White matter and sustained attention in children with attention/deficit-hyperactivity disorder: A longitudinal fixel-based analysis

Phoebe Thomson; Nandita Vijayakumar; Ian Fuelscher; Charles B Malpas; Philip Hazell; Timothy J Silk

doi:10.1016/j.cortex.2022.09.006

White matter and sustained attention in children with attention/deficit-hyperactivity disorder: A longitudinal fixel-based analysis

Cortex. 2022 Dec:157:129-141. doi: 10.1016/j.cortex.2022.09.006. Epub 2022 Oct 7.

Authors

Phoebe Thomson¹, Nandita Vijayakumar², Ian Fuelscher², Charles B Malpas³, Philip Hazell⁴, Timothy J Silk⁵

Affiliations

¹ Department of Paediatrics, The University of Melbourne, Melbourne, Australia; Murdoch Children's Research Institute, Melbourne, Australia. Electronic address: phoebethomsonc@gmail.com.
² School of Psychology, Deakin University, Melbourne, Australia.
³ Murdoch Children's Research Institute, Melbourne, Australia; Department of Medicine, Royal Melbourne Hospital, The University of Melbourne, Melbourne, Australia; Melbourne School of Psychological Sciences, The University of Melbourne, Melbourne, Australia.
⁴ Discipline of Psychiatry, The University of Sydney, Sydney, Australia.
⁵ Department of Paediatrics, The University of Melbourne, Melbourne, Australia; Murdoch Children's Research Institute, Melbourne, Australia; School of Psychology, Deakin University, Melbourne, Australia.

PMID: 36283135
DOI: 10.1016/j.cortex.2022.09.006

Abstract

Sustained attention is a cognitive function with known links to academic success and mental health disorders such as attention/deficit-hyperactivity disorder (ADHD). Several functional networks are critical to sustained attention, however the association between white matter maturation in tracts linking functional nodes and sustained attention in typical and atypical development is unknown. 309 diffusion-weighted imaging scans were acquired from 161 children and adolescents (80 ADHD, 81 control) at up to three timepoints over ages 9-14. A fixel-based analysis approach was used to calculate mean fiber density and fiber-bundle cross section in tracts of interest. Sustained attention was measured using omission errors and response time variability on the out-of-scanner sustained attention to response task. Linear mixed effects models examined associations of age, group and white matter metrics with sustained attention. Greater fiber density in the bilateral superior longitudinal fasciculus (SLF) I and right SLF II was associated with fewer attention errors in the control group only. In ADHD and control groups, greater fiber density in the left ILF and right thalamo-premotor pathway, as well as greater fiber cross-section in the left SLF I and II and right SLF III, was associated with better sustained attention. Relationships were consistent across the age span. Results suggest that greater axon diameter or number in the dorsal and middle SLF may facilitate sustained attention in neurotypical children but does not assist those with ADHD potentially due to disorder-related alterations in this region. Greater capacity for information transfer across the SLF was associated with attention maintenance in 9-14-year-olds regardless of diagnostic status, suggesting white matter macrostructure may also be important for attention maintenance. White matter and sustained attention associations were consistent across the longitudinal study, according with the stability of structural organization over this time. Future studies can investigate modifiability of white matter properties through ADHD medications.

Keywords: Attention/deficit-hyperactivity disorder; Diffusion MRI; Fixel-based analysis; Longitudinal; Sustained attention.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Adolescent
Attention Deficit Disorder with Hyperactivity*
Child
Diffusion Magnetic Resonance Imaging
Humans
Longitudinal Studies
Nerve Net
White Matter* / diagnostic imaging