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BACKGROUND: The Collaborative Outcome study on Health and Functioning during Infection Times (COH-FIT; www.coh-fit.com) is an anonymous and global online survey measuring health and functioning during the COVID-19 pandemic. The aim of this study was to test concurrently the validity of COH-FIT items and the internal validity of the co-primary outcome, a composite psychopathology "P-score". METHODS: The COH-FIT survey has been translated into 30 languages (two blind forward-translations, consensus, one independent English back-translation, final harmonization). To measure mental health, 1-4 items ("COH-FIT items") were extracted from validated questionnaires (e.g. Patient Health Questionnaire 9). COH-FIT items measured anxiety, depressive, post-traumatic, obsessive-compulsive, bipolar and psychotic symptoms, as well as stress, sleep and concentration. COH-FIT Items which correlated r ≥ 0.5 with validated companion questionnaires, were initially retained. A P-score factor structure was then identified from these items using exploratory factor analysis (EFA) and confirmatory factor analyses (CFA) on data split into training and validation sets. Consistency of results across languages, gender and age was assessed. RESULTS: From >150,000 adult responses by May 6th, 2022, a subset of 22,456 completed both COH-FIT items and validated questionnaires. Concurrent validity was consistently demonstrated across different languages for COH-FIT items. CFA confirmed EFA results of five first-order factors (anxiety, depression, post-traumatic, psychotic, psychophysiologic symptoms) and revealed a single second-order factor P-score, with high internal reliability (ω = 0.95). Factor structure was consistent across age and sex. CONCLUSIONS: COH-FIT is a valid instrument to globally measure mental health during infection times. The P-score is a valid measure of multidimensional mental health. ispartof: JOURNAL OF AFFECTIVE DISORDERS vol:326 pages:249-261 ispartof: location:Netherlands status: published

Psychosis presentation can be affected by genetic and environmental factors. Differentiating between affective and non-affective psychosis (A-FEP and NA-FEP, respectively) may influence treatment decisions and clinical outcomes. The objective of this paper is to examine differences between patients with A-FEP or NA-FEP in a Latin American sample.Patients from two cohorts of patients with a FEP recruited from Brazil and Chile. Subjects included were aged between 15 and 30 years, with an A-FEP or NA-FEP (schizophrenia-spectrum disorders) according to DSM-IV-TR. Sociodemographic data, duration of untreated psychosis and psychotic/mood symptoms were assessed. Generalized estimating equation models were used to assess clinical changes between baseline-follow-up according to diagnosis status.A total of 265 subjects were included. Most of the subjects were male (70.9 %), mean age was 21.36 years. A-FEP and NA-FEP groups were similar in almost all sociodemographic variables, but A-FEP patients had a higher probability of being female. At baseline, the A-FEP group had more manic symptoms and a steeper reduction in manic symptoms scores during the follow- up. The NA-FEP group had more negative symptoms at baseline and a higher improvement during follow-up. All domains of The Positive and Negative Syndrome Scale improved for both groups. No difference for DUP and depression z-scores at baseline and follow-up.The sample was recruited at tertiary hospitals, which may bias the sample towards more severe cases.This is the largest cohort comparing A-FEP and NA-FEP in Latin America. We found that features in FEP patients could be used to improve diagnosis and support treatment decisions.

Background Psychosis is related to neurochemical changes in deep-brain nuclei, particularly suggesting dopamine dysfunctions. We used an magnetic resonance imaging-based technique called quantitative susceptibility mapping (QSM) to study these regions in psychosis. QSM quantifies magnetic susceptibility in the brain, which is associated with iron concentrations. Since iron is a cofactor in dopamine pathways and co-localizes with inhibitory neurons, differences in QSM could reflect changes in these processes. Methods We scanned 83 patients with first-episode psychosis and 64 healthy subjects. We reassessed 22 patients and 21 control subjects after 3 months. Mean susceptibility was measured in 6 deep-brain nuclei. Using linear mixed models, we analyzed the effect of case-control differences, region, age, gender, volume, framewise displacement (FD), treatment duration, dose, laterality, session, and psychotic symptoms on QSM. Results Patients showed a significant susceptibility reduction in the putamen and globus pallidus externa (GPe). Patients also showed a significant R2* reduction in GPe. Age, gender, FD, session, group, and region are significant predictor variables for QSM. Dose, treatment duration, and volume were not predictor variables of QSM. Conclusions Reduction in QSM and R2* suggests a decreased iron concentration in the GPe of patients. Susceptibility reduction in putamen cannot be associated with iron changes. Since changes observed in putamen and GPe were not associated with symptoms, dose, and treatment duration, we hypothesize that susceptibility may be a trait marker rather than a state marker, but this must be verified with long-term studies.

Patients with Schizophrenia may show different clinical presentations, not only regarding inter-individual comparisons but also in one specific subject over time. In fMRI studies, functional connectomes have been shown to carry valuable individual level information, which can be associated with cognitive and behavioral variables. Moreover, functional connectomes have been used to identify subjects within a group, as if they were fingerprints. For the particular case of Schizophrenia, it has been shown that there is reduced connectome stability as well as higher inter-individual variability. Here, we studied inter and intra-individual heterogeneity by exploring functional connectomes’ variability and related it with clinical variables (PANSS Total scores and antipsychotic’s doses). Our sample consisted of 30 patients with First Episode of Psychosis and 32 Healthy Controls, with a test–retest approach of two resting-state fMRI scanning sessions. In our patients’ group, we found increased deviation from healthy functional connectomes and increased intragroup inter-subject variability, which was positively correlated to symptoms’ levels in six subnetworks (visual, somatomotor, dorsal attention, ventral attention, frontoparietal and DMN). Moreover, changes in symptom severity were positively related to changes in deviation from healthy functional connectomes. Regarding intra-subject variability, we were unable to replicate previous findings of reduced connectome stability (i.e., increased intra-subject variability), but we found a trend suggesting that result. Our findings highlight the relevance of variability characterization in Schizophrenia, and they can be related to evidence of Schizophrenia patients having a noisy functional connectome.

