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Research on individuals at clinical high risk for psychological and physical disorders has grown exponentially in recent years, with a variety of new screening tools and early intervention techniques being implemented. One recent example is Attenuated Psychosis Syndrome, a diagnosis for individuals who are at clinical high risk for psychosis, which was recently included in Section III of theDiagnostic and Statistical Manual of Mental Disorders(5th ed.). Given the focus on prevention at early stages, at-risk individuals will continue to be a topic of significance not only in psychosis research but also in other illnesses. This document provides a comprehensive summary of the ethical dilemmas that clinicians or researchers may encounter in this domain, and possible actions consistent with the currentCanadian Code of Ethics for Psychologists. We use clinical high risk for psychosis and theCanadian Code of Ethics for Psychologistsas a way to illuminate these ethical issues; however, application to other jurisdictions and disciplines, as well as other high-risk populations, is also of relevance. [ABSTRACT FROM AUTHOR]

Cognitive deficits are consistently demonstrated in individuals with schizophrenia. Cognitive training involves structured exercises prescribed and undertaken with the intention of enhancing cognitive abilities such as attention, memory, and problem solving. Thus, cognitive training represents a potentially promising intervention for enhancing cognitive abilities in schizophrenia. However, cognitive training programs are numerous and heterogeneous, hence, the generalizability of training related outcomes can be challenging to assess. This article will provide a brief overview of current literature on cognitive training and explore how knowledge of working memory training in healthy populations can potentially be applied to enhance cognitive functioning of individuals with schizophrenia. [ABSTRACT FROM AUTHOR]

Dear Editor, The biological mechanisms underlying the efficacy of lithium therapy remain largely unknown. Here, we report a replication of our previous results - higher neurite density within the left frontal cortex - in patients under lithium therapy compared with patients without lithium therapy, in a completely independent sample. [Extracted from the article]

Stress has a detrimental impact on memory, the hippocampus, and psychological health. Psychopathology research on stress has centered mainly on psychiatric diagnoses rather than symptom dimensions, and less attention has been given to the neurobiological factors through which stress might be translated into psychopathology. The present work investigates the transdiagnostic relationship of cumulative stress with episodic memory and the hippocampus (both structure and function) and explores the extent to which stress mediates the relationship between personality psychopathology and hippocampal size and activation. Cumulative lifetime stress was assessed in a sample of females recruited to vary in stress exposure and severity of personality psychopathology. Fifty-six participants completed subjective and objective tests of episodic memory, a T2-weighted high-resolution magnetic resonance imaging (MRI) scan of the medial-temporal lobe, and functional MRI (fMRI) scanning during a learning and recognition memory task. Higher cumulative stress was significantly related to memory complaints (but not episodic memory performance), lower bilateral hippocampal volume, and greater encoding-related hippocampal activation during the presentation of novel stimuli. Furthermore, cumulative stress significantly mediated the relationship between personality psychopathology and both hippocampal volume and activation, whereas alternative mediation models were not supported. The findings suggest that structural and functional activation differences in the hippocampus observed in case-control studies of psychiatric diagnoses may share cumulative stress as a common factor, which may mediate broadly reported relationships between psychopathology and hippocampal structure and function. [ABSTRACT FROM AUTHOR]

