Investigating brain dynamics and their association with cognitive control in opioid use disorder using naturalistic and drug cue paradigms.

Objectives: Opioid use disorder (OUD) impacts millions of people worldwide. The prevalence and debilitating effects of OUD present a pressing need to understand its neural mechanisms to provide more targeted interventions. Prior studies have linked altered functioning in large-scale brain networks with clinical symptoms and outcomes in OUD.

Altered extracellular matrix dynamics is associated with insulin resistance in adolescent children with obesity.

Objective: The objective of this study was to examine the hypothesis that abdominal and gluteal adipocyte turnover, lipid dynamics, and fibrogenesis are dysregulated among insulin-resistant (IR) compared with insulin-sensitive (IS) adolescents with obesity.

Methods: Seven IS and seven IR adolescents with obesity participated in a 3-h oral glucose tolerance test and a multi-section magnetic resonance imaging scan of the abdominal region to examine body fat distribution patterns and liver fat content. An 8-week 70% deuterated water ( H O) labeling protocol examined adipocyte turnover, lipid dynamics, and fibrogenesis in vivo from biopsied abdominal and gluteal fat.

Rising NAFLD and metabolic severity during the Sars-CoV-2 pandemic among children with obesity in the United States.

Objective: Nonalcoholic fatty liver disease (NAFLD), the most common liver disease among youth with obesity, precedes more severe metabolic and liver diseases. However, the impact of the Sars-CoV-2 global pandemic on the prevalence and severity of NAFLD and the associated metabolic phenotype among youth with obesity is unknown.

Methods: Participants were recruited from the Yale Pediatric Obesity Clinic during the Sars-CoV-2 global pandemic (August 2020 to May 2022) and were compared with a frequency-matched control group of youth with obesity studied before the Sars-CoV-2 global pandemic (January 2017 to November 2019).

Brain-phenotype models fail for individuals who defy sample stereotypes.

Individual differences in brain functional organization track a range of traits, symptoms and behaviours. So far, work modelling linear brain-phenotype relationships has assumed that a single such relationship generalizes across all individuals, but models do not work equally well in all participants. A better understanding of in whom models fail and why is crucial to revealing robust, useful and unbiased brain-phenotype relationships.

Arousal impacts distributed hubs modulating the integration of brain functional connectivity.

Even when subjects are at rest, it is thought that brain activity is organized into distinct brain states during which reproducible patterns are observable. Yet, it is unclear how to define or distinguish different brain states. A potential source of brain state variation is arousal, which may play a role in modulating functional interactions between brain regions.

Dynamic-flip-angle ECG-gating with nuisance signal regression improves resting-state BOLD functional connectivity mapping by reducing cardiogenic noise.

Purpose: To investigate an ECG-gated dynamic-flip-angle BOLD sequence with improved robustness against cardiogenic noise in resting-state fMRI.

Methods: ECG-gating minimizes the cardiogenic noise but introduces T -dependent signal variation, which is minimized by combination of a dynamic-flip-angle technique and retrospective nuisance signal regression (NSR) using signals of white matter, CSF, and global average. The technique was studied with simulations in a wide range of T and B fields and phantom imaging with pre-programmed TR variations.

Data-Driven Analysis of Functional Connectivity Reveals a Potential Auditory Verbal Hallucination Network.

Schizophrenia is a severe global health problem, with over half of such patients experiencing auditory verbal hallucinations (AVHs). A better understanding of the neural correlates differentiating patients experiencing AVHs from patients not experiencing AVHs and healthy controls may identify targets that lead to better treatment strategies for AVHs. Employing 2 data-driven, voxel-based measure of functional connectivity, we studied 46 patients with schizophrenia or schizoaffective disorder (28 experiencing AVHs and 18 not experiencing AVHs).

Influences on the Test-Retest Reliability of Functional Connectivity MRI and its Relationship with Behavioral Utility.

Best practices are currently being developed for the acquisition and processing of resting-state magnetic resonance imaging data used to estimate brain functional organization-or "functional connectivity." Standards have been proposed based on test-retest reliability, but open questions remain. These include how amount of data per subject influences whole-brain reliability, the influence of increasing runs versus sessions, the spatial distribution of reliability, the reliability of multivariate methods, and, crucially, how reliability maps onto prediction of behavior.

