Year: 2021
Type: article
Study design: Observational Study
Abstract: Mirror overflow is a developmental phenomenon defined as unintentional movements that mimic the execution of intentional movements in homologous muscles on the opposite side of the body. In children with attention-deficit/hyperactivity disorder (ADHD), mirror overflow is commonly excessive, abnormally persistent, and correlated with ADHD symptom severity. As such, it represents a promising clinical biomarker for disinhibited behavior associated with ADHD. Yet, the neural underpinnings of mirror overflow in ADHD remain unclear. Our objective was to test whether intrinsic interhemispheric functional connectivity between homologous regions of the somatomotor network (SMN) is associated with mirror overflow in school age children with and without ADHD using resting state functional magnetic resonance imaging. To this end, we quantified mirror overflow in 119 children (8-12 years old, 62 ADHD) during a finger sequencing task using finger twitch transducers affixed to the index and ring fingers. Group ICA was used to identify right- and left-lateralized SMNs and subject-specific back reconstructed timecourses were correlated to obtain a measure of SMN interhemispheric connectivity. We found that children with ADHD showed increased mirror overflow (p < 0.001; d = 0.671) and interhemispheric SMN functional connectivity (p = 0.023; d = 0.521) as compared to typically developing children. In children with ADHD, but not the typically developing children, there was a significant relationship between interhemispheric SMN functional connectivity and mirror overflow (t = 2.116; p = 0.039). Our findings of stronger interhemispheric functional connectivity between homologous somatomotor regions in children with ADHD is consistent with previous transcranial magnetic stimulation and diffusion-tractography imaging studies suggesting that interhemispheric cortical inhibitory mechanisms may be compromised in children with ADHD. The observed brain-behavior correlation further suggests that abnormally strong interhemispheric SMN connectivity in children with ADHD may diminish their ability to suppress overflow movements.
Source: NeuroImage Clinical
Institutions: Kennedy Krieger Institute, Johns Hopkins University
Language: English
Subfield: Psychiatry and Mental health
Field: Medicine
Domain: Health Sciences
Open Access status: gold
Estimated APC paid: $3,150
Awards: Intellectual and Developmental Disabilities Research Centers 2020, G2418509517, G2576110154, G2687347927, Movement-Based Training for Children with ADHD: A Feasibility Study, G3569141954, G4135647284, G5058301179, Adolescent Changes in Brain and Behavior in Boys and Girls with ADHD, G5532792246, 2/2 - Anomalous Motor System Physiology in ADHD: Biomarker Validation and Modeling Domains of Function, G6642544596, G6815082887, Visual-Motor Development in Infants at High Risk for Autism, G7036053010, G722803402, Delay Discounting in Children with ADHD: Neuroimaging and Behavioral Correlates, G8515121117, G8554137963, G8732932044, G9000229776, Neurobehavioral Correlates of Frustration in Children with ADHD
OpenAlex ID: W3178650306