ObjectiveSchizophrenia is associated with widespread brain-morphological alterations, believed to be shaped by the underlying connectome architecture. This study tests whether large-scale structural reorganization in schizophrenia relates to normative network architecture, in particular regional centrality/hubness and connectivity patterns. We examine network effects in schizophrenia across different disease stages, and transdiagnostically explore consistency of such relationships in patients with bipolar and major depressive disorder.MethodsWe studied anatomical MRI scans from 2,439 adults with schizophrenia and 2,867 healthy controls from 26 ENIGMA sites. Case-control patterns of structural alterations were evaluated against two network susceptibility models: 1) hub vulnerability, which examines associations between regional network centrality and magnitude of disease-related alterations; 2) epicenter models, which identify regions whose typical connectivity profile most closely resembles the disease-related morphological alteration patterns. Both susceptibility models were tested across schizophrenia disease stages and compared to meta-analytic bipolar and major depressive disorder case-control maps.ResultsIn schizophrenia, regional gray matter reductions co-localized with interconnected hubs, in both the functional (r=0.58, pspinspin=0.01). Epicenters were identified in temporo-paralimbic regions, extending to frontal areas. We found unique epicenters for first-episode and early stages, and a shift from occipital to temporal-frontal epicenters in chronic stages. Transdiagnostic comparisons revealed shared epicenters in schizophrenia and bipolar, but not major depressive disorders.ConclusionsCortical reorganization over the course of schizophrenia closely reflects brain network architecture, emphasizing marked hub susceptibility and temporo-frontal epicenters. The observed overlapping epicenters for schizophrenia and bipolar disorder furthermore suggest shared pathophysiological processes within the schizophrenia-bipolar-spectrum.

The 22q11 deletion syndrome is a genetic disorder associated with a high risk of developing psychosis, and is therefore considered a neurodevelopmental model for studying the pathogenesis of schizophrenia. Studies have shown that localized abnormal functional brain connectivity is present in 22q11 deletion syndrome like in schizophrenia. However, it is less clear whether these abnormal cortical interactions lead to global or regional network disorganization as seen in schizophrenia. We analyzed from a graph-theory perspective fMRI data from 40 22q11 deletion syndrome patients and 67 healthy controls, and reconstructed functional networks from 105 brain regions. Between-group differences were examined by evaluating edge-wise strength and graph theoretical metrics of local (weighted degree, nodal efficiency, nodal local efficiency) and global topological properties (modularity, local and global efficiency). Connectivity strength was globally reduced in patients, driven by a large network comprising 147 reduced connections. The 22q11 deletion syndrome network presented with abnormal local topological properties, with decreased local efficiency and reductions in weighted degree particularly in hub nodes. We found evidence for abnormal integration but intact segregation of the 22q11 deletion syndrome network. Results suggest that 22q11 deletion syndrome patients present with similar aberrant local network organization as seen in schizophrenia, and this network configuration might represent a vulnerability factor to psychosis.

22q11.2 deletion syndrome (22q11.2DS) is a genetic neurodevelopmental disorder that represents one of the greatest known risk factors for psychosis. Previous studies in psychotic subjects without the deletion have identified a dopaminergic dysfunction in striatal regions, and dysconnectivity of striatocortical systems, as an important mechanism in the emergence of psychosis. Here, we used resting-state functional MRI to examine striatocortical functional connectivity in 22q11.2DS patients. We used a 2 × 2 factorial design including 125 subjects (55 healthy controls, 28 22q11.2DS patients without a history of psychosis, 10 22q11.2DS patients with a history of psychosis, and 32 subjects with a history of psychosis without the deletion), allowing us to identify network effects related to the deletion and to the presence of psychosis. In line with previous results from psychotic patients without 22q11.2DS, we found that there was a dorsal to ventral gradient of hypo- to hyperstriatocortical connectivity related to psychosis across both patient groups. The 22q11.2DS was additionally associated with abnormal functional connectivity in ventral striatocortical networks, with no significant differences identified in the dorsal system. Abnormalities in the ventral striatocortical system observed in these individuals with high genetic risk to psychosis may thus reflect a marker of illness risk.

Preclinical models propose that increased hippocampal activity drives subcortical dopaminergic dysfunction and leads to psychosis-like symptoms and behaviors. Here, we used multimodal neuroimaging to examine the relationship between hippocampal regional cerebral blood flow (rCBF) and striatal dopamine synthesis capacity in people at clinical high risk (CHR) for psychosis and investigated its association with subsequent clinical and functional outcomes. Ninety-five participants (67 CHR and 28 healthy controls) underwent arterial spin labeling MRI and 18F-DOPA PET imaging at baseline. CHR participants were followed up for a median of 15 months to determine functional outcomes with the global assessment of function (GAF) scale and clinical outcomes using the comprehensive assessment of at-risk mental states (CAARMS). CHR participants with poor functional outcomes (follow-up GAF n = 25) showed higher rCBF in the right hippocampus compared to CHRs with good functional outcomes (GAF ≥ 65, n = 25) (pfwe = 0.026). The relationship between rCBF in this right hippocampal region and striatal dopamine synthesis capacity was also significantly different between groups (pfwe = 0.035); the association was negative in CHR with poor outcomes (pfwe = 0.012), but non-significant in CHR with good outcomes. Furthermore, the correlation between right hippocampal rCBF and striatal dopamine function predicted a longitudinal increase in the severity of positive psychotic symptoms within the total CHR group (p = 0.041). There were no differences in rCBF, dopamine, or their associations in the total CHR group relative to controls. These findings indicate that altered interactions between the hippocampus and the subcortical dopamine system are implicated in the pathophysiology of adverse outcomes in the CHR state.

Over the past few decades, neuroimaging has become a ubiquitous tool in basic research and clinical studies of the human brain. However, no reference standards currently exist to quantify individual differences in neuroimaging metrics over time, in contrast to growth charts for anthropometric traits such as height and weight1. Here we assemble an interactive open resource to benchmark brain morphology derived from any current or future sample of MRI data ( http://www.brainchart.io/ ). With the goal of basing these reference charts on the largest and most inclusive dataset available, acknowledging limitations due to known biases of MRI studies relative to the diversity of the global population, we aggregated 123,984 MRI scans, across more than 100 primary studies, from 101,457 human participants between 115 days post-conception to 100 years of age. MRI metrics were quantified by centile scores, relative to non-linear trajectories2 of brain structural changes, and rates of change, over the lifespan. Brain charts identified previously unreported neurodevelopmental milestones3, showed high stability of individuals across longitudinal assessments, and demonstrated robustness to technical and methodological differences between primary studies. Centile scores showed increased heritability compared with non-centiled MRI phenotypes, and provided a standardized measure of atypical brain structure that revealed patterns of neuroanatomical variation across neurological and psychiatric disorders. In summary, brain charts are an essential step towards robust quantification of individual variation benchmarked to normative trajectories in multiple, commonly used neuroimaging phenotypes., R.A.I.B. was supported by a British Academy Postdoctoral fellowship and by the Autism Research Trust. J. Seidlitz was supported by NIMH T32MH019112-29 and K08MH120564. S.R.W. was funded by UKRI Medical Research Council MC_UU_00002/2 and was supported by the NIHR Cambridge Biomedical Research Centre (BRC-1215-20014). E.T.B. was supported by an NIHR Senior Investigator award and the Wellcome Trust collaborative award for the Neuroscience in Psychiatry Network. A.F.A.-B. was supported by NIMH K08MH120564. Data were curated and analysed using a computational facility funded by an MRC research infrastructure award (MR/M009041/1) to the School of Clinical Medicine, University of Cambridge and supported by the mental health theme of the NIHR Cambridge Biomedical Research Centre.

