showed a significant difference between the two groups. Empathic concern was inversely associated with negative schizotypy.

CONCLUSION

Our findings suggest that UHR individuals show relatively preserved cognitive empathy but compromised emotional empathy. Furthermore, in UHR individuals, the empathic concern subscale of the IRI was associated with negative schizotypy, while ToM skills were related to positive schizotypy and executive function.

Social Cognition and Friendships in Adolescents With Autistic-Like Experiences and Psychotic-Like Experiences

Autism spectrum conditions (ASC) and schizophrenia spectrum conditions (SSC) are both characterized by changes in social-cognitive functioning. Less is known about the overlap and the differences in social-cognitive functioning when comparing individuals with subclinical levels of ASC and SSC, while studies in non-clinical samples have the benefit of avoiding confounds that are present in clinical groups. Therefore, we first examined how autistic-like experiences, positive psychotic-like experiences and the co-occurrence of both correlated with the performance on an extensive battery of social cognition tasks in young adolescents. Second, we examined the effect of autistic-like experiences, psychotic-like experiences and their co-occurrence on friendships in daily life. A total of 305 adolescents (Mage = 12.6, sd = 0.4, 147 boys) participated in the current study. A battery of social cognition tasks, comprising the Reading the Mind in the Eyes task, Dot perspective task and trust game were individually administered in a classroom setting, along with a friendship peer nomination questionnaire. Results indicated no evidence for a relationship between the performance on the social cognition battery and subclinical experiences of autism and/or psychosis. However, results did show that the amount of autistic-like experiences of adolescents were associated with being less often selected as a friend by their peers. By contrast, no relationship between self-reported friendships and autistic-like experiences was found. Neither a relationship between friendships and psychotic-like experiences was reported. This study provides initial evidence that information provided by peers may shed light on (altered) social behavior associated with autistic-like experiences that is not apparent on performance measures, as well as elucidate possible differences between autistic- and psychotic-like experiences.