Dimensional thinking in psychiatry in the era of the Research Domain Criteria (RDoC)

Time will tell: Associations between unbalanced time perspectives and symptom severity in individuals with schizophrenia spectrum disorders

Patients with schizophrenia spectrum disorder (SSD) experience disrupted temporality on the immediate timescale. However, insufficient information is available for longer time frames, and the interaction of temporal perspectives with the clinical manifestations of SSD is unknown. We explored the association between unbalanced time perspectives and symptom severity. Thirty-seven Italian mental health services participating in the DiAPAson project recruited 620 patients with DSM-5 SSD (68 % males, mean age = 41.3 ± 9.5 years). Time perspective biases were measured using the Deviation from the Balanced Time Perspective-revisited (DBTP-r) indicator, based on Zimbardo Time Perspective Inventory (ZTPI) scores. Psychiatric symptoms were assessed using the Brief Psychiatric Rating Scale (BPRS) and Brief Negative Symptoms Scale (BNSS). Preliminary analyses examined the associations between ZTPI/DBTP-r and BPRS/BNSS total scores. In secondary analyses, we first tested the associations between the ZTPI/DBTP-r and BPRS/BNSS subscales and then compared ZTPI differences between patients with and without hallucinations, delusions, and conceptual disorganisation. Statistical significance was set at Holm-Bonferroni corrected p < 0.05. Low-to-moderate positive correlations were found between the DBTP-r and BPRS/BNSS total scores (r = 0.29/0.22). The strongest associations were between DBTP-r/ZTPI_Past-Negative and anxiety/depression (r = 0.34/0.36), followed by DBTP-r/ZTPI_Present-Fatalistic with thought disturbances (r = 0.22/0.20). DBTP-r was associated with BNSS anhedonia and avolition (r = 0.21/0.24). DBTP-r was higher in patients with hallucinations (ES = 0.391) and conceptual disorganisation (ES = 0.397) than in those without these symptoms. Unbalanced time perspective was positively associated with the severity of primary and secondary SSD features. These findings provide a rationale for empirical tests focused on balancing time perspectives in patients with SSD.

Compositional and Functional Alterations in Intestinal Microbiota in Patients with Psychosis or Schizophrenia: A Systematic Review and Meta-analysis

BACKGROUND AND HYPOTHESIS

Intestinal microbiota is intrinsically linked to human health. Evidence suggests that the composition and function of the microbiome differs in those with schizophrenia compared with controls. It is not clear how these alterations functionally impact people with schizophrenia. We performed a systematic review and meta-analysis to combine and evaluate data on compositional and functional alterations in microbiota in patients with psychosis or schizophrenia.

STUDY DESIGN

Original studies involving humans and animals were included. The electronic databases PsycINFO, EMBASE, Web of Science, PubMed/MEDLINE, and Cochrane were systematically searched and quantitative analysis performed.

STUDY RESULTS

Sixteen original studies met inclusion criteria (1376 participants: 748 cases and 628 controls). Ten were included in the meta-analysis. Although observed species and Chao 1 show a decrease in diversity in people with schizophrenia compared with controls (SMD = -0.14 and -0.66 respectively), that did not reach statistical significance. We did not find evidence for variations in richness or evenness of microbiota between patients and controls overall. Differences in beta diversity and consistent patterns in microbial taxa were noted across studies. We found increases in Bifidobacterium, Lactobacillus, and Megasphaera in schizophrenia groups. Variations in brain structure, metabolic pathways, and symptom severity may be associated with compositional alterations in the microbiome. The heterogeneous design of studies complicates a similar evaluation of functional readouts.

CONCLUSIONS

The microbiome may play a role in the etiology and symptomatology of schizophrenia. Understanding how the implications of alterations in microbial genes for symptomatic expression and clinical outcomes may contribute to the development of microbiome targeted interventions for psychosis.

