Associations between intraindividual reaction time variability and prospective memory performance in patients with schizophrenia and healthy controls.

Introduction: Patients with schizophrenia exhibit prospective memory (PM) impairment. Intraindividual reaction time variability (IIRTV) is an index of attentional control that is required for PM. This study examined the differences in IIRTV between patients with schizophrenia and healthy controls and the relationship between IIRTV and PM performance.Method: Thirty-nine patients with schizophrenia and forty-two healthy controls were recruited to complete a PM task and the Sustained Attention to Response Task. IIRTV was calculated as the coefficient of variation (mean/SD) of reaction time over correctly responded trials in these tasks.Results: Patients with schizophrenia showed lower PM accuracy and increased IIRTV, while the associations between PM accuracy and IIRTV were significant in healthy controls but not in patients with schizophrenia.Conclusion: These findings suggest impaired PM and relationship between PM and attentional control in patients with schizophrenia.

Dissociation of Proactive and Reactive Cognitive Control in Individuals with Schizotypy: An Event-Related Potential Study.

OBJECTIVE: Patients with schizophrenia and individuals with schizotypy, a subclinical group at risk for schizophrenia, have been found to have impairments in cognitive control. The Dual Mechanisms of Cognitive Control (DMC) framework hypothesises that cognitive control can be divided into proactive and reactive control. However, it is unclear whether individuals with schizotypy have differential behavioural impairments and neural correlates underlying these two types of cognitive control. METHOD: Twenty-five individuals with schizotypy and 26 matched healthy controls (HCs) completed both reactive and proactive control tasks with electroencephalographic data recorded. The proportion of congruent and incongruent trials was manipulated in a classic colour-word Stroop task to induce proactive or reactive control. Proactive control was induced in a context with mostly incongruent (MI) trials and reactive control in a context with mostly congruent (MC) trials. Two event-related potential (ERP) components, medial frontal negativity (MFN, associated with conflict detection) and conflict sustained potential (conflict SP, associated with conflict resolution) were examined. RESULTS: There was no significant difference between the two groups in terms of behavioural results. In terms of ERP results, in the MC context, HC exhibited significantly larger MFN (360-530 ms) and conflict SP (600-1000 ms) amplitudes than individuals with schizotypy. The two groups did not show any significant difference in MFN or conflict SP in the MI context. CONCLUSIONS: The present findings provide initial evidence for dissociation of neural activation between proactive and reactive cognitive control in individuals with schizotypy. These findings help us understand cognitive control deficits in the schizophrenia spectrum.

Exploring the links between alexithymia, empathy and schizotypy in college students using network analysis.

Introduction: Impaired empathy is one of the major dysfunctions commonly found in patients with schizophrenia, with alexithymia being one possible underlying factor. Schizotypy represents a set of psychotic-like manifestations, investigation of which may contribute to our understanding of psychosis while minimising the confounding effects of illness chronicity and medication exposure. Few studies have specifically examined the associations among alexithymia, empathy and schizotypy. Methods: We investigated the relationships among alexithymia, empathy and schizotypy in college students using network analysis. The Interpersonal Reactivity Index (IRI), Toronto Alexithymia Scale (TAS), and Chapman Psychosis-Proneness scales were captured, and network based on the subscales were estimated in 552 participants. Strength, closeness and betweenness of nodes were calculated to measure the centrality. Results: Network analyses revealed a pattern connecting alexithymia with empathy and schizotypy. Negative connections between empathy and physical/social anhedonia and positive edges linking alexithymia with empathy and social anhedonia were observed. Conclusions: Network constructed in the study demonstrated alexithymia's role in empathic deficits. Our findings highlighted the connections between components of empathy, alexithymia and schizotypy.

The effect and mechanisms of implementation intentions on prospective memory in individuals with and without schizotypal personality features.

