Childhood trauma, brain structure and emotion recognition in patients with schizophrenia and healthy participants

A Systematic Review and Meta-Analysis of Social Cognition Among People Living with HIV: Implications for Non-Social Cognition and Social Everyday Functioning

Social cognition-the complex mental ability to perceive social stimuli and negotiate the social environment-has emerged as an important cognitive ability needed for social functioning, everyday functioning, and quality of life. Deficits in social cognition have been well documented in those with severe mental illness including schizophrenia and depression, those along the autism spectrum, and those with other brain disorders where such deficits profoundly impact everyday life. Moreover, subtle deficits in social cognition have been observed in other clinical populations, especially those that may have compromised non-social cognition (i.e., fluid intelligence such as memory). Among people living with HIV (PLHIV), 44% experience cognitive impairment; likewise, social cognitive deficits in theory of mind, prosody, empathy, and emotional face recognition/perception are gradually being recognized. This systematic review and meta-analysis aim to summarize the current knowledge of social cognitive ability among PLHIV, identified by 14 studies focused on social cognition among PLHIV, and provides an objective consensus of the findings. In general, the literature suggests that PLHIV may be at-risk of developing subtle social cognitive deficits that may impact their everyday social functioning and quality of life. The causes of such social cognitive deficits remain unclear, but perhaps develop due to (1) HIV-related sequelae that are damaging the same neurological systems in which social cognition and non-social cognition are processed; (2) stress related to coping with HIV disease itself that overwhelms one's social cognitive resources; or (3) may have been present pre-morbidly, possibly contributing to an HIV infection. From this, a theoretical framework is proposed highlighting the relationships between social cognition, non-social cognition, and social everyday functioning.

Adverse childhood experiences and cognition: A cross-sectional study in Xhosa people living with schizophrenia and matched medical controls

BACKGROUND

Adverse childhood experiences (ACEs) are associated with impaired cognitive function in adult life in the general population as well as in people living with schizophrenia (PLS). Research on cognitive function in PLS in low- and middle-income countries (LMIC) is, however, limited. The objectives of this study were to investigate the association between ACE types and various cognitive domains in a sample of PLS and matched medical controls, and to determine the moderating effect of group membership (PLS vs. medical controls) on these associations, in the South African setting.

METHODS

Participants (n PLS = 520; n medical controls = 832) completed the Childhood Trauma Questionnaire-Short Form, the Structured Clinical Interview for DSM-IV (SCID-I), and the University of Pennsylvania Computerized Neurocognitive Battery (PennCNB). An efficiency or speed score was used to assess performance across 9 cognitive domains. The association between exposure to different ACE types and 9 cognitive domains was examined using partial correlations and multiple linear regression models, adjusting for sex, age and education years. Finally, potential moderating effects of group membership (PLS vs. medical controls) on the association between ACEs and cognitive domains were tested.

RESULTS

In the entire sample, emotional and physical abuse predicted worse performance on sensorimotor and emotion identification domains. Also, emotional abuse was negatively associated with motor function, physical abuse was negatively associated with spatial processing, and physical neglect was negatively associated with face memory and emotion identification. In contrast, emotional neglect was related to better performance on abstraction and mental flexibility. No moderating effect of group membership was found on any of these associations.

CONCLUSION

Exposure to ACEs was associated with social and non-social cognition in adulthood, although the magnitude of these relationships was small and similar between PLS and matched medical controls. The nature of these associations differed across ACE subtype, suggesting the need for a nuanced approach to studying a range of mechanisms that may underlie different associations. However, a number of ACE subtypes were associated with worse performance on emotional identification, indicating that some underlying mechanisms may have more transversal impact. These findings contribute to the sparse body of literature on ACEs and cognition in PLS in LMIC.

Independent effects of early life adversity on social cognitive function in patients with schizophrenia

Objective

The aim of this study was to investigate the impact of early life adversity on cognitive function in patients with schizophrenia, with a focus on social cognition (SC).