Gut and oral microbiome modulate molecular and clinical markers of schizophrenia-related symptoms: A transdiagnostic, multilevel pilot study

Although increasing evidence links microbial dysbiosis with the risk for psychiatric symptoms through the microbiome-gut-brain axis (MGBA), the specific mechanisms remain poorly characterized. In a diagnostically heterogeneous group of treated psychiatric cases and nonpsychiatric controls, we characterized the gut and oral microbiome, plasma cytokines, and hippocampal inflammatory processes via proton magnetic resonance spectroscopic imaging (1H-MRSI). Using a transdiagnostic approach, these data were examined in association with schizophrenia-related symptoms measured by the Positive and Negative Syndrome Scale (PANSS). Psychiatric cases had significantly greater heterogeneity of gut alpha diversity and an enrichment of pathogenic taxa, like Veillonella and Prevotella, in the oral microbiome, which was an accurate classifier of phenotype. Cases exhibited significantly greater positive, negative, and general PANSS scores that uniquely correlated with bacterial taxa. Strong, positive correlations of bacterial taxa were also found with cytokines and hippocampal gliosis, dysmyelination, and excitatory neurotransmission. This pilot study supports the hypothesis that the MGBA influences psychiatric symptomatology in a transdiagnostic manner. The relative importance of the oral microbiome in peripheral and hippocampal inflammatory pathways was highlighted, suggesting opportunities for probiotics and oral health to diagnose and treat psychiatric conditions.

A transdiagnostic approach to negative symptoms: exploring factor structure and negative symptoms in bipolar disorders

Background

Negative symptoms are increasingly recognized as transdiagnostic phenomena, linked to reduced quality of life and functioning, and often caused or worsened by amendable external factors such as depression, social deprivation, side-effects of antipsychotics or substance use. The structure of negative symptoms fits into two dimensions: diminished expression and apathy. These may differ in association with external factors that influence their severity and may thus require different treatment approaches. The dimensions are comprehensively established in non-affective psychotic disorders but are understudied in bipolar disorders.

Methods

We conducted exploratory and confirmatory factor analyses in a sample of 584 individuals with bipolar disorder to assess the latent factor structure of negative symptoms as measured by the Positive and Negative Syndrome Scale (PANSS), and performed correlational analyses and multiple hierarchical regression analyses to investigate links between the two dimensions of negative symptoms and clinical and sociodemographic correlates.

Results

The latent factor structure of negative symptoms fits into two dimensions, i.e., diminished expression and apathy. A diagnosis of bipolar type I or a history of psychotic episodes predicted more severe levels of diminished expression. Depressive symptoms were associated with more severe negative symptoms across dimensions, yet 26.3% of euthymic individuals still displayed at least one mild or more severe negative symptom (PANSS score ≥ 3).

Discussion

The two-dimensional structure of negative symptoms seen in non-affective psychotic disorders reproduces in bipolar disorders indicating similarities in their phenomenology. Diminished expression was associated with a history of psychotic episodes and a diagnosis of BD-I, which may infer closer connections to psychosis liability. We found significantly less severe negative symptoms in euthymic than depressed participants. Nevertheless, more than a quarter of the euthymic individuals had at least one mild negative symptom, demonstrating some degree of persistence beyond depressed states.

Seeking the Psilocybiome: Psychedelics meet the microbiota-gut-brain axis

Moving towards a systems psychiatry paradigm embraces the inherent complex interactions across all levels from micro to macro and necessitates an integrated approach to treatment. Cortical 5-HT2A receptors are key primary targets for the effects of serotonergic psychedelics. However, the therapeutic mechanisms underlying psychedelic therapy are complex and traverse molecular, cellular, and network levels, under the influence of biofeedback signals from the periphery and the environment. At the interface between the individual and the environment, the gut microbiome, via the gut-brain axis, plays an important role in the unconscious parallel processing systems regulating host neurophysiology. While psychedelic and microbial signalling systems operate over different timescales, the microbiota-gut-brain (MGB) axis, as a convergence hub between multiple biofeedback systems may play a role in the preparatory phase, the acute administration phase, and the integration phase of psychedelic therapy. In keeping with an interconnected systems-based approach, this review will discuss the gut microbiome and mycobiome and pathways of the MGB axis, and then explore the potential interaction between psychedelic therapy and the MGB axis and how this might influence mechanism of action and treatment response. Finally, we will discuss the possible implications for a precision medicine-based psychedelic therapy paradigm.