Prospective memory (PM) refers to remembering to do something at a future time. Studies have shown that implementation intention can improve PM performance. The present study aimed to examine the effect and mechanism of implementation intention on PM in individuals prone for schizotypal personality disorder (SPD proneness) in a laboratory condition. A total of 51 participants with SPD proneness and 51 controls were administered a PM task. They were further randomly assigned to an implementation intention condition and a typical instruction condition. All participants completed the PM task with low and high cognitive load conditions. The results showed that implementation intention improved PM performances in both SPD prone and control groups, indicating that implementation intention was an effective strategy for improving PM performance. However, the mechanisms were different for the two groups. For controls, implementation intention did not affect their cognitive resources allocation strategy. Participants with SPD proneness allocated significantly more cognitive resources to the PM task in the implementation intention condition.

Relationship between theta/beta ratio and mind wandering in schizotypy.

Negative association was found between the frontal theta/beta ratio and mind wandering in participants with high schizotypal traits, while no such association was found in participants with low schizotypal traits. These findings provide insights into the neural mechanism of mind wandering in individuals with high schizotypal traits.

Developmental trajectories of schizotypal personality disorder-like behavioural manifestations: a two-year longitudinal prospective study of college students.

BACKGROUND: Previous evidence has shown that schizotypal personality disorder (SPD) is part of the schizophrenia spectrum. Few studies have examined latent classes in the developmental trajectories of SPD features over time in individuals with SPD features. METHODS: We adopted a longitudinal prospective study design to follow up a cohort of 660 college students during a two-year period. Participants' SPD-like symptoms and psychosocial function were measured by a comprehensive set of questionnaires that covered SPD features and cognitive, emotional, and psychosocial functions. Latent class growth analysis was used to examine the trajectory classes. RESULTS: Three trajectory classes were identified: a low, a medium, and a high SPD features group. Participants in the low group reported few SPD features and their symptoms declined over time. The medium group students had more SPD features than the low group and these symptoms stabilized during the follow up period. Participants in the high group reported the most SPD features and their symptoms increased over time. The three groups differed in paranoid thoughts, psychological distress, neurocognition function, and emotional expression over time. Results of multivariate regression analysis suggested that paranoid thoughts, emotional experience and prospective memory were predictors of social functioning in the high SPD feature group. CONCLUSIONS: Our findings suggest that individuals with SPD features may be delineated into different developmental subgroups and these subgroups differ significantly in psychosocial function. Delusions, emotion, and prospective memory may be important features to consider in early diagnosis and interventions for individuals predisposed to SPD and schizophrenia.

Proactive and reactive response inhibition of individuals with high schizotypy viewing different facial expressions: An ERP study using an emotional stop-signal task.

The present study aimed to examine whether impairments in reactive (outright stopping) and proactive (preparation for stopping) response inhibition are affected by negative emotions in individuals with high schizotypy, a subclinical group at risk for schizophrenia, as well as the neural mechanisms underlying these processes. Twenty-seven participants with high schizotypy and 28 matched low-schizotypy individuals completed an emotional stop-signal task in which they responded to facial emotions (neutral or angry) or inhibited their responses (when the frame of the picture turned red). Electroencephalogram (EEG) data were also recorded during the task. At the neural level, analysis of go trials revealed that viewing angry faces impaired proactive inhibition. In addition, the high-schizotypy group exhibited a greater P3 amplitude in go trials in the neutral condition than the low-schizotypy group; however, no group difference was found in the angry condition. For stop trials (reactive inhibition), a smaller P3 amplitude was found in the angry condition than in the neutral condition. Moreover, high-schizotypy individuals showed smaller P3 amplitudes than low-schizotypy individuals. The current findings suggest that, at the neural level, viewing negative emotions impaired both proactive and reactive response inhibition. Individuals with high schizotypy exhibited impairments in proactive response inhibition in the neutral condition but not in the angry condition; they exhibited impaired reactive response inhibition in both emotion conditions. The present findings deepen our understanding of emotional response inhibition in individuals on the schizophrenia spectrum.

Proactive and reactive cognitive control for emotional conflict in individuals with high schizotypy: An ERP study.