Methods

Two groups of patients with schizophrenia were recruited and matched on sociodemographic and clinical characteristics. One group consisted of 32 patients with a history of childhood trauma (SCZ-ct), and the other group consisted of 30 patients without a history of childhood trauma (SCZ-nct). In addition, 39 healthy controls without a history of childhood trauma (HC-nct) were also recruited. The intelligence of the three groups was assessed using the Wechsler Abbreviated Scale of Intelligence (WAIS-RC) short version. The cognitive function evaluation was conducted using the MATRICS Consensus Cognitive Battery (MCCB), and early life adversity was measured using the Childhood Trauma Questionnaire-Short Form (CTQ) and Bullying Scale for Adults (BSA).

Results

Patients with schizophrenia endosed significantly higher scores on the CTQ (F=67.61, p<0.001) and BSA (F=9.84, p<0.001) compared to the HC-nct. Analysis of covariance (ANCOVA) and post-hoc analyses revealed that SCZ-ct (F=11.20, p<0.001) exhibited the most pronounced cognitive impairment among the three groups, as indicated in MCCB total scores and in the domain score of SC. CTQ exhibited a negative correlation with MCCB (r=-0.405, p< 0.001); SC was negatively correlated with physical abuse (PA) of CTQ (r=-0.271, p=0.030) and emotional abuse (EA) of BSA (r=-0.265, p=0.034) in the whole patient sample. Higher SC performance was significantly predicted by CT_total (Beta =-0.582, p<0.001, 95% CI -0.96-0.46), and years of education (Beta=0.260, p =0.014, 95% CI 0.20-1.75) in schizophrenia.

Conclusions

Besides familial trauma, schizophrenia patients appear to have a higher likelihood of experiencing bullying in their early life. These experiences seem to contribute significantly to their severe impairments in SC.

Corpus callosum microstructural organization mediates the effects of physical neglect on social cognition in schizophrenia

Exposure to early life adversity is associated with both increased risk of developing schizophrenia and poorer performance on measures of social cognitive functioning. In this study, we examined whether interleukin-6 (IL-6) and Corpus Callosum (CC) microstructure mediated the association between childhood physical neglect and social cognition. Fifty-eight patients with a diagnosis of schizophrenia were included. The CANTAB emotion recognition task (unbiased hit rate) was used to assess social cognition. We found that the microstructural organization of the CC significantly mediated the association between physical neglect and emotion recognition. Furthermore, in a sequential mediation analysis that also considered the role of inflammatory response, the association between physical neglect, and lower emotion recognition performance was sequentially mediated by higher IL-6 and lower fractional anisotropy of the CC. This mediating effect of IL-6 was only present when simultaneously considering the effects of CC microstructural organization and remained significant while controlling for the effects of sex, BMI and medication dosage (but not age). Overall, the findings suggest that the association between physical neglect and poorer emotion recognition in schizophrenia occurs, at least in part, via its association with white matter microstructure.

Genetic and inflammatory effects on childhood trauma and cognitive functioning in patients with schizophrenia and healthy participants

Recent studies have reported a negative association between exposure to childhood trauma, including physical neglect, and cognitive functioning in patients with schizophrenia. Childhood trauma has been found to influence immune functioning, which may contribute to the risk of schizophrenia and cognitive symptoms of the disorder. In this study, we aimed to test the hypothesis that physical neglect is associated with cognitive ability, and that this association is mediated by a combined latent measure of inflammatory response, and moderated by higher genetic risk for schizophrenia. The study included 279 Irish participants, comprising 102 patients and 177 healthy participants. Structural equation modelling was used to perform mediation and moderation analyses. Inflammatory response was measured via basal plasma levels of IL-6, TNF-α, and CRP, and cognitive performance was assessed across three domains: full-scale IQ, logical memory, and the emotion recognition task. Genetic variation for schizophrenia was estimated using a genome-wide polygenic score based on genome-wide association study summary statistics. The results showed that inflammatory response mediated the association between physical neglect and all measures of cognitive functioning, and explained considerably more variance than any of the inflammatory markers alone. Furthermore, genetic risk for schizophrenia was observed to moderate the direct pathway between physical neglect and measures of non-social cognitive functioning in both patient and healthy participants. However, genetic risk did not moderate the mediated pathway associated with inflammatory response. Therefore, we conclude that the mediating role of inflammatory response and the moderating role of higher genetic risk may independently influence the association between adverse early life experiences and cognitive function in patients and healthy participants.