Evaluation of delay discounting as a transdiagnostic research domain criteria indicator in 1388 general community adults

BACKGROUND

The Research Domain Criteria (RDoC) approach proposes a novel psychiatric nosology using transdiagnostic dimensional mechanistic constructs. One candidate RDoC indicator is delay discounting (DD), a behavioral economic measure of impulsivity, based predominantly on studies examining DD and individual conditions. The current study sought to evaluate the transdiagnostic significance of DD in relation to several psychiatric conditions concurrently.

METHODS

Participants were 1388 community adults (18-65) who completed an in-person assessment, including measures of DD, substance use, depression, anxiety, posttraumatic stress disorder, and attention-deficit hyperactivity disorder (ADHD). Relations between DD and psychopathology were examined with three strategies: first, examining differences by individual condition using clinical cut-offs; second, examining DD in relation to latent psychopathology variables via principal components analysis (PCA); and third, examining DD and all psychopathology simultaneously via structural equation modeling (SEM).

RESULTS

Individual analyses revealed elevations in DD were present in participants screening positive for multiple substance use disorders (tobacco, cannabis, and drug use disorder), ADHD, major depressive disorder (MDD), and an anxiety disorder (ps < 0.05-0.001). The PCA produced two latent components (substance involvement v. the other mental health indicators) and DD was significantly associated with both (ps < 0.001). In the SEM, unique significant positive associations were observed between the DD latent variable and tobacco, cannabis, and MDD (ps < 0.05-0.001).

CONCLUSIONS

These results provide some support for DD as a transdiagnostic indicator, but also suggest that studies of individual syndromes may include confounding via comorbidities. Further systematic investigation of DD as an RDoC indicator is warranted.

The psychedelic renaissance: the next trip for psychiatry?

The psychedelic research renaissance is gaining traction. Preliminary clinical studies of the hallucinogenic fungi, psilocybin, with psychological support, have indicated improvements in mood, anxiety and quality of life. A seminal, open-label study demonstrated marked reductions in depression symptoms in participants with treatment-resistant depression (TRD). The associated neurobiological processes involve alterations in brain connectivity, together with altered amygdala and default mode network activity. At the cellular level, psychedelics promote synaptogenesis and neural plasticity. Prompted by the promising preliminary studies, a randomized, double-blind trial has recently been launched across Europe and North America to investigate the efficacy of psilocybin in TRD. One of these centres is based in Ireland - CHO Area 7 and Tallaght University Hospital. The outcome of this trial will determine whether psilocybin with psychological support will successfully translate into the psychiatric clinic for the benefit of patients.

Stressor-Specific Microbiota Intervention

To date, mental disorders are diagnosed and treated by the subjective judgment of psychiatrists based on diagnostic criteria and treatment guidelines, respectively. Mental disorders are heterogeneous illnesses with a substantial treatment-refractory rate. Thus, there is a great need for novel treatment approaches. This article proposes a treatment approach centered on the concept of the gut–brain axis. There is mounting evidence indicating an association between stressors, microbiota, microglia, and mental disorders. Stressors might facilitate dysbiosis, inflammation, and the occurrence of mental disorders. This novel treatment approach is based on the idea that stressor types instead of the heterogeneous psychiatric diagnosis might be closer to the neurobiological underpinnings of mental disorders. First of all, patients with treatment-resistant mental disorders will be asked to describe their major stressors. Then, clinicians will calculate the total threat score and the total deprivation score. Subsequently, treatment tailored to the major stressor type will be administered to restore a healthy gut microbiome. Presumably, treatment will be aimed at increasing microbiota diversity in those who mainly have deprivation stressors and boosting Actinobacteria in those who have mainly threat stressors. Large-scale clinical trials are warranted to test this hypothetical approach.