OBJECTIVE: The present study aimed to examine how individuals with high schizotypy, a high risk group of schizophrenia patients, resolve emotional conflict in proactive and reactive control and the underlying neural mechanisms. METHODS: Thirty-two individuals with high schizotypy and 30 matched individuals with low schizotypy completed an emotional face-word Stroop task with electroencephalographic data recorded. The proportion of incongruent trials was manipulated in the task to induce proactive control (mostly incongruent trials context, MI context) or reactive control (mostly congruent trials context, MC context). Two event-related potential (ERP) components (N170 and N2) were examined, which represent face processing and cognitive control processes, respectively. RESULTS: In the MC context, significantly decreased N2 and N170 amplitudes were found in high schizotypy individuals compared with low schizotypy individuals, suggesting abnormal neural activity of reactive control in high schizotypy individuals. No significant differences were found between the two groups in the MI context. CONCLUSIONS: These results provide initial evidence for dissociation of neural activity of proactive and reactive control on emotional conflict in individuals with high schizotypy. SIGNIFICANCE: The current findings provide important insight into the emotional conflict resolution in the schizophrenia spectrum.

Neural correlates of mental time travel in individuals with high level of schizotypy.

BACKGROUND: Mental time travel (MTT) is the ability to re-experience past events (autobiographic memory, AM) and pre-experience possible future events (episodic future thinking, EFT) through mental simulation. Empirical findings suggest that individuals with high level of schizotypy exhibit MTT impairment. However, the neural correlates of this impairment remain unclear. METHOD: Thirty-eight individuals with high level of schizotypy and 35 low level of schizotypy were recruited to complete an MTT imaging paradigm. Participants were required to recall past events (AM condition), imagine possible future events (EFT condition) related to cue words, or generate exemplars related to category words (control condition) while undergoing functional Magnetic Resonance Imaging (fMRI). RESULTS: AM showed greater activation in precuneus, bilateral posterior cingulate cortex, thalamus, and middle frontal gyrus than EFT. Individuals with high level of schizotypy exhibited reduced activation in the left anterior cingulate cortex during AM (vs. Control) and in the medial frontal gyrus during EFT (vs. Control) compared to individuals with low level of schizotypy. Although psychophysiological interaction analyses did not show any significant group difference, individuals with high level of schizotypy exhibited functional connectivity between left anterior cingulate cortex (seed) and right thalamus, between medial frontal gyrus (seed) and left cerebellum during MTT, whereas individuals with low level of schizotypy did not exhibit these functional connectivities. CONCLUSION: These findings suggest that decreased brain activations may underlie MTT deficits in individuals with high level of schizotypy.

Mental time travel for self and others in individuals with a high level of schizotypy.

Mental time travel (MTT) is the ability to project oneself to the past or future through mental simulation. Moreover, MTT can involve self-related or other-related information. This study aimed to compare MTT in individuals with high levels of schizotypy and that in their counterparts with low levels of schizotypy. Participants with high (n = 37) and low (n = 37) levels of schizotypy completed an MTT task with four conditions [2 (Condition: self vs. other) × 2 (Time orientation: past vs. future)]. They were required to recall past events that had happened to themselves or to a non-intimate person, and to imagine possible future events that might happen to themselves or to a non-intimate person, related to cue words. Outcome measures included specificity, vividness, sense of experience, emotional valence, emotional intensity, proportion of first-person visual perspective in events, and difficulty in event generation. A 2 (Group: high vs. low levels of schizotypy) × 2 (Condition) × 2 (Time orientation) mixed analysis of variance was conducted on each index. Results showed that self-related MTT was more specific than other-related MTT in low levels of schizotypy participants but not in high levels of schizotypy participants. Participants with a high level of schizotypy reported fewer specific events, and reported events with lower vividness and positive emotion than did those with a low level of schizotypy. Self-related MTT showed higher levels of phenomenological characteristics than did other-related MTT. In conclusion, individuals with a high level of schizotypy have altered MTT, and cannot benefit from the self-advantage effect on the specificity of MTT.