Sexual abuse and psychotic phenomena: a directed acyclic graph analysis of affective symptoms using English national psychiatric survey data

BACKGROUND

Sexual abuse and bullying are associated with poor mental health in adulthood. We previously established a clear relationship between bullying and symptoms of psychosis. Similarly, we would expect sexual abuse to be linked to the emergence of psychotic symptoms, through effects on negative affect.

METHOD

We analysed English data from the Adult Psychiatric Morbidity Surveys, carried out in 2007 (N = 5954) and 2014 (N = 5946), based on representative national samples living in private households. We used probabilistic graphical models represented by directed acyclic graphs (DAGs). We obtained measures of persecutory ideation and auditory hallucinosis from the Psychosis Screening Questionnaire, and identified affective symptoms using the Clinical Interview Schedule. We included cannabis consumption and sex as they may determine the relationship between symptoms. We constrained incoming edges to sexual abuse and bullying to respect temporality.

RESULTS

In the DAG analyses, contrary to our expectations, paranoia appeared early in the cascade of relationships, close to the abuse variables, and generally lying upstream of affective symptoms. Paranoia was consistently directly antecedent to hallucinations, but also indirectly so, via non-psychotic symptoms. Hallucinosis was also the endpoint of pathways involving non-psychotic symptoms.

CONCLUSIONS

Via worry, sexual abuse and bullying appear to drive a range of affective symptoms, and in some people, these may encourage the emergence of hallucinations. The link between adverse experiences and paranoia is much more direct. These findings have implications for managing distressing outcomes. In particular, worry may be a salient target for intervention in psychosis.

The neural, stress hormone and inflammatory correlates of childhood deprivation and threat in psychosis: A systematic review

Childhood adversity increases the risk of developing psychosis, but the biological mechanisms involved are unknown. Disaggregating early adverse experiences into core dimensions of deprivation and threat may help to elucidate these mechanisms. We therefore systematically searched the literature investigating associations between deprivation and threat, and neural, immune and stress hormone systems in individuals on the psychosis spectrum. Our search yielded 74 articles, from which we extracted and synthesized relevant findings. While study designs were heterogeneous and findings inconsistent, some trends emerged. In psychosis, deprivation tended to correlate with lower global cortical volume, and some evidence supported threat-related variation in prefrontal cortex morphology. Greater threat exposure was also associated with higher C-reactive protein, and higher and lower cortisol measures. When examined, associations in controls were less evident. Overall, findings indicate that deprivation and threat may associate with partially distinct biological mechanisms in the psychosis spectrum, and that associations may be stronger than in controls. Dimensional approaches may help disentangle the biological correlates of childhood adversity in psychosis, but more studies are needed.

Pathways from threat exposure to psychotic symptoms in youth: The role of emotion recognition bias and brain structure

BACKGROUND

Research supports an association between threatening experiences in childhood and psychosis. It is possible that early threat exposure disrupts the development of emotion recognition (specifically, producing a bias for facial expressions relating to threat) and the brain structures subserving it, contributing to psychosis development.

METHODS

Using data from the Philadelphia Neurodevelopmental Cohort, we examined associations between threat exposure and both the misattribution of facial expressions to fear/anger in an emotion recognition task, and gray matter volumes in key emotion processing regions. Our sample comprised youth with psychosis spectrum symptoms (N = 304), control youth (N = 787), and to evaluate specificity, youth with internalizing symptoms (N = 92). The moderating effects of group and sex were examined.

RESULTS

Both the psychosis spectrum and internalizing groups had higher levels of threat exposure than controls. In the total sample, threat exposure was associated with lower left medial prefrontal cortex (mPFC) volume but not misattributions to fear/anger. The effects of threat exposure did not significantly differ by group or sex.

CONCLUSIONS

The findings of this study provide evidence for an effect of threat exposure on mPFC morphology, but do not support an association between threat exposure and a recognition bias for threat-related expressions, that is particularly pronounced in psychosis. Future research should investigate factors linking transdiagnostic alterations related to threat exposure with psychotic symptoms, and attempt to clarify the mechanisms underpinning emotion recognition misattributions in threat-exposed youth.