Lack of diversity regarding genetic and environmental backgrounds weakens the generalization and clinical applicability of research findings on psychotic disorders. Notably, Latin Americans have been generally neglected in genetic studies, comprising less than 2% of genome-wide association study samples. But Latin American populations represent a unique opportunity for research, given the exceptionally high ethnic admixture of this group. Increasing genetic diversity is essential to improve the fine mapping of known regions associated with psychotic disorders, discover novel genetic associations, and replicate studies. Additionally, Latin America is characterized by massive social, political, and economic inequalities, all known risk factors for mental health issues, including psychotic disorders. This article aims to 1) discuss the challenges and advantages of studying Latin America’s particular genetic makeup and environmental context; 2) review previous studies conducted in the region; and 3) describe three Latin American research initiatives in progress: the Neuropsychiatric Genetics of Psychosis in Mexican Populations (NeuroMEX), the Paisa, and the Latin American Network for the Study of Early Psychosis (ANDES) studies.

The ability to identify biomarkers of psychosis risk is essential in defining effective preventive measures to potentially circumvent the transition to psychosis. Using samples of people at clinical high risk for psychosis (CHR) and Healthy controls (HC) who were administered a task fMRI paradigm, we used a framework for labelling time windows of fMRI scans as ‘integrated’ FC networks to provide a granular representation of functional connectivity (FC). Periods of integration were defined using the ‘cartographic profile’ of time windows and k‐means clustering, and sub‐network discovery was carried out using Network Based Statistics (NBS). There were no network differences between CHR and HC groups. Within the CHR group, using integrated FC networks, we identified a sub‐network negatively associated with longitudinal changes in the severity of psychotic symptoms. This sub‐network comprised brain areas implicated in bottom‐up sensory processing and in integration with motor control, suggesting it may be related to the demands of the fMRI task. These data suggest that extracting integrated FC networks may be useful in the investigation of biomarkers of psychosis risk., A framework for extracting epochs of integrated functional connectivity was used to test network differences between healthy control and clinical high‐risk (CHR) groups, as well as associations with longitudinal changes in symptom and functioning scores in CHR participants. A sub‐network suggestive of bottom‐up sensory processing was found to be associated with changes in positive psychotic symptoms in the CHR group. We suggest this to be a useful approach in searching for network‐based biomarkers of psychosis risk.

SummaryBackgroundSocial and environmental factors such as poverty or violence modulate the risk and course of schizophrenia. However, how they affect the brain in patients with psychosis remains unclear.AimsWe studied how environmental factors are related to brain structure in patients with schizophrenia and controls in Latin America, where these factors are large and unequally distributed.MethodThis is a multicentre study of magnetic resonance imaging in patients with schizophrenia and controls from six Latin American cities. Total and voxel-level grey matter volumes, and their relationship with neighbourhood characteristics such as average income and homicide rates, were analysed with a general linear model.ResultsA total of 334 patients with schizophrenia and 262 controls were included. Income was differentially related to total grey matter volume in both groups (P = 0.006). Controls showed a positive correlation between total grey matter volume and income (R = 0.14, P = 0.02). Surprisingly, this relationship was not present in patients with schizophrenia (R = −0.076, P = 0.17). Voxel-level analysis confirmed that this interaction was widespread across the cortex. After adjusting for global brain changes, income was positively related to prefrontal cortex volumes only in controls. Conversely, the hippocampus in patients with schizophrenia, but not in controls, was relatively larger in affluent environments. There was no significant correlation between environmental violence and brain structure.ConclusionsOur results highlight the interplay between environment, particularly poverty, and individual characteristics in psychosis. This is particularly important for harsh environments such as low- and middle-income countries, where potentially less brain vulnerability (less grey matter loss) is sufficient to become unwell in adverse (poor) environments.

Objective: 22q11.2 deletion syndrome (22q11DS) is among the strongest known genetic risk factors for schizophrenia. Previous studies have reported variable alterations in subcortical brain structures in 22q11DS. To better characterize subcortical alterations in 22q11DS, including modulating effects of clinical and genetic heterogeneity, the authors studied a large multicenter neuroimaging cohort from the ENIGMA 22q11.2 Deletion Syndrome Working Group. Methods: Subcortical structures were measured using harmonized protocols for gross volume and subcortical shape morphometry in 533 individualswith 22q11DS and 330matched healthy control subjects (age range, 6-56 years; 49% female). Results: Compared with the control group, the 22q11DS group showed lower intracranial volume (ICV) and thalamus, putamen, hippocampus, and amygdala volumes and greater lateral ventricle, caudate, and accumbens volumes (Cohen's d values, 20.90 to 0.93). Shape analysis revealed complex differences in the 22q11DS group across all structures. The larger A-D deletion was associated with more extensive shape alterations compared with the smaller A-B deletion. Participants with 22q11DS with psychosis showed lower ICV and hippocampus, amygdala, and thalamus volumes (Cohen's d values, 20.91 to 0.53) compared with participants with 22q11DS without psychosis. Shape analysis revealed lower thickness and surface area across subregions of these structures. Compared with subcortical findings from other neuropsychiatric disorders studied by the ENIGMA consortium, significant convergence was observed between participants with 22q11DS with psychosis and participants with schizophrenia, bipolar disorder, major depressive disorder, and obsessive-compulsive disorder. Conclusions: In the largest neuroimaging study of 22q11DS to date, the authors found widespread alterations to subcortical brain structures, which were affected by deletion size and psychotic illness. Findings indicate significant overlap between 22q11DS-associated psychosis, idiopathic schizophrenia, and other severe neuropsychiatric illnesses.

BackgroundCognition heavily relies on social determinants and genetic background. Latin America comprises approximately 8% of the global population and faces unique challenges, many derived from specific demographic and socioeconomic variables, such as violence and inequality. While such factors have been described to influence mental health outcomes, no large-scale studies with Latin American population have been carried out. Therefore, we aim to describe the cognitive performance of a representative sample of Latin American individuals with schizophrenia and its relationship to clinical factors. Additionally, we aim to investigate how socioeconomic status (SES) relates to cognitive performance in patients and controls.MethodsWe included 1175 participants from five Latin American countries (Argentina, Brazil, Chile, Colombia, and Mexico): 864 individuals with schizophrenia and 311 unaffected subjects. All participants were part of projects that included cognitive evaluation with MATRICS Consensus Cognitive Battery and clinical assessments.ResultsPatients showed worse cognitive performance than controls across all domains. Age and diagnosis were independent predictors, indicating similar trajectories of cognitive aging for both patients and controls. The SES factors of education, parental education, and income were more related to cognition in patients than in controls. Cognition was also influenced by symptomatology.ConclusionsPatients did not show evidence of accelerated cognitive aging; however, they were most impacted by a lower SES suggestive of deprived environment than controls. These findings highlight the vulnerability of cognitive capacity in individuals with psychosis in face of demographic and socioeconomic factors in low- and middle-income countries.