The relationship between schizotypal traits and satisfaction with life among Chinese young adults: The mediating effect of trait anxiety and mind wandering.

Schizotypal traits have been found to be negatively associated with satisfaction with life but the underlying mechanisms are not well understood. This study investigated the association between schizotypal traits and satisfaction with life and explored the mediating role of trait anxiety and mind wandering in the relationship between those two variables in a sample of Chinese young adults. One hundred and two individuals with high schizotypal traits and 104 individuals with low schizotypal traits were screened using the Schizotypal Personality Questionnaire. They completed a series of questionnaires including the Satisfaction with Life Scale, Trait Anxiety Inventory, and Mind Wandering Questionnaire. Results showed that: First, the high schizotypal trait group showed lower satisfaction with life, and higher trait anxiety and mind wandering frequency than the low schizotypal trait group. Second, the high schizotypal trait group, trait anxiety, and mind wandering negatively predicted satisfaction with life. Third, mediation analyses showed that all indirect effect paths in the mediation model were significant, that is, trait anxiety and mind wandering alone and together mediated the relationship between schizotypal trait group and satisfaction with life. In conclusion, high schizotypal trait is a risk factor for low satisfaction with life. The association between schizotypal traits and satisfaction with life was mediated by the combination of trait anxiety and mind wandering. This study has implications for improving life satisfaction in individuals with high schizotypal traits.

Prospective memory performance and its improvement in individuals with high schizotypal traits: Evidence from eye-tracking studies.

OBJECTIVE: This study aimed to examine prospective memory (PM) performance and the potential effect of implementation intention on PM performance and the underlying mechanisms in individuals with high schizotypyal traits (HSTs) using eye-tracking paradigms. METHODS: In Experiment 1, 30 individuals with HSTs and 30 individuals with low schizotypal traits (LSTs) underwent a visual search task that involved PM cues, and participants' eye movements were recorded. In Experiment 2, 50 individuals with HSTs were randomly assigned to the implementation intention group and typical instruction group. RESULTS: In Experiment 1, individuals with HSTs had a lower PM accuracy and performed less PM cue monitoring (indicated by fewer total fixation counts on distractor words) than individuals with LSTs. In Experiment 2, implementation intention significantly improved PM accuracy and increased total fixation counts on distractor words in individuals with HSTs compared to the HST group with typical instruction. CONCLUSIONS: Individuals with HSTs were impaired in PM and showed reduced cue monitoring compared to individuals with LSTs. Implementation intention improved PM performance and facilitated cue monitoring in individuals with HSTs. SIGNIFICANCE: Our findings indicate that cue monitoring may be an important process of intervention target for PM for individuals in the schizophrenia spectrum.

Involuntary mental time travel in individuals with schizotypal personality features.

Involuntary mental time travel (MTT) refers to the phenomenon of mentally reliving past experiences or pre-living possible future events in an involuntary form. Few studies have explored involuntary MTT in individuals with schizotypal personality features. The present study aimed to first explore the psychometric properties of the Involuntary Autobiographic Memory Inventory (IAMI) in a Chinese sample (Study 1), and then to explore whether individuals with schizotypal personality features experience involuntary MTT more frequently than individuals without schizotypal features. Moreover, the study explored whether the aberrant frequency of involuntary MTT is correlated with positive schizotypal features (Study 2). The results showed that the IAMI had good structural validity and reliability in a Chinese sample. Individuals with schizotypal traits reported a significantly higher frequency, less positive emotion, and stronger emotional intensity for both involuntary memories and future thoughts compared with individuals without schizotypal features. Further analyses in individuals with schizotypal personality features showed that the frequencies of both involuntary memories and future thoughts were significantly correlated with positive schizotypal traits. These results have potential theoretical and clinical implications for a comprehensive understanding of involuntary MTT among individuals with schizotypal personality features.

Applying network analysis to investigate the links between dimensional schizotypy and cognitive and affective empathy.