Fluctuations in Global Brain Activity Are Associated With Changes in Whole-Brain Connectivity of Functional Networks.

Objective: The aim of this study was to explore the relationship between global brain activity, changes in whole-brain connectivity, and changes in brain states across subjects using resting-state functional magnetic resonance imaging.

Methods: We extended current methods that use a sparse set of coactivation patterns to extract critical time points in global brain activity. Critical activity time points were defined as points where the global signal is greater than one standard deviation above or below the average global signal.

Sex differences in normal age trajectories of functional brain networks.

Resting-state functional magnetic resonance image (rs-fMRI) is increasingly used to study functional brain networks. Nevertheless, variability in these networks due to factors such as sex and aging is not fully understood. This study explored sex differences in normal age trajectories of resting-state networks (RSNs) using a novel voxel-wise measure of functional connectivity, the intrinsic connectivity distribution (ICD).

Altered functional connectivity in seizure onset zones revealed by fMRI intrinsic connectivity.

Objective: The purpose of this study was to investigate functional connectivity (FC) changes in epileptogenic networks in intractable partial epilepsy obtained from resting-state fMRI by using intrinsic connectivity contrast (ICC), a voxel-based network measure of degree that reflects the number of connections to each voxel.

Methods: We measured differences between intrahemispheric- and interhemispheric-ICC (ICCintra-inter) that could reveal localized connectivity abnormalities in epileptogenic zones while more global network changes would be eliminated when subtracting these values. The ICCintra-inter map was compared with the seizure onset zone (SOZ) based on intracranial EEG (icEEG) recordings in 29 patients with at least 1 year of postsurgical follow-up.

Modulating intrinsic connectivity: adjacent subregions within supplementary motor cortex, dorsolateral prefrontal cortex, and parietal cortex connect to separate functional networks during task and also connect during rest.

Supplementary motor area (SMA), the inferior frontal junction (IFJ), superior frontal junction (SFJ) and parietal cortex are active in many cognitive tasks. In a previous study, we found that subregions of each of these major areas were differentially active in component processes of executive function during working memory tasks. In the present study, each of these subregions was used as a seed in a whole brain functional connectivity analysis of working memory and resting state data.

Intrinsic brain connectivity related to age in young and middle aged adults.

Age-related variations in resting state connectivity of the human brain were examined from young adulthood through middle age. A voxel-based network measure, degree, was used to assess age-related differences in tissue connectivity throughout the brain. Increases in connectivity with age were found in paralimbic cortical and subcortical regions.

Social network theory applied to resting-state fMRI connectivity data in the identification of epilepsy networks with iterative feature selection.

Epilepsy is a brain disorder usually associated with abnormal cortical and/or subcortical functional networks. Exploration of the abnormal network properties and localization of the brain regions involved in human epilepsy networks are critical for both the understanding of the epilepsy networks and planning therapeutic strategies. Currently, most localization of seizure networks come from ictal EEG observations.

Brain areas coactivating with motor cortex during chronic motor tics and intentional movements.

Background: Chronic tic disorders are characterized by motor tics that are often preceded by premonitory urges to tic. Functional neuroimaging studies have documented brain activity patterns prior to and during tics, but these studies have not examined whether the activation patterns differ from those seen in normal control subjects performing similar acts.

Methods: A novel method was used to compare brain patterns during tics and intentional movements.

Acupuncture-induced blood oxygenation level-dependent signals in awake and anesthetized volunteers: a pilot study.

Background: There are conflicting data regarding clinical efficacy of acupuncture applied while patients are under general anesthesia. We hypothesize that these conflicting data are a result of the inhibitory effect of anesthesia on acupuncture-induced central nervous system activity that can be demonstrated using magnetic resonance imaging.

Methods: Using a crossover study design, volunteers received standardized Stomach 36 manual acupuncture in two experimental conditions: while undergoing a propofol-based general anesthetic, and while awake.

Connectivity-behavior analysis reveals that functional connectivity between left BA39 and Broca's area varies with reading ability.

Correlations between temporal fluctuations in MRI signals may reveal functional connectivity between brain regions within individual subjects. Such correlations would be especially useful indices of functional connectivity if they covary with behavioral performance or other subject variables. This study investigated whether such a relationship could be demonstrated in the context of the reading circuit in the brain.