The fractional amplitude of low-frequency fluctuations (fALFFs) of the BOLD signal have been successfully applied as exploratory tools in neuroimaging. This metric has been useful in mapping brain functional changes in many clinical populations. However, little is known about the neurophysiological correlates of fALFF. This study aimed at demonstrating that fALFF is related to local network centrality during childhood and adolescence. The establishment of this relationship is fundamental to provide a more meaningful explanation to previous clinical and neurodevelopmental studies based on fALFF. Our findings show a correlation of ∼0.5 between these two metrics at a group level, which is a finding replicated in four large independent samples. However, when considering the across-subject and intra-subject correlations between the two metrics, the correlation is much lower, probably due to the low signal-to-noise ratio. Moreover, we found that regions with high fALFF and degree centrality overlapped modestly, particularly the posterior cingulate/precuneus and lateral parietal cortices.

Attention Deficit/Hyperactive Disorder (ADHD) is diagnosed based on observed behavioral outcomes alone. Given that some brain attentional networks involve circuits that control the eye pupil, we monitored pupil size in ADHD- diagnosed children and also in control children during a visuospatial working memory task. We present here the full dataset, consisting of pupil size time series for each trial and subject. There are data from, 22 control, and 28 ADHD-diagnosed children. There are also data from a subset of 17 ADHD children that performed the task twice, on- and off-medication. In addition, our dataset also includes gaze position data from each trial and subject, and also scores from the Weschler Intelligence Scale for Children. In this context, the dataset can serve as a resource to analyze dynamic eye movement and pupil changes as a function of known behavioral changes and scores in neuropsychological tests, which reflect neurocognitive processing., Design Type(s)repeated measure design • parallel group design • disease detection/diagnosis objectiveMeasurement Type(s)pupil size traitTechnology Type(s)eye tracking deviceFactor Type(s)experimental condition • age • biological sex • MedicationSample Characteristic(s)Homo sapiens • eye Machine-accessible metadata file describing the reported data (ISA-Tab format)

Previous research has shown that the autonomic nervous system provides essential constraints over ongoing cognitive function. However, there is currently a relative lack of direct empirical evidence for how this interaction manifests in the brain at the macroscale level. Here, we examine the role of ascending arousal and attentional load on large-scale network dynamics by combining pupillometry, functional MRI, and graph theoretical analysis to analyze data from a visual motion-tracking task with a parametric load manipulation. We found that attentional load effects were observable in measures of pupil diameter and in a set of brain regions that parametrically modulated their BOLD activity and mesoscale network-level integration. In addition, the regional patterns of network reconfiguration were correlated with the spatial distribution of the α2a adrenergic receptor. Our results further solidify the relationship between ascending noradrenergic activity, large-scale network integration, and cognitive task performance., Author Summary In our daily lives, it is usual to encounter highly demanding cognitive tasks. They have been traditionally regarded as challenges that are solved mainly through cerebral activity, specifically via information-processing steps carried by neurons in the cerebral cortex. Activity in cortical networks thus constitutes a key factor for improving our understanding of cognitive processes. However, recent evidence has shown that evolutionary older players in the central nervous system, such as brain stem’s ascending modulatory systems, might play an equally important role in diverse cognitive mechanisms. Our article examines the role of the ascending arousal system on large-scale network dynamics by combining pupillometry, functional MRI, and graph theoretical analysis.

Introduction Little is known about predictors of clinical response to clozapine treatment in treatment-resistant psychosis. Most published cohorts are small, providing inconsistent results. We aimed to identify baseline clinical predictors of future clinical response in patients who initiate clozapine treatment, mainly focusing on the effect of age, duration of illness, baseline clinical symptoms and homelessness. Methodology Retrospective cohort of patients with treatment-resistant schizophrenia, aged between 15 and 60 years, that initiated clozapine between 2014 and 2017. Sociodemographic characteristics, years from illness diagnosis, and clinical presentation before the initiation of clozapine were collected and analyzed. All-cause discontinuation at two years follow-up was used as the primary measure of clozapine response. Results 261 patients were included with a median age at illness diagnosis of 23 years old (IQR 19-29) and a median age at clozapine initiation of 25 (IQR: 21–33). 72.33% (183/253) continued clozapine after two years follow-up. Being homeless was associated to higher clozapine non-adherence, with an OR of 2.78 (95%CI 1.051–7.38) (p = 0.039, controlled by gender). Older age at clozapine initiation and longer delay from first schizophrenia diagnosis to clozapine initiation were also associated with higher clozapine non-adherence, with each year increasing the odds of discontinuation by 1.043 (95%CI 1.02–1.07; p = 0.001) and OR 1.092 (95%CI 1.01–1.18;p = 0.032) respectively. Conclusion Starting clozapine in younger patients or shortly after schizophrenia diagnosis were associated with better adherence.

BackgroundPreclinical models propose that the onset of psychosis involves increased hippocampal activity which drives subcortical dopaminergic dysfunction. We used multi-modal neuroimaging to examine the relationship between hippocampal regional cerebral blood flow (rCBF) and striatal dopamine synthesis capacity in people at clinical high risk (CHR) for psychosis, and investigated its association with subsequent clinical outcomes.MethodsNinety-five participants (67 CHR and 28 healthy controls) underwent pseudo-continuous arterial spin labelling and 18F-DOPA PET imaging at baseline. Clinical outcomes in CHR participants were determined after a median of 15 months follow-up, using the Comprehensive Assessment of At Risk Mental States (CAARMS) and the Global Assessment of Function (GAF) scale.ResultsCHR participants with a poor functional outcome (follow-up GAFInterpretationThese findings indicate that altered interactions between the hippocampus and the subcortical dopamine system are implicated in the pathophysiology of psychosis-related outcomes.