BACKGROUND: Although impairment in empathy has been reported in schizophrenia spectrum disorders, little is known about the relationship between empathy and schizotypal traits. This study examines this relationship by applying network analysis to a large sample collected at 18-months follow-up in a longitudinal dataset. METHODS: One thousand four hundred and eighty-six college students were recruited and completed a set of self-reported questionnaires on empathy, schizotypy, depression, anxiety and stress. Networks were constructed by taking the subscale scores of these measures as nodes and partial correlations between each pair of nodes as edges. Network Comparison Tests were performed to investigate the differences between individuals with high and low schizotypy. RESULTS: Cognitive and affective empathy were strongly connected with negative schizotypy in the network. Physical and social anhedonia showed high centrality measured by strength, closeness and betweenness while anxiety and stress showed high expected influence. Predictability ranged from 22.4% (personal distress) to 79.9% (anxiety) with an average of 54.4%. Compared with the low schizotypy group, the high schizotypy group showed higher global strength (S = 0.813, p < 0.05) and significant differences in network structure (M = 0.531, p < 0.001) and strength of edges connecting empathy with schizotypy (adjusted ps < 0.05). LIMITATIONS: Only self-rating scales were used, and disorganized schizotypy was not included. CONCLUSIONS: Our findings suggest that the cognitive and affective components of empathy and dimensions of schizotypy are closely related in the general population and their network interactions may play an important role in individuals with high schizotypy.

The structural invariance of the Temporal Experience of Pleasure Scale across time and culture.

The Temporal Experience of Pleasure Scale (TEPS) is a self-report instrument that assesses pleasure experience. Initial scale development and validation in the United States yielded a two-factor solution comprising anticipatory and consummatory pleasure. However, a four-factor model that further parsed anticipatory and consummatory pleasure experience into abstract and contextual components was a better model fit in China. In this study, we tested both models using confirmatory factor analysis in an American and a Chinese sample and examined the configural measurement invariance of both models across culture. We also examined the temporal stability of the four-factor model in the Chinese sample. The results indicated that the four-factor model of the TEPS was a better fit than the two-factor model in the Chinese sample. In contrast, both models fit the American sample, which also included many Asian American participants. The four-factor model fit both the Asian American and Chinese samples equally well. Finally, the four-factor model demonstrated good measurement and structural invariance across culture and time, suggesting that this model may be applicable in both cross-cultural and longitudinal studies.

Prospection deficits in schizophrenia: Evidence from clinical and subclinical samples.

Previous research has revealed anticipatory pleasure deficits in people with schizophrenia and people with social anhedonia but who do not have schizophrenia. Prospection is an important component of anticipatory pleasure, but little is known about the role of prospection in social anhedonia. In 2 studies, we investigated prospection and anticipatory pleasure in people with schizophrenia and people with social anhedonia using an affective prospection task and a self-report measure, the Temporal Experience of Pleasure Scale (TEPS). In Study 1, we found that people with schizophrenia (n = 31) reported less TEPS anticipatory pleasure, generated less rich and vivid prospections, and reported less preexperiencing of future events than people without schizophrenia (n = 29). In Study 2, we found that people with social anhedonia (n = 34) reported less TEPS anticipatory pleasure, generated less rich prospections, and reported less pleasure and preexperiencing for future events than people without social anhedonia (n = 33). Taken together, prospection impairments and decreased anticipatory pleasure were observed in schizophrenia and social anhedonia. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

An attempt at revisiting the factor structure of the Dysexecutive Questionnaire in the Chinese setting.

This study examined the factor structure of the Chinese version of the Dysexecutive Questionnaire (DEX) in a large nonclinical sample of college students (n = 1,586). All participants completed the self-report version of the DEX. An exploratory factor analysis was first performed on a sub-sample (randomly split, n = 766) and produced a four-factor model (Volition, Intentionality, Inhibition, and Abstract Problem-Solving), which was similar to previous models reported in Western samples. In addition, a series of confirmatory factor analyses was conducted on the remaining sample (n = 820). The findings suggested that a four-factor solution of the self-report DEX might better explain the latent structure in the present healthy Chinese sample.