Psychedelic Therapy's Transdiagnostic Effects: A Research Domain Criteria (RDoC) Perspective

Accumulating clinical evidence shows that psychedelic therapy, by synergistically combining psychopharmacology and psychological support, offers a promising transdiagnostic treatment strategy for a range of disorders with restricted and/or maladaptive habitual patterns of emotion, cognition and behavior, notably, depression (MDD), treatment resistant depression (TRD) and addiction disorders, but perhaps also anxiety disorders, obsessive-compulsive disorder (OCD), Post-Traumatic Stress Disorder (PTSD) and eating disorders. Despite the emergent transdiagnostic evidence, the specific clinical dimensions that psychedelics are efficacious for, and associated underlying neurobiological pathways, remain to be well-characterized. To this end, this review focuses on pre-clinical and clinical evidence of the acute and sustained therapeutic potential of psychedelic therapy in the context of a transdiagnostic dimensional systems framework. Focusing on the Research Domain Criteria (RDoC) as a template, we will describe the multimodal mechanisms underlying the transdiagnostic therapeutic effects of psychedelic therapy, traversing molecular, cellular and network levels. These levels will be mapped to the RDoC constructs of negative and positive valence systems, arousal regulation, social processing, cognitive and sensorimotor systems. In summarizing this literature and framing it transdiagnostically, we hope we can assist the field in moving toward a mechanistic understanding of how psychedelics work for patients and eventually toward a precise-personalized psychedelic therapy paradigm.

Perturbations in Gut Microbiota Composition in Psychiatric Disorders: A Review and Meta-analysis

Importance

Evidence of gut microbiota perturbations has accumulated for multiple psychiatric disorders, with microbiota signatures proposed as potential biomarkers. However, no attempts have been made to evaluate the specificity of these across the range of psychiatric conditions.

Objective

To conduct an umbrella and updated meta-analysis of gut microbiota alterations in general adult psychiatric populations and perform a within- and between-diagnostic comparison.

Data Sources

Cochrane Library, PubMed, PsycINFO, and Embase were searched up to February 2, 2021, for systematic reviews, meta-analyses, and original evidence.

Study Selection

A total of 59 case-control studies evaluating diversity or abundance of gut microbes in adult populations with major depressive disorder, bipolar disorder, psychosis and schizophrenia, anorexia nervosa, anxiety, obsessive compulsive disorder, posttraumatic stress disorder, or attention-deficit/hyperactivity disorder were included.

Data Extraction and Synthesis

Between-group comparisons of relative abundance of gut microbes and beta diversity indices were extracted and summarized qualitatively. Random-effects meta-analyses on standardized mean difference (SMD) were performed for alpha diversity indices.

Main Outcomes and Measures

Alpha and beta diversity and relative abundance of gut microbes.

Results

A total of 34 studies provided data and were included in alpha diversity meta-analyses (n = 1519 patients, n = 1429 control participants). Significant decrease in microbial richness in patients compared with control participants were found (observed species SMD = -0.26; 95% CI, -0.47 to -0.06; Chao1 SMD = -0.5; 95% CI, -0.79 to -0.21); however, this was consistently decreased only in bipolar disorder when individual diagnoses were examined. There was a small decrease in phylogenetic diversity (SMD = -0.24; 95% CI, -0.47 to -0.001) and no significant differences in Shannon and Simpson indices. Differences in beta diversity were consistently observed only for major depressive disorder and psychosis and schizophrenia. Regarding relative abundance, little evidence of disorder specificity was found. Instead, a transdiagnostic pattern of microbiota signatures was found. Depleted levels of Faecalibacterium and Coprococcus and enriched levels of Eggerthella were consistently shared between major depressive disorder, bipolar disorder, psychosis and schizophrenia, and anxiety, suggesting these disorders are characterized by a reduction of anti-inflammatory butyrate-producing bacteria, while pro-inflammatory genera are enriched. The confounding associations of region and medication were also evaluated.

Conclusions and Relevance

This systematic review and meta-analysis found that gut microbiota perturbations were associated with a transdiagnostic pattern with a depletion of certain anti-inflammatory butyrate-producing bacteria and an enrichment of pro-inflammatory bacteria in patients with depression, bipolar disorder, schizophrenia, and anxiety.

Mindfulness Meditation: Impact on Attentional Control and Emotion Dysregulation

OBJECTIVE

Theoretical models of mindfulness meditation conceptualize the cultivation of focused attention and regulation of emotional states, with the attitudinal foundations that promote nonjudgment and acceptance, to facilitate cognitive and affective processing resulting in improved brain health. Within the scientific study of mindfulness meditation, outcomes assessing behavioral and neural correlates of attentional control and emotion regulation have been examined for their malleability as a function of engagement in mindfulness practices. This review synthesizes the results of our pilot trials examining the preliminary effects of mindfulness meditation on metrics of cognitive, affective, and brain health in older adults and in individuals with multiple sclerosis.