Background: Cannabis use among young people in Chile has increased significantly in the last years. There is a consistent link between cannabis and psychosis. Aim: To compare cannabis use in patients with a first episode of psychosis and healthy controls. Material and Methods: We included 74 patients aged 20 ± 3 years (78% males) admitted to hospital with a first episode of psychosis and a group of 60 healthy controls aged 23 ± 4 years (63% males). Cannabis consumption was assessed, including age of first time use and length of regular use. Results: Patients with psychosis reported a non-significantly higher frequency of life-time cannabis use. Patients had longer periods of regular cannabis use compared with healthy subjects (Odds ratio [OR] 2.4; 95% confi-dence intervals [CI] 1.14-5.05). Patients also used cannabis for the first time at an earlier age (16 compared with 17 years, p < 0.0). The population attributable fraction for regular cannabis use associated with hospital admissions due to psychosis was 17.7% (95% CI 1.2-45.5%). Conclusions: Cannabis use is related to psychosis in this Chilean group of patients. This relationship is stronger in patients with early exposure to the drug and longer the regular use. One of every five admissions due to psychosis is associated with cannabis consumption. These data should influence cannabis legisla-tion and the public policies currently being discussed in Chile.

Previous studies have suggested that subjects participating in schizophrenia research are not representative of the demographics of the global population of people with schizophrenia, particularly in terms of gender and geographical location. We here explored if this has evolved throughout the decades, examining changes in geographical location, gender and age of participants in studies of schizophrenia published in the last 50 years. We examined this using a meta-analytical approach on an existing database including over 3,000 studies collated for another project. We found that the proportion of studies and participants from low-and-middle income countries has significantly increased over time, with considerable input from studies from China. However, it is still low when compared to the global population they represent. Women have been historically under-represented in studies, and still are in high-income countries. However, a significantly higher proportion of female participants have been included in studies over time. The age of participants included has not changed significantly over time. Overall, there have been improvements in the geographical and gender representation of people with schizophrenia. However, there is still a long way to go so research can be representative of the global population of people with schizophrenia, particularly in geographical terms.

BackgroundResistance to antipsychotic treatment affects up to 30% of patients with schizophrenia. Although the time course of development of treatment-resistant schizophrenia (TRS) varies from patient to patient, the reasons for these variations remain unknown. Growing evidence suggests brain dysconnectivity as a significant feature of schizophrenia. In this study, we compared fractional anisotropy (FA) of brain white matter between TRS and non–treatment-resistant schizophrenia (non-TRS) patients. Our central hypothesis was that TRS is associated with reduced FA values.MethodsTRS was defined as the persistence of moderate to severe symptoms after adequate treatment with at least two antipsychotics from different classes. Diffusion-tensor brain MRI obtained images from 34 TRS participants and 51 non-TRS. Whole-brain analysis of FA and axial, radial, and mean diffusivity were performed using Tract-Based Spatial Statistics (TBSS) and FMRIB’s Software Library (FSL), yielding a contrast between TRS and non-TRS patients, corrected for multiple comparisons using family-wise error (FWE) ResultsWe found a significant reduction in FA in the splenium of corpus callosum (CC) in TRS when compared to non-TRS. The antipsychotic dose did not relate to the splenium CC.ConclusionOur results suggest that the focal abnormality of CC may be a potential biomarker of TRS.

BackgroundEvidence suggests the incidence of non-affective psychotic disorders (NAPDs) varies across persons and places, but data from the Global South is scarce. We aimed to estimate the treated incidence of NAPD in Chile, and variance by person, place and time.MethodsWe used national register data from Chile including all people, 10–65 years, with the first episode of NAPD (International Classification of Diseases, Tenth Revision: F20–F29) between 1 January 2005 and 29 August 2018. Denominators were estimated from Chilean National Census data. Our main outcome was treated incidence of NAPD and age group, sex, calendar year and regional-level population density, multidimensional poverty and latitude were exposures of interest.ResultsWe identified 32 358 NAPD cases [12 136 (39.5%) women; median age-at-first-contact: 24 years (interquartile range 18–39 years)] during 171.1 million person-years [crude incidence: 18.9 per 100 000 person-years; 95% confidence interval (CI) 18.7–19.1]. Multilevel Poisson regression identified a strong age–sex interaction in incidence, with rates peaking in men (57.6 per 100 000 person-years; 95% CI 56.0–59.2) and women (29.5 per 100 000 person-years; 95% CI 28.4–30.7) between 15 and 19 years old. Rates also decreased (non-linearly) over time for women, but not men. We observed a non-linear association with multidimensional poverty and latitude, with the highest rates in the poorest regions and those immediately south of Santiago; no association with regional population density was observed.ConclusionOur findings inform the aetiology of NAPDs, replicating typical associations with age, sex and multidimensional poverty in a Global South context. The absence of association with population density suggests this risk may be context-dependent.

Aim The evidence of the effectiveness and cost-effectiveness of early intervention for psychosis (EIP) services has motivated their implementation worldwide. However, complex interventions of such EIP services require local adaptations to successfully match population needs and cultural differences. Latin America is a heterogenous region where EIP services are progressively being adopted. Our aim is to map such initiatives in the region with a focus on implementation outcomes. Methods A scoping review following the Preferred Reporting Items for Systematic review and Meta-Analysis extension for Scoping Reviews guidelines was conducted. International and regional databases were searched for publications describing EIP programmes in the region. Besides mapping the services, we described implementation outcomes based on the Standards for Reporting Implementation Studies Checklist. Results Ten articles describing seven EIP initiatives from the region were found. Four countries were represented: Argentina, Brazil, Chile and Mexico. The implementation outcomes reporting was heterogenous, although it was possible to ascertain EIP services are feasible and adequate for the region's context. Also, there is some evidence of effectiveness in terms of reducing hospitalizations and improving symptoms. Information about fidelity measures was scarce and there was no information about costs or cost-effectiveness. Conclusions Only a small proportion of Latin American countries have adopted EIP services. Although these programmes seem to be feasible and effective, data on other implementation outcomes, such as fidelity, cultural appropriateness, cost-effectiveness and affordability are not available. This might in part explain why this effective approach has not been yet scaled-up at nationwide levels.

Resting-state functional MRI activity is organized as a complex network. However, this coordinated brain activity changes with time, raising questions about its evolving temporal arrangement. Does the brain visit different configurations through time in a random or ordered way? Advances in this area depend on developing novel paradigms that would allow us to shed light on these issues. We here propose to study the temporal changes in the functional connectome by looking at transition graphs of network activity. Nodes of these graphs correspond to brief whole-brain connectivity patterns (or meta-states), and directed links to the temporal transition between consecutive meta-states. We applied this method to two datasets of healthy subjects (160 subjects and a replication sample of 54), and found that transition networks had several non-trivial properties, such as a heavy-tailed degree distribution, high clustering, and a modular organization. This organization was implemented at a low biological cost with a high cost-efficiency of the dynamics. Furthermore, characteristics of the subjects’ transition graphs, including global efficiency, local efficiency and their transition cost, were correlated with cognition and motor functioning. All these results were replicated in both datasets. We conclude that time-varying functional connectivity patterns of the brain in health progress in time in a highly organized and complex order, which is related to behavior.