Cross Cultural Validation and Extension of the Clinical Assessment Interview for Negative Symptoms (CAINS) in the Chinese Context: Evidence from a Spectrum Perspective.

The Clinical Assessment Interview for Negative Symptoms (CAINS) was designed in accordance with the recent theory and research in social affective neuroscience and to address the psychometric and conceptual limitations of other instruments assessing negative symptoms. The present study aimed to provide a large-scale validation of the CAINS in China and examine its applicability and validity evidence across the schizophrenia spectrum. Using confirmatory factor analysis, our results replicated the original findings in the US development samples that the CAINS possesses a stable 2-factor structure, namely "motivation/pleasure" and "expression". We also found significant correlations between the CAINS and other negative symptom measures. The CAINS demonstrated good discriminant validity in differentiating negative symptoms in people with schizophrenia, nonpsychotic first-degree relatives and people with social anhedonia. People with schizophrenia exhibited significantly higher CAINS subscale scores than first-degree relatives and healthy controls. In addition, first-degree relatives had higher "motivation/pleasure" scores than healthy controls. The "motivation/pleasure" subscale scores of individuals with social anhedonia were also significantly higher than healthy controls.

Low-pleasure beliefs in patients with schizophrenia and individuals with social anhedonia.

Anhedonia in schizophrenia has been suggested to comprise a set of low-pleasure beliefs, defined as beliefs that certain things/activities were not pleasurable or that one does not feel pleasant generally. However, no instrument has been intentionally developed to specifically measure low-pleasure beliefs, and there is a paucity of empirical evidence for low-pleasure beliefs and their relationship with anhedonia in both patients with schizophrenia and individuals with high social anhedonia. We developed and validated the Beliefs About Pleasure Scale (BAPS) using non-clinical (Studies 1, 2 & 3), chronic schizophrenia (Study 2), and first episode schizophrenia (Study 3) samples. Across these studies, we examined psychometric properties of the BAPS, including temporal stability, internal consistency, factor structure, and convergent validity. The 22 BAPS items loaded onto 4 factors, namely the "Devaluation of Pleasure", the "Pleasurable Activity Expectancies", the "Negative Outcomes Expectancies", and the "Attention to Pleasure". The measure demonstrated good internal consistency and convergent validity in each sample. Moreover, both individual with schizophrenia and non-clinical participants with high social anhedonia scored higher on the BAPS than controls (Study 3), supporting construct validity. These findings provide preliminary evidence for the presence of low-pleasure beliefs in both clinical and subclinical groups and suggest that the BAPS has promising initial psychometric properties. The BAPS will be useful for exploring the cognitive component of anhedonia and provides a novel assessment for mechanism of change in psychosocial treatment studies.

Trajectories of schizotypy and their emotional and social functioning: An 18-month follow-up study.

Schizotypy is a set of personality traits that convey liability to develop schizophrenia. Studying schizotypy in healthy individuals may facilitate the understanding of the psychopathological processes underlying schizophrenia. The present study aimed to examine the developmental trajectories of schizotypy over time using a longitudinal study design. The Chapman Scales for Psychosis Proneness were administered to 1541 college students at baseline, and subsequently at six-monthly intervals up to 18months. Latent class growth analysis was conducted to track the different trajectories. In addition, self-reported scales were used to measure idea of reference, emotional experiences and expression, stress and coping, as well as social functioning. We identified four latent classes with distinct trajectories: "nonschizotypy" group (LC1), "stable high schizotypy" group (LC3), "high reactive schizotypy" group (LC2) and "low reactive schizotypy" group (LC4). These findings suggest that there may be distinct developmental trajectories for schizotypy. Two groups may be of particular interest: the "stable high schizotypy" group that displayed the worst clinical and functioning outcomes on almost all measures and the "high reactive schizotypy" group characterized by a relatively rapid decline in functioning.