CONCLUSIONS

There is promising support for mindfulness meditation to enhance attentional control, reduce mind-wandering, and reduce emotion dysregulation. However, well-powered efficacy trials, with an objective assessment of mindfulness practice data are needed to further provide causal and comprehensive evidence supporting the efficacy of mindfulness meditation for brain health. Inclusion of independently derived and validated brain-based signatures of cognitive and affective functioning can additionally enable a parsimonious understanding of how mindfulness meditation can causally impact metrics of functional and structural integrity of the human brain.

Psychiatric Neural Networks and Precision Therapeutics by Machine Learning

Learning and environmental adaptation increase the likelihood of survival and improve the quality of life. However, it is often difficult to judge optimal behaviors in real life due to highly complex social dynamics and environment. Consequentially, many different brain regions and neuronal circuits are involved in decision-making. Many neurobiological studies on decision-making show that behaviors are chosen through coordination among multiple neural network systems, each implementing a distinct set of computational algorithms. Although these processes are commonly abnormal in neurological and psychiatric disorders, the underlying causes remain incompletely elucidated. Machine learning approaches with multidimensional data sets have the potential to not only pathologically redefine mental illnesses but also better improve therapeutic outcomes than DSM/ICD diagnoses. Furthermore, measurable endophenotypes could allow for early disease detection, prognosis, and optimal treatment regime for individuals. In this review, decision-making in real life and psychiatric disorders and the applications of machine learning in brain imaging studies on psychiatric disorders are summarized, and considerations for the future clinical translation are outlined. This review also aims to introduce clinicians, scientists, and engineers to the opportunities and challenges in bringing artificial intelligence into psychiatric practice.

Single and Cross-Disorder Detection for Autism and Schizophrenia

Detection of mental disorders from textual input is an emerging field for applied machine and deep learning methods. Here, we explore the limits of automated detection of autism spectrum disorder (ASD) and schizophrenia (SCZ). We compared the performance of: (1) dedicated diagnostic tools that involve collecting textual data, (2) automated methods applied to the data gathered by these tools, and (3) psychiatrists. Our article tests the effectiveness of several baseline approaches, such as bag of words and dictionary-based vectors, followed by a machine learning model. We employed two more refined Sentic text representations using affective features and concept-level analysis on texts. Further, we applied selected state-of-the-art deep learning methods for text representation and inference, as well as experimented with transfer and zero-shot learning. Finally, we also explored few-shot methods dedicated to low data size scenarios, which is a typical problem for the clinical setting. The best breed of automated methods outperformed human raters (psychiatrists). Cross-dataset approaches turned out to be useful (only from SCZ to ASD) despite different data types. The few-shot learning methods revealed promising results on the SCZ dataset. However, more effort is needed to explore the approaches to efficiently training models, given the very limited amounts of labeled clinical data. Psychiatry is one of the few medical fields in which the diagnosis of most disorders is based on the subjective assessment of a psychiatrist. Therefore, the introduction of objective tools supporting diagnostics seems to be pivotal. This paper is a step in this direction.

Psychedelic science in post-COVID-19 psychiatry

The medium- to long-term consequences of COVID-19 are not yet known, though an increase in mental health problems are predicted. Multidisciplinary strategies across socio-economic and psychological levels may be needed to mitigate the mental health burden of COVID-19. Preliminary evidence from the rapidly progressing field of psychedelic science shows that psilocybin therapy offers a promising transdiagnostic treatment strategy for a range of disorders with restricted and maladaptive habitual patterns of cognition and behaviour, notably depression, addiction and obsessive compulsive disorder. The COMPASS Pathways (COMPASS) phase 2b double-blind trial of psilocybin therapy in antidepressant-free, treatment-resistant depression (TRD) is underway to determine the safety, efficacy and optimal dose of psilocybin. Results from the Imperial College London Psilodep-RCT comparing the efficacy and mechanisms of action of psilocybin therapy to the selective serotonin reuptake inhibitor (SSRI) escitalopram will soon be published. However, the efficacy and safety of psilocybin therapy in conjunction with SSRIs in TRD is not yet known. An additional COMPASS study, with a centre in Dublin, will begin to address this question, with potential implications for the future delivery of psilocybin therapy. While at a relatively early stage of clinical development, and notwithstanding the immense challenges of COVID-19, psilocybin therapy has the potential to play an important therapeutic role for various psychiatric disorders in post-COVID-19 clinical psychiatry.