SummaryHuman brain structure changes throughout our lives. Altered brain growth or rates of decline are implicated in a vast range of psychiatric, developmental, and neurodegenerative diseases. Here, we identified common genetic variants that affect rates of brain growth or atrophy, in the first genome-wide association meta-analysis of changes in brain morphology across the lifespan. Longitudinal MRI data from 15,640 individuals were used to compute rates of change for 15 brain structures. The most robustly identified genesGPR139, DACH1andAPOEare associated with metabolic processes. We demonstrate global genetic overlap with depression, schizophrenia, cognitive functioning, insomnia, height, body mass index and smoking. Gene-set findings implicate both early brain development and neurodegenerative processes in the rates of brain changes. Identifying variants involved in structural brain changes may help to determine biological pathways underlying optimal and dysfunctional brain development and ageing.

Background: Multiple sclerosis exhibits specific neuropathological phenomena driving to both global and regional brain atrophy. At the clinical level, the disease is related to functional decline in cognitive domains as the working memory, processing speed, and verbal fluency. However, the compromise of social-cognitive abilities has concentrated some interest in recent years despite the available evidence suggesting the risk of disorganization in social life. Recent studies have used the MiniSEA test to assess the compromise of social cognition and have found relevant relationships with memory and executive functions, as well as with the level of global and regional brain atrophy. Objective: The present article aimed to identify structural changes related to socio-cognitive performance in a sample of patients with relapsing-remitting multiple sclerosis. Methods: 68 relapsing-remitting multiple sclerosis Chilean patients and 50 healthy control subjects underwent MRI scans and neuropsychological evaluation including social-cognition tasks. Total brain, white matter, and gray matter volumes were estimated. Also, voxel-based morphometry was applied to evaluate regional structural changes. Results: Patients exhibited lower scores in all neuropsychological tests. Social cognition exhibited a significant decrease in this group mostly related to the declining social perception. Normalized brain volume and white matter volume were significantly decreased when compared to healthy subjects. The regional brain atrophy analysis showed that changes in the insular cortex and medial frontal cortices are significantly related to the variability of social-cognitive performance among patients. Conclusions: In the present study, social cognition was only correlated with the deterioration of verbal fluency, despite the fact that previous studies have reported its link with memory and executive functions. The identification of specific structural correlates supports the comprehension of this phenomenon as an independent source of cognitive disability in these patients. RESUMEN Antecedentes: La esclerosis múltiple presenta fenómenos neuropatológicos específicos que conducen a la atrofia cerebral global y regional. A nivel clínico, la enfermedad está relacionada con el deterioro funcional de los dominios cognitivos como la memoria de trabajo, la velocidad de procesamiento y la fluidez verbal. Sin embargo, el compromiso de las habilidades socio-cognitivas ha concentrado cierto interés en los últimos años debido a la evidencia disponible que sugiere el riesgo de desorganización en la vida social. Estudios recientes han utilizado la prueba MiniSEA para evaluar el compromiso de la cognición social y han encontrado relaciones relevantes con la memoria y funciones ejecutiva, así como con el nivel de atrofia cerebral global y regional. Objetivo: El presente artículo tiene como objetivo identificar cambios estructurales relacionados con el rendimiento sociocognitivo en una muestra de pacientes con esclerosis múltiple recurrente-remitente. Métodos: 68 pacientes Chilenos con esclerosis múltiple recurrente-remitente y 50 sujetos de control sanos se sometieron a resonancias magnéticas y evaluación neuropsicológica, incluidas las tareas de cognición social. Se estimaron los volúmenes cerebrales totales, de materia blanca y materia gris. Además, se aplicó la morfometría basada en vóxel para evaluar los cambios estructurales regionales. Resultados: Los pacientes muestran puntuaciones más bajas en todas las pruebas neuropsicológicas. La cognición social exhibe una disminución significativa en este grupo principalmente relacionada con la disminución de la percepción social. El volumen normalizado del cerebro y el volumen de la materia blanca disminuyeron significativamente en comparación con los sujetos sanos. El análisis regional de atrofia cerebral mostró que los cambios en la corteza insular y la corteza frontal medial están significativamente relacionados con la variabilidad del rendimiento sociocognitivo entre los pacientes. Conclusiones: En el presente estudio, la cognición social sólo se correlacionó con el deterioro de la fluencia verbal, a pesar de que estudios previos han reportado su vinculación con la memoria y funciones ejecutivas. La identificación de correlatos estructurales específicos apoya la comprensión de este fenómeno como una fuente independiente de discapacidad cognitiva en estos pacientes.

Despues de varias decadas de desarrollo de los farmacos antipsicoticos, la esquizofrenia sigue siendo en gran medida una enfermedad cronica con muchos pacientes que experimentan una mala calidad de vida. En este contexto, la aparicion de los llamados antipsicoticos de segunda generacion fue recibida con gran entusiasmo. Los clinicos esperaban que los nuevos antipsicoticos causaran no solamente menos efectos secundarios motores que los mas antiguos, tal como la clorpromazina, sino tambien que mejoraran los sintomas y la funcionalidad general de los pacientes. Este articulo, de caracter narrativo, revisa como inicialmente la evidencia de un gran numero de ensayos controlados aleatorios parecio favorecer muchas de estas suposiciones. Esta vision, sin embargo, no era universal, y algunos investigadores destacaron el potencial efecto del diseno de los estudios en los resultados. Un aspecto importante dice relacion con la dosis utilizada de antipsicoticos de primera generacion, siendo aquellos ensayos que usaron mayores dosis los que apoyaron el uso de antipsicoticos de segunda generacion. Esta controversia se resolvio despues de la publicacion de tres estudios a gran escala, que incluian pacientes menos seleccionados y que enfocaban los resultados a largo plazo en un entorno clinico mas "tipico", los cuales no encontraron diferencias significativas entre los dos tipos de antipsicoticos. Desde entonces, las discusiones sobre la eleccion de los antipsicoticos han girado en torno a otros factores tales como los efectos secundarios, mas que en su capacidad para controlar los sintomas.