Examining associations, moderators and mediators between childhood maltreatment, social functioning, and social cognition in psychotic disorders: a systematic review and meta-analysis

Childhood maltreatment (CM) has been related to social functioning and social cognition impairment in people with psychotic disorders (PD); however, evidence across different CM subtypes and social domains remains less clear. We conducted a systematic review and meta-analysis to quantify associations between CM, overall and its different subtypes (physical/emotional/sexual abuse, physical/emotional neglect), and domains of social functioning and social cognition in adults with PD. We also examined moderators and mediators of these associations. A PRISMA-compliant systematic search was performed on 24 November 2022 (PROSPERO CRD42020175244). Fifty-three studies (N = 13 635 individuals with PD) were included in qualitative synthesis, of which 51 studies (N = 13 260) with 125 effects sizes were pooled in meta-analyses. We found that CM was negatively associated with global social functioning and interpersonal relations, and positively associated with aggressive behaviour, but unrelated to independent living or occupational functioning. There was no meta-analytic evidence of associations between CM and social cognition. Meta-regression analyses did not identify any consistent moderation pattern. Narrative synthesis identified sex and timing of CM as potential moderators, and depressive symptoms and maladaptive personality traits as possible mediators between CM and social outcomes. Associations were of small magnitude and limited number of studies assessing CM subtypes and social cognition are available. Nevertheless, adults with PD are at risk of social functioning problems after CM exposure, an effect observed across multiple CM subtypes, social domains, diagnoses and illness stages. Maltreated adults with PD may thus benefit from trauma-related and psychosocial interventions targeting social relationships and functioning.

Subcortical structures associated with childhood trauma and perceived stress in schizophrenia

BACKGROUND

Childhood trauma influences the clinical features of schizophrenia. In this study, we examined how childhood trauma and perceived stress are associated with clinical manifestations and subcortical gray matter volumes (GMVs) in patients with schizophrenia.

METHODS

We recruited 127 patients with schizophrenia and 83 healthy controls for assessment of early childhood trauma, perceived stress, and clinical symptoms. With structural brain imaging, we identified the GMVs of subcortical structures and examined the relationships between childhood trauma, perceived stress, clinical symptoms, and subcortical GMVs.

RESULTS

Compared to controls, patients with schizophrenia showed higher levels of childhood trauma and perceived stress. Patients with schizophrenia showed significantly smaller amygdala and hippocampus GMVs as well as total cortical GMVs than age-matched controls. Childhood trauma score was significantly correlated with the severity of clinical symptoms, depression, perceived stress, and amygdala GMVs. Perceived stress was significantly correlated with clinical symptoms, depression, and hippocampus and amygdala GMVs. Further, the association between childhood trauma (emotional neglect) and stress coping ability was mediated by right amygdala GMV in patients with schizophrenia.

CONCLUSIONS

Patients with schizophrenia had more exposure to early-life trauma and poorer stress coping. Both childhood trauma and perceived stress were associated with smaller amygdala volumes. The relationship between early-life trauma and perceived stress was mediated by right amygdala GMV in patients with schizophrenia. These findings together suggest the long-term effects of childhood trauma on perceived stress and the subcortical volumetric correlates of the effects in schizophrenia.

Adverse childhood experiences in patients with schizophrenia: related factors and clinical implications

The relationship between adverse childhood experiences (ACEs) and the development of psychotic symptoms is not well understood. Therefore, this study aimed to investigate the frequency and distribution of ACEs among patients with schizophrenia and their potential correlation with symptomatology and personality pathology. We conducted a cross-sectional study involving 571 patients with schizophrenia in Shanghai, China. Symptomatology was assessed using the Positive and Negative Symptoms Scale (PANSS) and personality pathology was assessed using the Personality Diagnostic Questionnaire Fourth Edition Plus (PDQ-4+). ACEs were assessed using the Child Trauma Questionnaire-Short Form (CTQ-SF). ACEs were highly prevalent, with 80.8% of the patients with schizophrenia reporting at least one ACE. The three most common types of ACE were physical neglect (69.8%), emotional neglect (28.2%), and emotional abuse (22.9%). For specific ACE, emotional abuse was significantly associated with PD traits, whereas emotional and physical neglect types of ACE was significantly associated with negative symptoms. A higher level of physical abuse was more commonly reported by men, younger individuals, and those with a higher level of antisocial PD traits. Higher levels of physical neglect were associated with more severe negative symptoms. ACEs are commonly observed in patients with schizophrenia. Therefore, it is strongly recommended that this clinical population be provided with a comprehensive assessment and individualized intervention for those exposed to specific ACEs.