A Systematic Review of Imaging Studies in the Combined and Inattentive Subtypes of Attention Deficit Hyperactivity Disorder

Objective: Insights to underlying neural mechanisms in attention deficit hyperactivity disorder (ADHD) have emerged from neuroimaging research; however, the neural mechanisms that distinguish ADHD subtypes remain inconclusive.

Method: We reviewed 19 studies integrating magnetic resonance imaging [MRI; structural (sMRI), diffusion, functional MRI (fMRI)] findings into a framework exploring pathophysiological mechanisms underlying the combined (ADHD-C) and predominantly inattentive (ADHD-I) ADHD subtypes.

Results: Despite equivocal structural MRI results, findings from fMRI and DTI imaging modalities consistently implicate disrupted connectivity in regions and tracts involving frontal striatal thalamic in ADHD-C and frontoparietal neural networks in ADHD-I. Alterations of the default mode, cerebellum, and motor networks in ADHD-C and cingulo-frontoparietal attention and visual networks in ADHD-I highlight network organization differences between subtypes.

Conclusion: Growing evidence from neuroimaging studies highlight neurobiological differences between ADHD clinical subtypes, particularly from a network perspective. Understanding brain network organization and connectivity may help us to better conceptualize the ADHD types and their symptom variability.

Mentalexo approach for diagnosis of psychiatric disorders

INTRODUCTION

Psychiatric disorders cause a high burden of disease and disability for the society. Liquid biopsies provide potent opportunities for screening programs, diagnosis, prognostic stratification and treatment monitorization. Previously, the liquid biopsy studies were mainly focused on the several malignancies without proper screen methods, but this approach has also a strong potential for decreasing disease burden in CNS pathologies. The main restriction for the diagnosis of CNS diseases is the lack of the methods to receive biochemical/functional information form a tightly enveloped compartment.

THE HYPOTHESIS/THEORY

In this proposal, we aim to develop a fast and cheap diagnostic platform based on the detection of exosomes originating from the central nervous system (CNS) cells. We intended to develop a sensor device with minimum maintenance costs, which is highly specific and sensitive for psychiatric diseases.

EVALUATION OF THE HYPOTHESIS/IDEA

In order to give background information for our proposal; we began with reviewing the concept of liquid biopsies and adaptation of this concept for psychiatric disorders. Then we discussed the conventional and novel methods for the detection of extracellular vesicles (EV). Furthermore, we discussed the detection of exosomes originating from central nervous system and methods analyzing the content of the EVs. Additionally, we reviewed the imaging techniques for detection and visualization of EVs.

EMPIRICAL DATA

We used in silico research tools (MetaCore™ version 6.37, Clarivate Analytics, and ExoCarta database) to detect appropriate disease specific exosomal markers. We proposed our design for the detection of EVs based on the immune-capture of EVs and detection of surface antigens via the antibody conjugated fluorophores. We also proposed a design to increase the channels for detection of exosomal antigens by using bioinformatics methods, including pathway networks, RDOC matrices and exosome databases which we called "Mentalexo" approach. We applied this approach on depression and addiction disorders in order to find appropriate exosomal markers.

CONSEQUENCES OF THE HYPOTHESIS AND DISCUSSION

We believe that our proposal may contribute to the conception of new diagnostic devices focusing on the detection of exosomes in psychiatric conditions.

