ENIGMA-anxiety working group : Rationale for and organization of large-scale neuroimaging studies of anxiety disorders

Altres ajuts: Anxiety Disorders Research Network European College of Neuropsychopharmacology; Claude Leon Postdoctoral Fellowship; Deutsche Forschungsgemeinschaft (DFG, German Research Foundation, 44541416-TRR58); EU7th Frame Work Marie Curie Actions International Staff Exchange Scheme grant 'European and South African Research Network in Anxiety Disorders' (EUSARNAD); Geestkracht programme of the Netherlands Organization for Health Research and Development (ZonMw, 10-000-1002); Intramural Research Training Award (IRTA) program within the National Institute of Mental Health under the Intramural Research Program (NIMH-IRP, MH002781); National Institute of Mental Health under the Intramural Research Program (NIMH-IRP, ZIA-MH-002782); SA Medical Research Council; U.S. National Institutes of Health grants (P01 AG026572, P01 AG055367, P41 EB015922, R01 AG060610, R56 AG058854, RF1 AG051710, U54 EB020403).Anxiety disorders are highly prevalent and disabling but seem particularly tractable to investigation with translational neuroscience methodologies. Neuroimaging has informed our understanding of the neurobiology of anxiety disorders, but research has been limited by small sample sizes and low statistical power, as well as heterogenous imaging methodology. The ENIGMA-Anxiety Working Group has brought together researchers from around the world, in a harmonized and coordinated effort to address these challenges and generate more robust and reproducible findings. This paper elaborates on the concepts and methods informing the work of the working group to date, and describes the initial approach of the four subgroups studying generalized anxiety disorder, panic disorder, social anxiety disorder, and specific phobia. At present, the ENIGMA-Anxiety database contains information about more than 100 unique samples, from 16 countries and 59 institutes. Future directions include examining additional imaging modalities, integrating imaging and genetic data, and collaborating with other ENIGMA working groups. The ENIGMA consortium creates synergy at the intersection of global mental health and clinical neuroscience, and the ENIGMA-Anxiety Working Group extends the promise of this approach to neuroimaging research on anxiety disorders

The impact of stress on the prefrontal cortex: a view of how socioeconomic status impacts executive function

By the time they reach kindergarten, children from low Socioeconomic (SES) backgrounds lag behind their high SES peers in a host of cognitive abilities including executive function. The mechanism of how SES impacts executive function is still unclear; however, recent research eludes to the effects of stress regulation of the Hypothalamus-Pituitary-Adrenal (HPA) axis on cortical development as a promising explanation. Children raised in low SES backgrounds are exposed to a multitude of environmental stressors that can impact the child’s development of their stress response and regulation within the HPA axis. Alterations within the HPA axis, particularly cortisol levels, are shown to impact brain development especially the prefrontal cortex (PFC) which is a major region supporting executive function. Although the stress regulation mechanism seems valid, the influence of early life stress on the PFC and subsequent executive function outcomes have not been directly tested. The current study aimed to examine how earlier and concurrent responses to stress, as reflected in measures of cortisol reactivity, relate to neural and behavioral measures of executive function within the framework of how SES impacts executive function. This longitudinal study consisted of two waves of data collection, the first wave was collected when the children were 3-5 years old and the second wave when the children were 7-10 years old. Measures of executive functioning and cortisol stress response were collected during both waves, whereas structural and functional magnetic resonance imaging (MRI) of the brain were collected at the second wave. Although multiple analyses were conducted and numerous nonsignificant results were present, the significant results suggest variations in cortisol reactivity relate to executive function, overall brain volume, and regional differences in cortical thickness within the PFC including middle frontal cortex, inferior frontal cortex, insula, and anterior cingulate cortex. Within the bigger SES framework, SES was related to cortisol reactivity and executive function. SES differences were found in total grey matter and regional cortical thickness within the PFC including the insula and anterior cingulate cortex. The cortical thickness of the right inferior frontal cortex mediated the association between SES and executive function. The inferior frontal cortex and the anterior cingulate cortex were associated with both cortisol reactivity and SES suggesting these regions may contribute to the mechanism of how SES impacts executive function via stress regulation or dysregulation. Although future studies are necessary to replicate findings on a larger scale, the current study is an encouraging step towards understanding how differential stress responses along the socio-economic ladder impact brain and cognitive development

Understanding Cognitive Behavioral Therapy for Psychosis (CBTp) Through the Predictive Coding Framework

Psychological treatments for persecutory delusions, particularly cognitive behavioral therapy for psychosis (CBTp), are efficacious; but mechanistic theories explaining why they work rarely bridge to the level of cognitive neuroscience. Predictive coding, a general brain processing theory rooted in cognitive and computational neuroscience, has increasing experimental support in explaining the different symptoms of psychosis, including the formation and maintenance of delusions. Learning is central to both predictive coding and CBTp. Each emphasizes belief updating in response to new or surprising experiences. Despite their commonalities, treatment-related changes observed with CBTp have yet to be integrated into the predictive coding framework. Here, we outline how CBTp may mollify aberrant learning processes central to the predictive coding explanation of delusions. We first review hierarchical predictive coding as an account of belief updating rooted in prediction error signaling. We examine how this process is abnormal in psychotic disorders, specifically garnering delusion formation. We then posit that delusions persist via failure of extinction learning and inappropriate reconsolidation of delusional priors, promoted by excessive salience attribution to safe or neutral stimuli. We suggest that CBTp reduces reconsolidation of delusional priors and increases behaviors that strengthen non-delusional priors, ultimately promoting the updating of new, more adaptive beliefs. Persecutory delusions, which are associated with stronger prior beliefs about environmental volatility and show meaningful improvement with CBTp, are used as a specific example. Framing CBTp in this way proffers the exciting possibility of augmenting its impact by leveraging the insights of predictive coding

A practical guide for researchers and reviewers using the ABCD Study and other large longitudinal datasets.