Early life stress, low-grade systemic inflammation and weaker suppression of the default mode network (DMN) during face processing in Schizophrenia

Childhood trauma (CT) is associated with lower cognitive and social cognitive function in schizophrenia. Recent evidence suggests that the relationship between CT and cognition is mediated by both low-grade systemic inflammation and reduced connectivity of the default mode network (DMN) during resting state. This study sought to test whether the same pattern of associations was observed for DMN connectivity during task based activity. Fifty-three individuals with schizophrenia (SZ) or schizoaffective disorder (SZA) and one hundred and seventy six healthy participants were recruited from the Immune Response and Social Cognition (iRELATE) project. A panel of pro-inflammatory markers that included IL-6, IL-8, IL-10, tumour necrosis factor-alpha (TNFa), and C-reactive protein (CRP), were measured in plasma using ELISA. DMN connectivity was measured during an fMRI social cognitive face processing task. Patients showed evidence of low grade systemic inflammation and significantly increased connectivity between the left lateral parietal (LLP) cortex-cerebellum and LLP-left angular gyrus compared to healthy participants. Across the entire sample, IL-6 predicted increased connectivity between LLP-cerebellum, LLP-precuneus, and mPFC-bilateral-precentral-gyri and left postcentral gyrus. In turn, and again in the entire sample, IL-6 (but no other inflammatory marker) mediated the relationship between childhood physical neglect and LLP-cerebellum. Physical neglect scores also significantly predicted the positive association between IL-6 and LLP-precuneus connectivity. This is to our knowledge the first study that provides evidence that higher plasma IL-6 mediates the association between higher childhood neglect and increased DMN connectivity during task based activity. Consistent with our hypothesis, exposure to trauma is associated with weaker suppression of the DMN during a face processing task, and this association was mediated via increased inflammatory response. The findings may represent part of the biological mechanism by which CT and cognitive performance are related.

Intellectual performance correlates of trauma exposure in adolescent psychiatric inpatients

Half of individuals have experienced a trauma adequate to meet criteria for PTSD. Intelligence may correlate with trauma, with the causal direction unclear. The Childhood Trauma Questionnaire (CTQ) was administered to 733 child and adolescent inpatients. Intelligence and academic achievement was assessed using the Wechsler Scales. Clinician diagnoses came from the electronic medical record, as did data on exposure to substance abuse and other stressors. Multivariate analyses assessed associations between intelligence, diagnoses, experiences, and CTQ. Cases who met criteria for physical and sexual abuse performed more poorly across all intellectual domains. Other than for PTSD, there were no diagnostic differences in CTQ scores. Emotional abuse or neglect were not associated with intelligence, although exposure to substance abuse was associated with increased CTQ scores and lower intelligence. Exposure to substance abuse as a covariate did not eliminate the influence of CTQ scores on intelligence, but was consistently related to intelligence beyond CTQ scores. Intelligence and substance abuse are known to have genomic influences and recent studies have suggested a genomic signature associated with childhood abuse. Future genomic studies of the consequences of trauma exposure could add intelligence polygenic scores into their models, while considering genomic and nongenomic elements of family experiences.

Differential effects of parental socioeconomic status on cortical thickness in patients with schizophrenia spectrum disorders and healthy controls

OBJECTIVES

Widespread changes in cortical thickness (CT) have been repeatedly reported in schizophrenia (SZ). The nature of the pathophysiologic process underlying such changes remains to be elucidated. The aims of the present study were to measure the CT; evaluate parent socioeconomic status (pSES), childhood trauma (ChT) and premorbid adjustment (PA) in patients with schizophrenia spectrum disorders (SSDs); and investigate group differences in CT (i.e., SSD vs. healthy controls (HCs)), pSES, PA, and/or ChT, as well as the interactions among these factors.