Psychometric Properties of the Emotion Dysregulation Inventory in a Nationally Representative Sample of Youth

Objective: The Emotion Dysregulation Inventory (EDI) is an informant questionnaire developed based on the Patient-Reported Outcomes Measurement Information System (PROMIS®) Scientific Standards and refined through factor analyses and item response theory (IRT) analyses. Although it was developed to improve measurement of emotion dysregulation in youth with autism spectrum disorder, emotion dysregulation has transdiagnostic significance. Therefore, the aim of this study was to evaluate the EDI's psychometric properties and to establish IRT-based scores for a general population of youth.Methods: Data were collected from a sample of 1000 caregivers of 6- to 17-year-old youth matched to the US census on age, gender, race/ethnicity, years of education, and region. Confirmatory factor analyses and IRT analyses using the two-parameter graded response model were performed to evaluate the EDI's structure and psychometric properties.Results: Analyses supported the original two-factor structure of the EDI, reflecting factors for Reactivity and Dysphoria. Simulations of computerized adaptive testing supported use of the same items for a Reactivity short form as those that emerged as most informative in the original autism psychometric analyses. IRT co-calibration with commonly used measures of emotion regulation and irritability in child clinical or community samples indicated the EDI scales provide more information across a wider range of emotion dysregulation. Validity was supported by moderate correlations with measures of related constructs and expected known-group differences.Conclusions: The EDI is an efficient and precise measure of emotion dysregulation for use in general community and clinical samples as well as samples of youth with ASD.

A Transdisciplinary Integrative Approach for Precision Psychiatry

Theoretical psychiatry considers theoretical problems in psychiatry as well as the quality and effectiveness of mental health care. This chapter addresses the idea of predictive, preventive, precision, personalized, and participatory medicine in psychiatry from a theoretical transdisciplinary integrative perspective and systems networking. The aim of the chapter is to bring together some current ideas and concepts such as computational neuroscience, network theory, multi-omics profile, precision medicine, and person-centered psychiatry as a coherent system of theory and practice.

Psychosocial dimensions of hand transplantation: lessons learned from solid organ transplantation

PURPOSE OF REVIEW

The present review examines psychosocial factors emerging as predictive of clinical outcomes among solid organ transplant (SOT) recipients, with possible extensions to vascular composite allograft (VCA) and hand transplantation, in particular. The Chauvet Workgroup report and International Society of Heart and Lung Transplantation consensus guidelines are used to delineate areas of commonality between SOT and VCA, as well as unique features contributing to post-VCA psychosocial risk.

RECENT FINDINGS

Increasing evidence suggests that depression, cognitive function, and other posttransplant psychosocial factors consistently associate with clinical risk in SOT. However, the mechanisms precipitating these psychosocial risk factors are likely diverse in their cause, with large individual differences across SOT and VCA. Transdiagnostic dimensions may serve as mechanistic factors, increasing the risk of adverse clinical outcomes and suggesting potential treatment strategies for risk mitigation. Psychosocial dimensions including psychological flexibility, self-efficacy, and posttraumatic growth are discussed as potential contributory factors.

SUMMARY

Psychosocial factors hold importance in predicting posttransplant clinical outcomes. Emerging transdiagnostic factors may provide insight into mechanisms and potential treatments.

Mood and Microbes: Gut to Brain Communication in Depression

The gut microbiota, acting via the gut-brain axis, modulates key neurobiological systems that are dysregulated in stress-related disorders. Preclinical studies show that the gut microbiota exerts an influence over neuroimmune and neuroendocrine signaling pathways, in addition to epigenetic modification, neurogenesis, and neurotransmission. In humans, preliminary evidence suggests that the gut microbiota profile is altered in depression. The full impact of microbiota-based treatments, at different neurodevelopmental time points, has yet to be fully explored. The integration of the gut microbiota, as a mediator, in the complex trajectory of depression, may enhance the possibility of personalized precision psychiatry.

Obsessive-Compulsive Symptoms in Schizophrenia: an Up-To-Date Review of Literature

PURPOSE OF REVIEW

This review will aim to summarize the current body of epidemiological, clinical and therapeutic knowledge concerning specific co-occurrence of obsessive-compulsive symptoms (OCSs) and schizophrenia spectrum disorder.