The organization of the Hierarchical Taxonomy of Psychopathology (HiTOP) model provides unique opportunities to evaluate whether neural risk measures operate as indicators of broader latent liabilities (e.g., externalizing proneness) or narrower expressions (e.g., antisociality and alcohol abuse). Following this approach, the current study recruited a sample of 182 participants (54% female) who completed measures of externalizing psychopathology (also internalizing) and associated traits. Participants also completed three tasks (Flanker-No Threat, Flanker-Threat, and Go/No-Go tasks) with event-related potential (ERP) measurement. Three variants of two research domain criteria (RDoC)-based neurophysiological indicators—P3 and error-related negativity (ERN)—were extracted from these tasks and used to model two latent ERP factors. Scores on these two ERP factors independently predicted externalizing factor scores when accounting for their covariance with sex—suggesting distinct neural processes contributing to the broad externalizing factor. No predictive relation with the broad internalizing factor was found for either ERP factor. Analyses at the finer-grained level revealed no unique predictive relations of either ERP factor with any specific externalizing symptom variable when accounting for the broad externalizing factor, indicating that ERN and P3 index general liability for problems in this spectrum. Overall, this study provides new insights about neural processes in externalizing psychopathology at broader and narrower levels of the HiTOP hierarchy. General Scientific Summary: The Hierarchical Taxonomy Model of Psychopathology argues that some etiological factors might operate at broader levels of the psychopathological spectrum, conferring general risk for clinical problems. Our results show that error-related negativity (ERN) and P3 responses are indicators of distinct neural processes and that both account for externalizing proneness. [ABSTRACT FROM AUTHOR]

Theory of mind (ToM) refers to the ability to make inferences about mental states. Thus far, little research has examined ToM development in middle childhood. Importantly, recent studies have distinguished between making inferences about beliefs (cognitive ToM) and emotions (affective ToM). ToM has also been associated with executive functioning, though research on the differential relations between cognitive ToM and affective ToM and specific components of executive functioning is scarce. The current study examined advanced cognitive and affective ToM in 8-to 11-year-olds (N = 168). Working memory, inhibition, and set-shifting abilities were also assessed. Results showed that, in this age group, cognitive ToM increased significantly with age, and combined cognitive and affective ToM trendwise increased with age. All three domains of executive functioning (EF) showed age-related improvement. Inhibitory control and verbal IQ significantly predicted cognitive ToM, whereas verbal IQ predicted affective ToM. These results suggest that cognitive and affective components of ToM are distinguishable and may be differentially related to EF. [ABSTRACT FROM AUTHOR]

Commercial computerized cognitive training (CCT) programs have grown rapidly in popularity over the past several years. However, the effectiveness of commercial CCT at improving cognition is highly contested, and the degree to which expectations of CCT outcomes affect self-reported gains remains unclear. Here, we examined the malleability of CCT expectations by testing if a brief positive or negative message about CCT would influence attitudes regarding its effectiveness in 565 participants from Amazon's Mechanical Turk. We also assessed if personality, need for cognition (NFC), and fixed versus incremental theories of intelligence (TOI) moderate these effects. As predicted, individuals in the positive condition had more positive CCT expectations relative to those in the negative condition. Individuals with incremental TOI had more positive expectations than fixed TOI individuals, regardless of message condition. Higher NFC and open-mindedness were associated with more positive expectations in the positive condition and more negative expectations in the negative condition. Agreeableness was associated with more positive expectations in the positive condition. These results indicate that CCT expectations are malleable to persuasive messages, and this effect is influenced by NFC, TOI, open-mindedness, and agreeableness. The results support the need for future research to investigate expectancy effects on CCT outcomes. • Persuasive messages about cognitive training influenced training expectations. • Individuals with higher need for cognition were more influenced by the messages. • Incremental theory of intelligence was associated with more optimistic expectations. • Agreeableness and openness were associated with being influenced by the messages. [ABSTRACT FROM AUTHOR]