METHODS

164 patients with SSD and 245 age-, sex- and education-matched healthy controls have participated. The pSES, ChT and PA were evaluated using Korean version of Polyenvironmental Risk Score, Early Trauma Inventory Self Report-Short Form and Premorbid Adjustment Scale, respectively. Vertex-wise measure of CT was estimated using the FreeSurfer. To investigate the main effects and interactions, multilevel regression was employed.

RESULTS

We found widespread cortical thinning in patients with SSDs compared to HCs. The cortical thinning was associated with ChT, symptom severity and chlorpromazine equivalent dose and duration of illness in patients. In multilevel regression, main effects of group and pSES and interaction between group and pSES were found whereas a significant interaction between ChT and CPZ equivalent was found in patients.

CONCLUSION

Our findings indicate that compared to HCs, patients with SSDs have cortical structural abnormalities, and that group and pSES interaction determines CT. Further studies are needed to explore the effects of psychosocial factors on brain structural and functional abnormalities in SZ.

The influence of childhood emotional neglect on emotional face processing in young adults

Childhood emotional neglect (CEN) refers to a failure to meet the basic emotional needs of a child, which can seriously impact interpersonal communication and psychological health in young adults. Emotional face processing is critical in interpersonal communication; however, whether CEN affects this processing in young adults has not been investigated. Therefore, the current study aimed to explore the effects of CEN on emotional face processing in young adults. Using the Child Trauma Questionnaire, an online survey was conducted with 5010 students from four universities in Tianjin, China. After online interviews and diagnosis by professional doctors, we obtained 20 participants with CEN (CEN group) and 20 without CEN (control group). None of the participants had any mental diseases. A 2 × 4 mixed design was used to investigate the differences in accuracy and response time when identifying the valence of the emotional faces. Compared to the control group, the CEN group identified the valence of all emotional faces more slowly, but there was no significant difference between the two groups in terms of accuracy. CEN caused delayed emotional face processing in young adults, which may be related to unresponsive, unavailable, and limited emotional interaction patterns between parents and their children.

Structural brain correlates of childhood trauma with replication across two large, independent community-based samples

INTRODUCTION

Childhood trauma and adversity are common across societies and have strong associations with physical and psychiatric morbidity throughout the life-course. One possible mechanism through which childhood trauma may predispose individuals to poor psychiatric outcomes is via associations with brain structure. This study aimed to elucidate the associations between childhood trauma and brain structure across two large, independent community cohorts.

METHODS

The two samples comprised (i) a subsample of Generation Scotland (n=1,024); and (ii) individuals from UK Biobank (n=27,202). This comprised n=28,226 for mega-analysis. MRI scans were processed using Free Surfer, providing cortical, subcortical, and global brain metrics. Regression models were used to determine associations between childhood trauma measures and brain metrics and psychiatric phenotypes.

RESULTS

Childhood trauma associated with lifetime depression across cohorts (OR 1.06 GS, 1.23 UKB), and related to early onset and recurrent course within both samples. There was evidence for associations between childhood trauma and structural brain metrics. This included reduced global brain volume, and reduced cortical surface area with highest effects in the frontal (β=-0.0385, SE=0.0048, p(FDR)=5.43x10-15) and parietal lobes (β=-0.0387, SE=0.005, p(FDR)=1.56x10-14). At a regional level the ventral diencephalon (VDc) displayed significant associations with childhood trauma measures across both cohorts and at mega-analysis (β=-0.0232, SE=0.0039, p(FDR)=2.91x10-8). There were also associations with reduced hippocampus, thalamus, and nucleus accumbens volumes.

DISCUSSION

Associations between childhood trauma and reduced global and regional brain volumes were found, across two independent UK cohorts, and at mega-analysis. This provides robust evidence for a lasting effect of childhood adversity on brain structure.

