Subtle motor signs in children with ADHD and their white matter correlates

• Published in: Human brain mapping Vol. 45; no. 14; pp. e70002 - n/a
• Main Authors: Hyde, C., Fuelscher, I., Rosch, K. S., Seymour, K. E., Crocetti, D., Silk, T., Singh, M., Mostofsky, S. H.
• Format: Journal Article
• Language: English
• Published: Hoboken, USA John Wiley & Sons, Inc 01.10.2024
• Subjects: Abnormalities; ADHD; Attention Deficit Disorder with Hyperactivity - diagnostic imaging; Attention Deficit Disorder with Hyperactivity - pathology; Attention Deficit Disorder with Hyperactivity - physiopathology; Attention deficit hyperactivity disorder; Brain - diagnostic imaging; Brain - pathology; Brain - physiopathology; Child; Child development; Children; Communication; Corpus callosum; Diffusion Magnetic Resonance Imaging; Female; fixel based analysis; Humans; Male; Motor task performance; PANESS; Pyramidal tracts; Pyramidal Tracts - diagnostic imaging; Pyramidal Tracts - pathology; Pyramidal Tracts - physiopathology; Substantia alba; subtle motor signs; white matter; White Matter - diagnostic imaging; White Matter - pathology; fixel based analysis; ADHD; subtle motor signs; white matter; PANESS
• DOI: 10.1002/hbm.70002
• ISSN: 1065-9471; 1097-0193

Subtle motor signs are a common feature in children with attention‐deficit/hyperactivity disorder (ADHD). It has long been suggested that white matter abnormalities may be involved in their presentation, though no study has directly probed this question. The aim of this study was to investigate the relationship between white matter organization and the severity of subtle motor signs in children with and without ADHD. Participants were 92 children with ADHD aged between 8 and 12 years, and 185 typically developing controls. Subtle motor signs were examined using the Physical and Neurological Examination for Soft Signs (PANESS). Children completed diffusion MRI, and fixel‐based analysis was performed after preprocessing. Tracts of interest were delineated using TractSeg including the corpus callosum (CC), the bilateral corticospinal tracts (CST), superior longitudinal fasciculus, and fronto‐pontine tracts (FPT). Fiber cross‐section (FC) was calculated for each tract. Across all participants, lower FC in the CST was associated with higher PANESS Total score (greater motor deficits). Within the PANESS, similar effects were observed for Timed Left and Right maneuvers of the hands and feet, with lower FC of the CST, CC, and FPT associated with poorer performance. No significant group differences were observed in FC in white matter regions associated with PANESS performance. Our data are consistent with theoretical accounts implicating white matter organization in the expression of motor signs in childhood. However, rather than contributing uniquely to the increased severity of soft motor signs in those with ADHD, white matter appears to contribute to these symptoms in childhood in general. Our data are consistent with theoretical accounts implicating white matter organization in the expression of motor signs in childhood. However, rather than contributing uniquely to the increased severity of soft motor signs in those with attention‐deficit/hyperactivity disorder, white matter appears to contribute to these symptoms in childhood in general.