Background Social and environmental factors such as poverty or violence, modulate the risk and course of schizophrenia, but how they affect the brain in patients with psychosis remains unclear. We here studied how they are related to brain structure in schizophrenia and healthy controls in Latin America, where these factors are large and unequally distributed. Methods This is an MRI multi-center study in patients with schizophrenia and healthy controls from six Latin American cities: Buenos Aires, Medellin, Mexico City, Santiago, Sao Paulo and Porto Alegre. Total and voxel-level gray matter volumes obtained from T1-weighted MRI images and their relationship with income and homicide rates were analyzed using a general linear model. Results 334 patients with schizophrenia and 262 controls were included. Income was differentially related to total gray matter volume in the two groups (P=0.006). Controls showed a positive correlation between total gray matter volume and income (R=0.14, P=0.02). Surprisingly, this relationship was not present in schizophrenia (R=-0.076, P=0.17). Voxel-level analysis confirmed that this interaction was widespread across the cortex. After adjusting for global brain changes, income was positively related to prefrontal cortex volumes only in controls. Conversely, the hippocampus in patients, but not in controls, was relatively larger in affluent environments. There was no significant correlation between environmental violence and brain structure. Discussion Our results highlight the interplay between the environment, particularly poverty, and individual characteristics in psychosis. This is particularly important for harsh environments such as those from low and middle-income countries: potentially less brain vulnerability (less gray matter loss) is sufficient to become unwell in adverse (poor) environments. The development of algorithms exploring clinically-useful information from structural brain images in psychosis should include representative samples from low and middle-income countries.

The neuroimaging literature provides compelling evidence for functional dysconnectivity in people with psychosis. However, it is likely that at least some of the observed alterations represent secondary effects of illness chronicity and/or antipsychotic medication. In addition, the extent to which these alterations are specific to psychosis or represent a transdiagnostic feature of psychiatric illness remains unclear. The aim of this study was therefore to examine the diagnostic specificity of functional dysconnectivity in drug-naïve first-episode psychosis (FEP). We used resting-state functional magnetic resonance imaging and functional connectivity analysis to estimate network-level connectivity in 50 patients with FEP, 50 patients with major depressive disorder (MDD), 50 patients with post-traumatic stress disorder (PTSD), and 122 healthy controls (HCs). The FEP, MDD, and PTSD groups showed reductions in intranetwork connectivity of the default mode network relative to the HC group (p

Systematic information about Latino clozapine users is still scarce. Our aim was to evaluate the risk of clozapine-associated neutropenia in a Chilean cohort using the last Food and Drug Administration's recommendations for clozapine monitoring. Findings should improve clinical practice and promote changes in clozapine guidelines in Latin America. We conducted a retrospective observational study of 5380 Chilean clozapine users that started clozapine treatment between 2003 and 2015. The absolute risk of severe neutropenia was 0.61% (33/5380) with an incidence of 0.086 cases per 100 person-years of follow-up. 87.9% of cases with severe neutropenia appeared during first 18 weeks. Cases of mild neutropenia were 3.9% of total sample and occurred almost constantly without a specific risk time. 77.5% of cases of moderate or severe neutropenia didn't present an event of mild neutropenia before. 22.8% of clozapine users (1227/5380) discontinued treatment for any cause and 4.2% (225/5380) due to neutropenia in any severity level. Clozapine-associated neutropenia risk in Latino users is similar than in the rest of the world. The evidence of a very low risk for severe neutropenia and the behaviour of mild neutropenia cases confirm the feasibility of changes in Latin American clozapine guidelines using current Food and Drug Administration's recommendations as a model.

A mechanistic understanding of the pathology of psychiatric disorders has been hampered by extensive heterogeneity in biology, symptoms, and behavior within diagnostic categories that are defined subjectively. We investigated whether leveraging individual differences in information-processing impairments in patients with post-traumatic stress disorder (PTSD) could reveal phenotypes within the disorder. We found that a subgroup of patients with PTSD from two independent cohorts displayed both aberrant functional connectivity within the ventral attention network (VAN) as revealed by functional magnetic resonance imaging (fMRI) neuroimaging and impaired verbal memory on a word list learning task. This combined phenotype was not associated with differences in symptoms or comorbidities, but nonetheless could be used to predict a poor response to psychotherapy, the best-validated treatment for PTSD. Using concurrent focal noninvasive transcranial magnetic stimulation and electroencephalography, we then identified alterations in neural signal flow in the VAN that were evoked by direct stimulation of that network. These alterations were associated with individual differences in functional fMRI connectivity within the VAN. Our findings define specific neurobiological mechanisms in a subgroup of patients with PTSD that could contribute to the poor response to psychotherapy.

Social and environmental factors are known risk factors and modulators of mental health disorders. We here conducted a nonsystematic review of the neuroimaging literature studying the effects of poverty, urbanicity, and community violence, highlighting the opportunities of studying non-Western developing societies such as those in Latin America. Social and environmental factors in these communities are widespread and have a large magnitude, as well as an unequal distribution, providing a good opportunity for their characterization. Studying the effect of poverty in these settings could help to explore the brain effect of economic improvements, disentangle the effect of absolute and relative poverty, and characterize the modulating impact of poverty on the underlying biology of mental health disorders. Exploring urbanicity effects in highly unequal cities could help identify the specific factors that modulate this effect as well as examine a possible dose–response effect by studying megacities. Studying brain changes in those living among violence, which is particularly high in places such as Latin America, could help to characterize the interplay between brain predisposition and exposure to violence. Furthermore, exploring the brain in an adverse environment should shed light on the mechanisms underlying resilience. We finally provide examples of two methodological approaches that could contribute to this field, namely a big cohort study in the developing world and a consortium-based meta-analytic approach, and argue about the potential translational value of this research on the development of effective social policies and successful personalized medicine in disadvantaged societies. Fil: Crossley, Nicolas A.. Pontificia Universidad Católica de Chile; Chile Fil: Alliende, Luz Maria. Pontificia Universidad Católica de Chile; Chile Fil: Ossandon, Tomas. Pontificia Universidad Católica de Chile; Chile Fil: Castañeda, Carmen Paz. Instituto Psiquiátrico Dr. José Horwitz Barak; Chile Fil: González Valderrama, Alfonso. Instituto Psiquiátrico Dr. José Horwitz Barak; Chile. Universidad Finis Terrae.; Chile Fil: Undurraga, Juan. Universidad del Desarrollo; Chile. Instituto Psiquiátrico Dr. José Horwitz Barak; Chile Fil: Castro, Mariana Nair. Fundación para la Lucha contra las Enfermedades Neurológicas de la Infancia; Argentina. Universidad de Buenos Aires. Facultad de Medicina; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Guinjoan, Salvador Martín. Universidad de Buenos Aires. Facultad de Medicina; Argentina. Fundación para la Lucha contra las Enfermedades Neurológicas de la Infancia; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Díaz Zuluaga, Ana M.. Universidad de Antioquia; Colombia Fil: Pineda-Zapata, Julián A.. Instituto de Alta Tecnología Médica; Colombia Fil: López-Jaramillo, Carlos. Hospital Universitario San Vicente Fundación; Colombia. Universidad de Antioquia; Colombia Fil: Reyes Madrigal, Francisco. Instituto Nacional de Neurología y Neurocirugía; México Fil: León-Ortíz, Pablo. Instituto Nacional de Neurología y Neurocirugía; México Fil: de la Fuente-Sandoval, Camilo. Instituto Nacional de Neurología y Neurocirugía; México Fil: Czepielewski, Leticia Sanguinetti. Hospital de Clinicas de Porto Alegre; Brasil Fil: Gama, Clarissa S.. Hospital de Clinicas de Porto Alegre; Brasil Fil: Zugman, Andre. Universidade Federal de Sao Paulo; Brasil Fil: Gadelha, Ary. Universidade Federal de Sao Paulo; Brasil Fil: Jackowski, Andrea. Universidade Federal de Sao Paulo; Brasil Fil: Bressan, Rodrigo. Universidade Federal de Sao Paulo; Brasil