A dimensionality reduction method was used to determine the task-timing-related functional brain networks underlying the Raven's Standard Progressive Matrices (RSPM), a non-verbal estimate of fluid intelligence (Gf). We identified five macro-scale task-based blood‑oxygen-level-dependent (BOLD)-signal brain networks and interpreted their network-level task-induced BOLD changes to provide functional interpretations separately for each network. This led to new observations about the brain networks underlying the RSPM: (1) the multiple demand network (MDN) for solution searching peaked early in the trial (∼9 s peak), followed by response (RESP) for response selection (∼12 s), and re-evaluation (RE-EV) for solution checking (∼18 s peak), (2) high activity in the MDN was correlated with high activity in the later-peaking RE-EV network, proposed to underpin cooperative solution searching (MDN) and checking (RE-EV) processes, and (3) high activity in the MDN in all conditions was associated with low accuracy in the hard RSPM condition, suggesting that those with lower performance on hard problems allocate more resources into solution-searching across all conditions. These findings corroborate the MDN's significance in Gf solution searching, and add the RE-EV network as playing an important checking role, providing overlap with the proposed abstraction/elaboration and hypothesis testing phases of the Parieto-Frontal Integration Theory (P-FIT). Therefore, this set of results not only supports past theoretical work on the brain networks underlying Gf and the RSPM task, but extends it by providing more complete anatomical, temporal, and functional information based on a set of brain task-based networks which replicate over many tasks. • Retrieved 5 fMRI brain networks elicited during RSPM: anatomical and temporal data. • The MDN had searching-style role; worked with RE-EV to check solutions. • Lower performance in hard RSPM problems linked to more activation in the MDN. • Anatomical description and temporal stages of P-FIT are supported and expanded. [ABSTRACT FROM AUTHOR]

Schizophrenia is characterized by the misattribution of emotional significance to neutral faces, accompanied by overactivations of the limbic system. To understand the disorder's genetic and environmental contributors, investigating healthy first-degree relatives is crucial. However, inconsistent findings exist regarding their ability to recognize neutral faces, with limited research exploring the cerebral correlates of neutral face processing in this population. Thus, we here investigated brain responses to neutral face processing in healthy first-degree relatives through an image-based meta-analysis of functional magnetic resonance imaging studies. We included unthresholded group-level T-maps from 5 studies comprising a total of 120 first-degree relatives and 150 healthy controls. In sensitivity analyses, we ran a combined image- and coordinate-based meta-analysis including 7 studies (157 first-degree relatives, 207 healthy controls) aiming at testing the robustness of the results in a larger sample of studies. Our findings revealed a pattern of decreased brain responses to neutral faces in relatives compared with healthy controls, particularly in limbic areas such as the bilateral amygdala, hippocampus, and insula. The same pattern was observed in sensitivity analyses. These results contrast with the overactivations observed in patients, potentially suggesting that this trait could serve as a protective factor in healthy relatives. However, further research is necessary to test this hypothesis., (© 2024. The Author(s).)

First-degree relatives of patients diagnosed with schizophrenia (SZ-FDRs) show similar patterns of brain abnormalities and cognitive alterations to patients, albeit with smaller effect sizes. First-degree relatives of patients diagnosed with bipolar disorder (BD-FDRs) show divergent patterns; on average, intracranial volume is larger compared to controls, and findings on cognitive alterations in BD-FDRs are inconsistent. Here, we performed a meta-analysis of global and regional brain measures (cortical and subcortical), current IQ, and educational attainment in 5,795 individuals (1,103 SZ-FDRs, 867 BD-FDRs, 2,190 controls, 942 schizophrenia patients, 693 bipolar patients) from 36 schizophrenia and/or bipolar disorder family cohorts, with standardized methods. Compared to controls, SZ-FDRs showed a pattern of widespread thinner cortex, while BD-FDRs had widespread larger cortical surface area. IQ was lower in SZ-FDRs (d = -0.42, p = 3 × 10 -5 ), with weak evidence of IQ reductions among BD-FDRs (d = -0.23, p = .045). Both relative groups had similar educational attainment compared to controls. When adjusting for IQ or educational attainment, the group-effects on brain measures changed, albeit modestly. Changes were in the expected direction, with less pronounced brain abnormalities in SZ-FDRs and more pronounced effects in BD-FDRs. To conclude, SZ-FDRs and BD-FDRs show a differential pattern of structural brain abnormalities. In contrast, both had lower IQ scores and similar school achievements compared to controls. Given that brain differences between SZ-FDRs and BD-FDRs remain after adjusting for IQ or educational attainment, we suggest that differential brain developmental processes underlying predisposition for schizophrenia or bipolar disorder are likely independent of general cognitive impairment., (© 2020 The Authors. Human Brain Mapping published by Wiley Periodicals LLC.)

