title: Right prefrontal activation as a neuro-functional biomarker for monitoring acute effects of methylphenidate in ADHD children: An fNIRS study.
abstract: An objective biomarker is a compelling need for the early diagnosis of attention deficit hyperactivity disorder (ADHD), as well as for the monitoring of pharmacological treatment effectiveness. The advent of fNIRS, which is relatively robust to the body movements of ADHD children, raised the possibility of introducing functional neuroimaging diagnosis in younger ADHD children. Using fNIRS, we monitored the oxy-hemoglobin signal changes of 16 ADHD children (6 to 13 years old) performing a go/no-go task before and 1.5 h after MPH or placebo administration, in a randomized, double-blind, placebo-controlled, crossover design. 16 age- and gender-matched normal controls without MPH administration were also monitored. Relative to control subjects, unmedicated ADHD children exhibited reduced activation in the right inferior frontal gyrus (IFG) and middle frontal gyrus (MFG) during go/no-go tasks. The reduced right IFG/MFG activation was acutely normalized after MPH administration, but not after placebo administration. The MPH-induced right IFG/MFG activation was significantly larger than the placebo-induced activation. Post-scan exclusion rate was 0% among 16 right-handed ADHD children with IQ > 70. We revealed that the right IFG/MFG activation could serve as a neuro-functional biomarker for monitoring the acute effects of methylphenidate in ADHD children. fNIRS-based examinations were applicable to ADHD children as young as 6 years old, and thus would contribute to early clinical diagnosis and treatment of ADHD children.
authors.affiliation: Department of Pediatrics, Jichi Medical University, 3311-1 Yakushiji, Shimotsuke, Tochigi 329-0498, Japan ; Department of Pediatrics, International University of Health and Welfare, 537-3 Iguchi, Shiobara, Tochigi 329-2763, Japan.
authors.forename: Yukifumi
authors.initials: Y
authors.lastname: Monden
authors.forename: Haruka
authors.initials: H
authors.lastname: Dan
authors.forename: Masako
authors.initials: M
authors.lastname: Nagashima
authors.forename: Ippeita
authors.initials: I
authors.lastname: Dan
authors.forename: Daisuke
authors.initials: D
authors.lastname: Tsuzuki
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Kyutoku
authors.forename: Yuji
authors.initials: Y
authors.lastname: Gunji
authors.forename: Takanori
authors.initials: T
authors.lastname: Yamagata
authors.forename: Eiju
authors.initials: E
authors.lastname: Watanabe
authors.forename: Mariko Y
authors.initials: MY
authors.lastname: Momoi
keywords: Cortical hemodynamics; Developmental disorder; Dorsolateral prefrontal cortex; Optical topography; Ventrolateral prefrontal cortex