Developmental changes in the endorsement of psychotic-like experiences from middle childhood through young adulthood.

BACKGROUND: Children tend to endorse psychotic-like experiences (PLEs) at higher rates than adults, although little is known about how specific symptom endorsement changes across the span of development. Here we take an observational approach to examine trends in PLE endorsement by age in two non-clinical samples: one of school-aged children and another of late adolescents and early adults. METHODS: Prodromal Questionnaire-Brief (child and adult versions) responses were investigated in individuals ages 9-13 (n = 11865) and 16-24 (n = 3209) from the Adolescent Brain and Cognitive Development Study (ABCD) and the Multisite Assessment of Psychosis-risk Study (MAP), respectively. Item-level endorsement and distressing item frequencies were examined by age throughout both cohorts. RESULTS: Unusual perceptual experiences were generally endorsed more heavily in childhood, while other PLEs were endorsed in adolescents and adults up to 4.8 times more frequently than in children. Additionally, certain experiences were endorsed by as many as 73 percent of the older sample. CONCLUSIONS: Considerations for the measurement of PLEs in childhood and adolescence are underscored. Findings from these two samples provide a window into the course of these PLEs and may serve as a scaffold for future research investigating normative versus risk-related experiences during development.

Item-level endorsement on the Prodromal Questionnaire in a large non-clinical sample.

BACKGROUND: Brief questionnaires, such as the Prodromal Questionnaire (PQ) positive scale, have been used to pre-screen individuals who may be at clinical high-risk (CHR) for psychosis. Despite the apparent utility of the PQ, few studies have examined response styles in non-clinical settings, which this study aimed to assess. METHODS: Response frequencies were examined for PQ positive subscale items in 3584 students (ages 18-35) from a nationally representative, semi-public undergraduate institution. Highly endorsed items were evaluated further in conjunction with established cutoffs and associated symptom ratings from the Structured Interview for Psychosis-risk Syndromes (SIPS) in a smaller subset of participants (n = 162). Positive subscale and distressing item responses were also evaluated by gender, race, and ethnicity using measurement invariance analyses and by comparing the relative proportion of individuals above established cutoffs. RESULTS: Fifteen symptoms were endorsed by over 20 % of the sample with as high as 71 % of respondents endorsing them. Responses to 12 of these items were not associated with ratings on the SIPS. The PQ functioned similarly across demographic characteristics with strong evidence found for gender and race invariance across items and strong ethnicity invariance and partial invariance for positive subscale items and distressing items, respectively. CONCLUSIONS: These findings suggest that a commonly used psychosis-risk questionnaire may not be appropriate for non-clinical samples, with the possibility of high false positive rates of those at CHR for psychosis. Future large-scale epidemiological studies should evaluate if psychosis-risk screeners can be improved to identify CHR individuals in community settings.

Testing a Novel Web-Based Neurocognitive Battery in the General Community: Validation and Usability Study.

BACKGROUND: In recent years, there has been increased interest in the development of remote psychological assessments. These platforms increase accessibility and allow clinicians to monitor important health metrics, thereby informing patient-centered treatment. OBJECTIVE: In this study, we report the properties and usability of a new web-based neurocognitive assessment battery and present a normative data set for future use. METHODS: A total of 781 participants completed a portion of 8 tasks that captured performance in auditory processing, visual-spatial working memory, visual-spatial learning, cognitive flexibility, and emotional processing. A subset of individuals (n=195) completed a 5-question survey measuring the acceptability of the tasks. RESULTS: Between 252 and 426 participants completed each task. Younger individuals outperformed their older counterparts in 6 of the 8 tasks. Therefore, central tendency data metrics were presented using 7 different age bins. The broad majority of participants found the tasks interesting and enjoyable and endorsed some interest in playing them at home. Only 1 of 195 individuals endorsed not at all for the statement, "I understood the instructions." Older individuals were less likely to understand the instructions; however, 72% (49/68) of individuals over the age of 60 years still felt that they mostly or very much understood the instructions. CONCLUSIONS: Overall, the tasks were found to be widely acceptable to the participants. The use of web-based neurocognitive tasks such as these may increase the ability to deploy precise data-informed interventions to a wider population.

Neuroimaging Markers of Resiliency in Youth at Clinical High Risk for Psychosis: A Qualitative Review.

Psychotic disorders are highly debilitating and constitute a major public health burden. Identifying markers of psychosis risk and resilience is a necessary step toward understanding etiology and informing prevention and treatment efforts in individuals at clinical high risk (CHR) for psychosis. In this context, it is important to consider that neural risk markers have been particularly useful in identifying mechanistic determinants along with predicting clinical outcomes. Notably, despite a growing body of supportive literature and the promise of recent findings identifying potential neural markers, the current work on CHR resilience markers has received little attention. The present review provides a brief overview of brain-based risk markers with a focus on predicting symptom course. Next, the review turns to protective markers, examining research from nonpsychiatric and schizophrenia fields to build an understanding of framing, priorities, and potential, applying these ideas to contextualizing a small but informative body of resiliency-relevant CHR research. Four domains (neurocognition, emotion regulation, allostatic load, and sensory and sensorimotor function) were identified and are discussed in terms of behavioral and neural markers. Taken together, the literature suggests significant predictive value for brain-based markers for individuals at CHR for psychosis, and the limited but compelling resiliency work highlights the critical importance of expanding this promising area of inquiry.

Transcranial Direct Current Stimulation over the Dorsolateral Prefrontal Cortex in Schizophrenia: A Quantitative Review of Cognitive Outcomes.

Cognitive deficits are a core and disabling feature of psychotic disorders, specifically schizophrenia. Current treatments for impaired cognition in schizophrenia remain insufficient. Recent research suggests transcranial direct current stimulation (tDCS) targeting the dorsolateral prefrontal cortex can potentiate cognitive improvements in healthy individuals and those with psychiatric conditions, such as schizophrenia. However, this burgeoning literature has not been quantitatively evaluated. Through a literature search and quantitative review, we identified 194 papers on tDCS, psychosis, and cognition. Selection criteria included pre/post design and sham control to achieve specific sham-adjusted effect sizes. The 6 retained studies all address schizophrenia populations and include single and repeated stimulation, as well as within and between subject designs. Small positive effects were found for anodal stimulation on behavioral measures of attention and working memory, with tentative findings for cognitive ability and memory. Cathodal stimulation yielded a small positive effect on behaviorally measured cognitive ability. Neurophysiological measures of attention showed a small to medium down-modulation effect for anodal stimulation. Implications of these findings and guidelines for future research are discussed. As revealed by this report, due to the paucity of data available, much remains unknown regarding the clinical efficacy of tDCS in schizophrenia.