White matter pathology likely contributes to the pathogenesis of bipolar disorder (BD). Most studies of white matter in BD have used diffusion tensor imaging (DTI), but the advent of more advanced multi-shell diffusion MRI imaging offers the possibility to investigate other aspects of white matter microstructure. Diffusion kurtosis imaging (DKI) extends the DTI model and provides additional measures related to diffusion restriction. Here, we investigated white matter in BD by applying whole-brain voxel-based analysis (VBA) and a network-based connectivity approach using constrained spherical deconvolution tractography to assess differences in DKI and DTI metrics between BD (n = 25) and controls (n = 24). The VBA showed lower mean kurtosis in the corona radiata and posterior association fibers in BD. Regional differences in connectivity were indicated by lower mean kurtosis and kurtosis anisotropy in streamlines traversing the temporal and occipital lobes, and lower mean axial kurtosis in the right cerebellar, thalamo-subcortical pathways in BD. Significant differences were not seen in DTI metrics following FDR-correction. The DKI findings indicate altered connectivity across cortical, subcortical and cerebellar areas in BD. DKI is sensitive to different microstructural properties and is a useful complementary technique to DTI to more fully investigate white matter in BD., (Copyright © 2021 Elsevier B.V. All rights reserved.)

The Hierarchical Taxonomy of Psychopathology (HiTOP) is an empirical structural model of psychological symptoms formulated to improve the reliability and validity of clinical assessment. Neurobiology can inform assessments of early risk and intervention strategies, and the HiTOP model has greater potential to interface with neurobiological measures than traditional categorical diagnoses given its enhanced reliability. However, one complication is that observed biological correlates of clinical symptoms can reflect various factors, ranging from dispositional risk to consequences of psychopathology. In this paper, we argue that the HiTOP model provides an optimized framework for conducting research on the biological correlates of psychopathology from an ontogenetic perspective that distinguishes among indicators of liability, current symptoms, and consequences of illness. Through this approach, neurobiological research can contribute more effectively to identifying individuals at high dispositional risk, indexing treatment-related gains, and monitoring the consequences of mental illness, consistent with the aims of the HiTOP framework.
., (© 2019, AICHServier GroupCopyright © 2019 AICH Servier Group. All rights reserved.)

Background: Schizophrenia and bipolar disorder share genetic liability, and some structural brain abnormalities are common to both conditions. First-degree relatives of patients with schizophrenia (FDRs-SZ) show similar brain abnormalities to patients, albeit with smaller effect sizes. Imaging findings in first-degree relatives of patients with bipolar disorder (FDRs-BD) have been inconsistent in the past, but recent studies report regionally greater volumes compared with control subjects., Methods: We performed a meta-analysis of global and subcortical brain measures of 6008 individuals (1228 FDRs-SZ, 852 FDRs-BD, 2246 control subjects, 1016 patients with schizophrenia, 666 patients with bipolar disorder) from 34 schizophrenia and/or bipolar disorder family cohorts with standardized methods. Analyses were repeated with a correction for intracranial volume (ICV) and for the presence of any psychopathology in the relatives and control subjects., Results: FDRs-BD had significantly larger ICV (d = +0.16, q < .05 corrected), whereas FDRs-SZ showed smaller thalamic volumes than control subjects (d = -0.12, q < .05 corrected). ICV explained the enlargements in the brain measures in FDRs-BD. In FDRs-SZ, after correction for ICV, total brain, cortical gray matter, cerebral white matter, cerebellar gray and white matter, and thalamus volumes were significantly smaller; the cortex was thinner (d < -0.09, q < .05 corrected); and third ventricle was larger (d = +0.15, q < .05 corrected). The findings were not explained by psychopathology in the relatives or control subjects., Conclusions: Despite shared genetic liability, FDRs-SZ and FDRs-BD show a differential pattern of structural brain abnormalities, specifically a divergent effect in ICV. This may imply that the neurodevelopmental trajectories leading to brain anomalies in schizophrenia or bipolar disorder are distinct., (Copyright © 2019 Society of Biological Psychiatry. Published by Elsevier Inc. All rights reserved.)