Developmental Manipulation-Induced Changes in Cognitive Functioning

Schizophrenia is a complex neurodevelopmental disorder with as-yet no identified cause. The use of animals has been critical to teasing apart the potential individual and intersecting roles of genetic and environmental risk factors in the development of schizophrenia. One way to recreate in animals the cognitive impairments seen in people with schizophrenia is to disrupt the prenatal or neonatal environment of laboratory rodent offspring. This approach can result in congruent perturbations in brain physiology, learning, memory, attention, and sensorimotor domains. Experimental designs utilizing such animal models have led to a greatly improved understanding of the biological mechanisms that could underlie the etiology and symptomology of schizophrenia, although there is still more to be discovered. The implementation of the Research and Domain Criterion (RDoC) has been critical in taking a more comprehensive approach to determining neural mechanisms underlying abnormal behavior in people with schizophrenia through its transdiagnostic approach toward targeting mechanisms rather than focusing on symptoms. Here, we describe several neurodevelopmental animal models of schizophrenia using an RDoC perspective approach. The implementation of animal models, combined with an RDoC framework, will bolster schizophrenia research leading to more targeted and likely effective therapeutic interventions resulting in better patient outcomes.

Bridging the Gap Between Environmental Adversity and Neuropsychiatric Disorders: The Role of Transposable Elements

Long regarded as “junk DNA,” transposable elements (TEs) have recently garnered much attention for their role in promoting genetic diversity and plasticity. While many processes involved in mammalian development require TE activity, deleterious TE insertions are a hallmark of several psychiatric disorders. Moreover, stressful events including exposure to gestational infection and trauma, are major risk factors for developing psychiatric illnesses. Here, we will provide evidence demonstrating the intersection of stressful events, atypical TE expression, and their epigenetic regulation, which may explain how neuropsychiatric phenotypes manifest. In this way, TEs may be the “bridge” between environmental perturbations and psychopathology.

Childhood Trauma Associations With the Interpersonal Psychological Theory of Suicide and Social Cognitive Biases in Psychotic Disorders

Childhood trauma (CT) is associated with suicidal ideation and behaviors (SI/SB) in people with psychosis. The interpersonal psychological theory of suicide (IPTS) suggests that there are four factors that increase suicide risk: thwarted belongingness, perceived burdensomeness, acquired capacity for suicide, and hopelessness. The IPTS constructs and social cognitive biases are associated with SI/SB in psychotic disorders. However, the role of CT in IPTS constructs and social cognitive biases has not been examined in psychosis. In an outpatient community sample of persons with psychotic disorders (N = 96) assessed with the Childhood Trauma Questionnaire, the aims of this study were to a) evaluate rates of CT in this sample, b) determine the relationship between CT types and lifetime SI/SB, and c) explore the relationship between CT types, IPTS constructs, and social cognitive biases. All participants reported experiencing CT. Emotional abuse was associated with greater SI severity and higher rates of lifetime suicide attempts, as well as with greater perceived burdensomeness and more severe negative social cognitive biases. Other CT types were minimally associated with SI/SB or IPST constructs; hopelessness was not associated. Overall, negative interpersonal beliefs and social cognitive biases may explain how CT increases suicide risk in psychosis.

Early life Adversity, functional connectivity and cognitive performance in Schizophrenia: The mediating role of IL-6

OBJECTIVE

Exposure to childhood trauma (CT) is associated with cognitive impairment in schizophrenia, and deficits in social cognition in particular. Here, we sought to test whether IL-6 mediated the association between CT and social cognition both directly, and sequentially via altered default mode network (DMN) connectivity.

METHODS

Three-hundred-and-eleven participants (104 patients and 207 healthy participants) were included, with MRI data acquired in a subset of n = 147. CT was measured using the childhood trauma questionnaire (CTQ). IL-6 was measured in both plasma and in toll like receptor (TLR) stimulated whole blood. The CANTAB emotion recognition task (ERT) was administered to assess social cognition, and cortical connectivity was assessed based on resting DMN connectivity.

RESULTS

Higher IL-6 levels, measured both in plasma and in toll-like receptor (TLR-2) stimulated blood, were significantly correlated with higher CTQ scores and lower cognitive and social cognitive function. Plasma IL-6 was further observed to partly mediate the association between higher CT scores and lower emotion recognition performance (CTQ total: β_indirect -0.0234, 95% CI: -0.0573 to -0.0074; CTQ physical neglect: β_indirect = -0.0316, 95% CI: -0.0741 to -0.0049). Finally, sequential mediation was observed between plasma IL-6 levels and DMN connectivity in mediating the effects of higher CTQ on lower social cognitive function (β_indirect = -0.0618, 95% CI: -0.1523 to -0.285).