Background: Multiple Sclerosis produces changes in the functional connectivity of the brain. Resting-State fMRI is a useful tool for the study of functional changes in the human brain, and its metrics can be related to clinical findings involved in clinical decline. Social cognition has focused increasing interest because patients are exposed to experiencing social disorganization during the progression of the disease. fMRI has proved to be a useful tool for studying brain connectivity and its relation with social cognition both in resting-state and during socio-cognitive tasks. Objective. to identify functional changes during rest in Relapsing-Remitting Multiple Sclerosis patients and look for a correlation with social cognition. Methods. 45 patients with Relapsing-Remitting Multiple Sclerosis and 47 control subjects were recruited to perform a neuropsychological evaluation of the social cognition performance and to acquire resting-state fMRI. Results. Patients exhibited lower performance in social cognition tasks, mostly related to face emotion recognition. Decreased functional connectivity in patients is seen concerning the right anterior insula, middle frontal, and occipital regions while increased connectivity is mostly related to the occipital and visual areas. The connectivity of the fusiform cortex and the amygdala is related to the performance in emotion recognition and Theory of Mind tasks respectively. Conclusion. Social cognition compromise was found in this sample. Functional connectivity changes during rest were detected and correlated with social cognition changes in patients.

Functional brain hubs are key integrative regions in brain networks. Recently, brain hubs identified through resting-state fMRI have emerged as interesting targets to increase understanding of the relationships between large-scale functional networks and psychopathology. However, few studies have directly addressed the replicability and consistency of the hub regions identified and their association with symptoms. Here, we used the eigenvector centrality (EVC) measure obtained from graph analysis of two large, independent population-based samples of children and adolescents (7–15 years old; total N = 652; 341 subjects for site 1 and 311 for site 2) to evaluate the replicability of hub identification. Subsequently, we tested the association between replicable hub regions and psychiatric symptoms. We identified a set of hubs consisting of the anterior medial prefrontal cortex and inferior parietal lobule/intraparietal sulcus (IPL/IPS). Moreover, lower EVC values in the right IPS were associated with psychiatric symptoms in both samples. Thus, low centrality of the IPS was a replicable sign of potential vulnerability to mental disorders in children. The identification of critical and replicable hubs in functional cortical networks in children and adolescents can foster understanding of the mechanisms underlying mental disorders.

Abnormal brain connectivity or network dysfunction has been suggested as a paradigm to understand several psychiatric disorders. We here review the use of novel meta-analytic approaches in neuroscience that go beyond a summary description of existing results by applying network analysis methods to previously published studies and/or publicly accessible databases. We define this strategy of combining connectivity with other brain characteristics as ‘meta-connectomics’. For example, we show how network analysis of task-based neuroimaging studies has been used to infer functional co-activation from primary data on regional activations. This approach has been able to relate cognition to functional network topology, demonstrating that the brain is composed of cognitively specialized functional subnetworks or modules, linked by a rich club of cognitively generalized regions that mediate many inter-modular connections. Another major application of meta-connectomics has been efforts to link meta-analytic maps of disorder-related abnormalities or MRI ‘lesions’ to the complex topology of the normative connectome. This work has highlighted the general importance of network hubs as hotspots for concentration of cortical grey-matter deficits in schizophrenia, Alzheimer's disease and other disorders. Finally, we show how by incorporating cellular and transcriptional data on individual nodes with network models of the connectome, studies have begun to elucidate the microscopic mechanisms underpinning the macroscopic organization of whole-brain networks. We argue that meta-connectomics is an exciting field, providing robust and integrative insights into brain organization that will likely play an important future role in consolidating network models of psychiatric disorders.

Background Novel methods for measuring large-scale dynamic brain organisation are needed to provide new biomarkers of schizophrenia. Using a method for modelling dynamic modular organisation, previous evidence suggests higher ‘flexibility’ (switching between multilayer network communities) to be a feature of schizophrenia. Methods The current study compared flexibility between 55 patients with schizophrenia and 72 controls (the COBRE Dataset). In addition, novel methods of ‘between resting state network synchronisation’ (BRSNS) and the probability of transition from one community to another were used to further describe group differences in dynamic community structure. Results There was significantly higher schizophrenia group flexibility in cerebellar (F (1,124) = 9.33, p (FDR) = 0.017), subcortical (F (1,124) = 13.14, p (FDR) = 0.005), and fronto-parietal task control (F (1,124) = 7.19, p (FDR) = 0.033) resting state networks (RSNs), as well as in the left thalamus (MNI XYZ: -2, -13, 12; F(1, 124) = 17.1, p (FDR) < 0.001) and the right crus I (MNI XYZ: 35, -67, -34; F (1, 124) = 19.65, p (FDR) < 0.001). Flexibility in the left thalamus reflected transitions between communities covering default mode and sensory-somatomotor RSNs. BRSNS scores suggested altered dynamic inter-RSN modular configuration in schizophrenia. Discussion This study suggests higher flexibility in a schizophrenia group at an RSN and node level and provides novel methods of exploring dynamic community structure. Mediation of group differences by mean time window correlation did however suggest flexibility to be no better as a schizophrenia biomarker than simpler measures and a range of methodological choices affected results.

AIM Studies conducted in the United States have highlighted a higher prevalence of metabolic alterations (MA) in Latino population and Latino psychotic patients. Metabolic risk in psychosis is known to be present from initial stages of the disease. To better characterize this population, we explored the prevalence of MA and metabolic syndrome (MS) in early psychosis patients in a Latin American country. METHODS Transversal, observational study comparing the prevalence of MA and MS in patients with early psychosis from an outpatient program in Chile (n = 148) with a community representative sample from the 2009-2010 National Health Survey (n = 568). ANOVA and regression analysis were performed obtaining odds ratio for MA and MS. RESULTS The prevalence of MS was 44.7% in patients compared to 11.4% in the community sample (odds ratio [OR] 5.28, confidence interval [CI] 95% 3.07-9.08; P-value