title: Different neural substrates for executive functions in youths with ADHD: a diffusion spectrum imaging tractography study.
abstract: BACKGROUND
  The relationship between white-matter tracts and executive functions (EF) in attention deficit hyperactivity disorder (ADHD) has not been well studied and previous studies mainly focused on frontostriatal (FS) tracts. The authors explored the microstructural property of several fibre tracts hypothesized to be involved in EF, to correlate their microstructural property with EF, and to explore whether such associations differ between ADHD and typically developing (TD) youths.
  
  
  METHODS
  We assessed 45 youths with ADHD and 45 individually matched TD youths with a computerized test battery for multiple dimensions of EF. From magnetic resonance imaging, FS tract, superior longitudinal fasciculus (SLF), arcuate fasciculus (AF) and cingulum bundle (CB) were reconstructed by diffusion spectrum imaging tractography. The generalized fractional anisotropy (GFA) values of white-matter tracts were computed to present microstructural property of each tract.
  
  
  RESULTS
  We found lower GFA in the left FS tract, left SLF, left AF and right CB, and poorer performance in set-shifting, sustained attention, cognitive inhibition and visuospatial planning in ADHD than TD. The ADHD and TD groups demonstrated different association patterns between EF and fibre tract microstructural property. Most of the EF were associated with microstructural integrity of the FS tract and CB in TD youths, while with that of the FS tract, SLF and AF in youths with ADHD.
  
  
  CONCLUSIONS
  Our findings support that the SLF, AF and CB also involve in a wide range of EF and that the main fibre tracts involved in EF are different in youths with ADHD.
authors.affiliation: Department of Psychiatry,National Taiwan University Hospital and College of Medicine,Taipei,Taiwan.
authors.forename: H-L
authors.initials: HL
authors.lastname: Chiang
authors.affiliation: Institute of Medical Device and Imaging, National Taiwan University College of Medicine,Taipei,Taiwan.
authors.forename: Y-J
authors.initials: YJ
authors.lastname: Chen
authors.affiliation: Department of Psychiatry,National Taiwan University Hospital and College of Medicine,Taipei,Taiwan.
authors.forename: C-Y
authors.initials: CY
authors.lastname: Shang
authors.affiliation: Institute of Medical Device and Imaging, National Taiwan University College of Medicine,Taipei,Taiwan.
authors.forename: W-Y I
authors.initials: WY
authors.lastname: Tseng
authors.affiliation: Department of Psychiatry,National Taiwan University Hospital and College of Medicine,Taipei,Taiwan.
authors.forename: S S-F
authors.initials: SS
authors.lastname: Gau
mesh_terms: D000293:Adolescent; D016880:Anisotropy; D001288:Attention; D001289:Attention Deficit Disorder with Hyperactivity / Q000503:physiopathology*; D016022:Case-Control Studies; D002648:Child; D056324:Diffusion Tensor Imaging; D056344:Executive Function; D005260:Female; D006801:Humans; D016014:Linear Models; D008279:Magnetic Resonance Imaging; D008297:Male; D009415:Nerve Net / Q000503:physiopathology*; D009434:Neural Pathways / Q000503:physiopathology*; D013624:Taiwan; D066127:White Matter / Q000503:physiopathology*
keywords: Attention deficit hyperactivity disorder; diffusion spectrum imaging; executive function; tractography