CONCLUSION

This work suggests that previous associations between CT and social cognition may be partly mediated via an increased inflammatory response. IL-6's association with changes in DMN activity further suggest at least one cortical network via which CT related effects on cognition may be transmitted.

Microglial-expressed genetic risk variants, cognitive function and brain volume in patients with schizophrenia and healthy controls

Changes in immune function are associated with variance in cognitive functioning in schizophrenia. Given that microglia are the primary innate immune cells in the brain, we examined whether schizophrenia risk-associated microglial genes (measured via polygenic score analysis) explained variation in cognition in patients with schizophrenia and controls (n = 1,238) and tested whether grey matter mediated this association. We further sought to replicate these associations in an independent sample of UK Biobank participants (n = 134,827). We then compared the strength of these microglial associations to that of neuronal and astroglial (i.e., other brain-expressed genes) polygenic scores, and used MAGMA to test for enrichment of these gene-sets with schizophrenia risk. Increased microglial schizophrenia polygenic risk was associated with significantly lower performance across several measures of cognitive functioning in both samples; associations which were then found to be mediated via total grey matter volume in the UK Biobank. Unlike neuronal genes which did show evidence of enrichment, the microglial gene-set was not significantly enriched for schizophrenia, suggesting that the relevance of microglia may be for neurodevelopmental processes related more generally to cognition. Further, the microglial polygenic score was associated with performance on a range of cognitive measures in a manner comparable to the neuronal schizophrenia polygenic score, with fewer cognitive associations observed for the astroglial score. In conclusion, our study supports the growing evidence of the importance of immune processes to understanding cognition and brain structure in both patients and in the healthy population.

Effect of child abuse and neglect on schizophrenia and other psychotic disorders

Childhood experiences impact long-term physical and behavioral health outcomes including potential risk for schizophrenia and psychosis. Negative experiences, such as child abuse and neglect, have been specifically associated with risk for schizophrenia and psychosis. This review provides a brief overview of child abuse and neglect, including its position within the larger field of trauma and adversity and its long term consequences. The link to schizophrenia is then explored. Principles of treatment and outcomes for schizophrenia with antecedent child abuse and neglect are then reviewed. Finally, next steps and points of prevention are highlighted.

Childhood maltreatment and social functioning in psychotic disorders: a systematic review protocol

Background: Childhood maltreatment (CM) is thought to play a key role in the etiology and course of psychotic disorders (PD). In addition, CM is related to neurobiological and clinical characteristics that can lead to poor social functioning. However, the extent to which CM and social functioning are directly associated in individuals with PD, is unclear. Therefore, we aim to systematically review the literature to provide an estimate on the strength of the association between CM and different domains of social functioning in PD and to summarize potential moderators and mediators of this association.Methods and analysis: To identify relevant studies, we will systematically search the following databases: Pubmed (Medline), PsycInfo, Embase, Web of Science (Core Collection), and Pilots (trauma), manually search reference lists and contact experts in the field. Studies will be included if they investigate and report on the association between CM (exposure) and social functioning (outcome) in adults with PD. Two independent reviewers will screen titles, abstracts and full texts according to eligibility criteria, perform data extraction and assess study quality according to a modified version of the Newcastle-Ottawa Scale.Analysis: Effect estimates will be pooled in a meta-analysis. Heterogeneity and publication bias will be assessed and the effects of potential moderators (genetic factors, type of diagnosis, duration of illness, type of CM and age at the time of CM exposure) will be analyzed using meta-regressions. Candidate moderators and mediators (neurocognition, cognitive schemas, comorbidities, stress sensitivity, attachment) will be also examined qualitatively.Ethics and dissemination: Because this review will make use of already published data, ethical approval will not be sought. This work has the potential to inform upcoming investigations on the association between the exposure to CM in PD and social functioning. PROSPERO registration number CRD42020175244.