RECENT FINDINGS

Almost 30% of the patients with schizophrenia display OCS, and three main contexts of emergence are identified: prodromal symptoms of schizophrenia, co-occurrence of OCS and schizophrenia and antipsychotics-induced OCS. Recent clinical studies show that patients with SZ and OCS have more severe psychotic and depressive symptoms, higher suicidality and lower social functioning. A recent cognitive investigation found that OCS and delusions share specific metacognitive profiles, particularly through a heightened need to control thoughts. Finally, a recent cross-sectional study of clozapine-induced OCS found a dose-response relationship between clozapine and OCS. OCS appeared reliably as linked to poorer outcomes among patients with schizophrenia. However, the specific clinical value of OCS among other prodromal symptoms of schizophrenia remains unknown.

Level of Insight in Patients With Obsessive-Compulsive Disorder: An Exploratory Comparative Study Between Patients With "Good Insight" and "Poor Insight"

Introduction: Insight may be defined as the ability to perceive and evaluate external reality and to separate it from its subjective aspects. It also refers to the ability to self-assess difficulties and personal qualities. Insight may be a predictor of success in the treatment of obsessive-compulsive disorder (OCD), so that individuals with poor insight tend to become refractory to treatment. The objective of this study is to investigate factors associated with poor insight in individuals with OCD. Methods: This cross-sectional exploratory study used the Brown Belief Assessment Scale as a parameter for the creation of the comparison groups: individuals who obtained null scores (zero) composed the group with preserved or good insight (n = 148), and those with scores above the 75% percentile composed the group with poor insight (n = 124); those with intermediate scores were excluded. Sociodemographic characteristics and clinical and psychopathological aspects, intrinsic and extrinsic to the typical symptoms of OCD, were compared in a univariate analysis. A logistic regression was used to determine which factors associated with critical judgment remained significant. Results: Individuals in the poor insight group differed from those with good insight in regard to: more prevalent use of neuroleptics (p = 0.05); higher untreated time interval (p < 0.001); higher total Yale-Brown obsessive-compulsive scale score and the obsessions and compulsions factors (all factors with p < 0.001); higher dimensional Yale-Brown obsessive-compulsive scale total and dimensional scores (p from 0.04 to 0.001); higher prevalence of contamination/cleaning (p = 0.006) and hoarding (p < 0.001) symptoms dimensions; more prevalent sensory phenomena (p = 0.023); higher levels of depression (p = 0.007); and more prevalent comorbidity with bipolar affective disorder (p = 0.05) and post-traumatic stress disorder (PTSD) (p = 0.04). After analyzing the logistic regression, we conclude that the most important factors associated with poor insight are: the presence of any sensory phenomena (OR: 2.24), use of neuroleptics (OR: 1.66), and hoarding symptoms (OR: 1.15). Conclusion: The variability of insight in patients with OCD seems to be an important psychopathological characteristic in the differentiation of possible subtypes of OCD, since the poor insight is associated with sensory phenomena and greater use of neuroleptics, which makes it possible to conjecture the role of dopaminergic neurocircuits in the neurobiology of this disorder. In addition, there is also an association with the symptoms of hoarding content, admittedly one of the symptomatic contents with less response to conventional OCD treatments. Studies based on neurobiological aspects such as neuroimaging and neuropsychology may help to elucidate more consistently the role of insight in patients with OCD and the repercussions concerning available treatments.

Cross Talk: The Microbiota and Neurodevelopmental Disorders

Humans evolved within a microbial ecosystem resulting in an interlinked physiology. The gut microbiota can signal to the brain via the immune system, the vagus nerve or other host-microbe interactions facilitated by gut hormones, regulation of tryptophan metabolism and microbial metabolites such as short chain fatty acids (SCFA), to influence brain development, function and behavior. Emerging evidence suggests that the gut microbiota may play a role in shaping cognitive networks encompassing emotional and social domains in neurodevelopmental disorders. Drawing upon pre-clinical and clinical evidence, we review the potential role of the gut microbiota in the origins and development of social and emotional domains related to Autism spectrum disorders (ASD) and schizophrenia. Small preliminary clinical studies have demonstrated gut microbiota alterations in both ASD and schizophrenia compared to healthy controls. However, we await the further development of mechanistic insights, together with large scale longitudinal clinical trials, that encompass a systems level dimensional approach, to investigate whether promising pre-clinical and initial clinical findings lead to clinical relevance.