As the largest longitudinal study of adolescent brain development and behavior to date, the Adolescent Brain Cognitive Development (ABCD) Study® has provided immense opportunities for researchers across disciplines since its first data release in 2018. The size and scope of the study also present a number of hurdles, which range from becoming familiar with the study design and data structure to employing rigorous and reproducible analyses. The current paper is intended as a guide for researchers and reviewers working with ABCD data, highlighting the features of the data (and the strengths and limitations therein) as well as relevant analytical and methodological considerations. Additionally, we explore justice, equity, diversity, and inclusion efforts as they pertain to the ABCD Study and other large-scale datasets. In doing so, we hope to increase both accessibility of the ABCD Study and transparency within the field of developmental cognitive neuroscience

A practical guide for researchers and reviewers using the ABCD Study and other large longitudinal datasets

As the largest longitudinal study of adolescent brain development and behavior to date, the Adolescent Brain Cognitive Development (ABCD) Study® has provided immense opportunities for researchers across disciplines since its first data release in 2018. The size and scope of the study also present a number of hurdles, which range from becoming familiar with the study design and data structure to employing rigorous and reproducible analyses. The current paper is intended as a guide for researchers and reviewers working with ABCD data, highlighting the features of the data (and the strengths and limitations therein) as well as relevant analytical and methodological considerations. Additionally, we explore justice, equity, diversity, and inclusion efforts as they pertain to the ABCD Study and other large-scale datasets. In doing so, we hope to increase both accessibility of the ABCD Study and transparency within the field of developmental cognitive neuroscience

Volume of subcortical brain regions in social anxiety disorder: mega-analytic results from 37 samples in the ENIGMA-Anxiety Working Group

There is limited convergence in neuroimaging investigations into volumes of subcortical brain regions in social anxiety disorder (SAD). The inconsistent findings may arise from variations in methodological approaches across studies, including sample selection based on age and clinical characteristics. The ENIGMA-Anxiety Working Group initiated a global mega-analysis to determine whether differences in subcortical volumes can be detected in adults and adolescents with SAD relative to healthy controls. Volumetric data from 37 international samples with 1115 SAD patients and 2775 controls were obtained from ENIGMA-standardized protocols for image segmentation and quality assurance. Linear mixed-effects analyses were adjusted for comparisons across seven subcortical regions in each hemisphere using family-wise error (FWE)-correction. Mixed-effects d effect sizes were calculated. In the full sample, SAD patients showed smaller bilateral putamen volume than controls (left: d = −0.077, pFWE = 0.037; right: d = −0.104, pFWE = 0.001), and a significant interaction between SAD and age was found for the left putamen (r = −0.034, pFWE = 0.045). Smaller bilateral putamen volumes (left: d = −0.141, pFWE < 0.001; right: d = −0.158, pFWE < 0.001) and larger bilateral pallidum volumes (left: d = 0.129, pFWE = 0.006; right: d = 0.099, pFWE = 0.046) were detected in adult SAD patients relative to controls, but no volumetric differences were apparent in adolescent SAD patients relative to controls. Comorbid anxiety disorders and age of SAD onset were additional determinants of SAD-related volumetric differences in subcortical regions. To conclude, subtle volumetric alterations in subcortical regions in SAD were detected. Heterogeneity in age and clinical characteristics may partly explain inconsistencies in previous findings. The association between alterations in subcortical volumes and SAD illness progression deserves further investigation, especially from adolescence into adulthood

ENIGMA-anxiety working group: Rationale for and organization of large-scale neuroimaging studies of anxiety disorders

Anxiety disorders are highly prevalent and disabling but seem particularly tractable to investigation with translational neuroscience methodologies. Neuroimaging has informed our understanding of the neurobiology of anxiety disorders, but research has been limited by small sample sizes and low statistical power, as well as heterogenous imaging methodology. The ENIGMA-Anxiety Working Group has brought together researchers from around the world, in a harmonized and coordinated effort to address these challenges and generate more robust and reproducible findings. This paper elaborates on the concepts and methods informing the work of the working group to date, and describes the initial approach of the four subgroups studying generalized anxiety disorder, panic disorder, social anxiety disorder, and specific phobia. At present, the ENIGMA-Anxiety database contains information about more than 100 unique samples, from 16 countries and 59 institutes. Future directions include examining additional imaging modalities, integrating imaging and genetic data, and collaborating with other ENIGMA working groups. The ENIGMA consortium creates synergy at the intersection of global mental health and clinical neuroscience, and the ENIGMA-Anxiety Working Group extends the promise of this approach to neuroimaging research on anxiety disorders