title: Neuropharmacological effect of methylphenidate on attention network in children with attention deficit hyperactivity disorder during oddball paradigms as assessed using functional near-infrared spectroscopy.
abstract: The current study aimed to explore the neural substrate for methylphenidate effects on attentional control in school-aged children with attention deficit hyperactivity disorder (ADHD) using functional near-infrared spectroscopy (fNIRS), which can be applied to young children with ADHD more easily than conventional neuroimaging modalities. Using fNIRS, we monitored the oxy-hemoglobin signal changes of 22 ADHD children (6 to 14 years old) performing an oddball task before and 1.5 h after methylphenidate or placebo administration, in a randomized, double-blind, placebo-controlled, crossover design. Twenty-two age- and gender-matched normal controls without methylphenidate administration were also monitored. In the control subjects, the oddball task recruited the right prefrontal and inferior parietal cortices, and this activation was absent in premedicated ADHD children. The reduced right prefrontal activation was normalized after methylphenidate but not placebo administration in ADHD children. These results are consistent with the neuropharmacological effects of methylphenidate to upregulate the dopamine system in the prefrontal cortex innervating from the ventral tegmentum (mesocortical pathway), but not the noradrenergic system from the parietal cortex to the locus coeruleus. Thus, right prefrontal activation would serve as an objective neurofunctional biomarker to indicate the effectiveness of methylphenidate on ADHD children in attentional control. fNIRS monitoring enhances early clinical diagnosis and the treatment of ADHD children, especially those with an inattention phenotype.
authors.affiliation: Jichi Medical University , Department of Pediatrics, 3311-1 Yakushiji, Shimotsuke, Tochigi 329-0498, Japan.
authors.forename: Masako
authors.initials: M
authors.lastname: Nagashima
authors.affiliation: Jichi Medical University , Department of Pediatrics, 3311-1 Yakushiji, Shimotsuke, Tochigi 329-0498, Japan.
authors.forename: Yukifumi
authors.initials: Y
authors.lastname: Monden
authors.affiliation: Jichi Medical University , Department of Neurosurgery, 3311-1 Yakushiji, Shimotsuke, Tochigi 329-0498, Japan ; Chuo University , Applied Cognitive Neuroscience Laboratory, 1-13-27 Kasuga, Bunkyo, Tokyo 112-8551, Japan.
authors.forename: Ippeita
authors.initials: I
authors.lastname: Dan
authors.affiliation: Jichi Medical University , Department of Neurosurgery, 3311-1 Yakushiji, Shimotsuke, Tochigi 329-0498, Japan.
authors.forename: Haruka
authors.initials: H
authors.lastname: Dan
authors.affiliation: Chuo University , Applied Cognitive Neuroscience Laboratory, 1-13-27 Kasuga, Bunkyo, Tokyo 112-8551, Japan.
authors.forename: Daisuke
authors.initials: D
authors.lastname: Tsuzuki
authors.affiliation: Jichi Medical University , Department of Pediatrics, 3311-1 Yakushiji, Shimotsuke, Tochigi 329-0498, Japan ; Jichi Medical University , Functional Brain Science Laboratory, 3311-1 Yakushiji, Shimotsuke, Tochigi 329-0498, Japan.
authors.forename: Tsutomu
authors.initials: T
authors.lastname: Mizutani
authors.affiliation: Chuo University , Applied Cognitive Neuroscience Laboratory, 1-13-27 Kasuga, Bunkyo, Tokyo 112-8551, Japan.
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Kyutoku
authors.affiliation: Jichi Medical University , Department of Pediatrics, 3311-1 Yakushiji, Shimotsuke, Tochigi 329-0498, Japan ; International University of Health and Welfare , Department of Pediatrics, 537-3 Iguchi, Nasushiobara, Tochigi 329-2763, Japan.
authors.forename: Yuji
authors.initials: Y
authors.lastname: Gunji
authors.affiliation: International University of Health and Welfare , Department of Pediatrics, 537-3 Iguchi, Nasushiobara, Tochigi 329-2763, Japan.
authors.forename: Mariko Y
authors.initials: MY
authors.lastname: Momoi
authors.affiliation: Jichi Medical University , Department of Neurosurgery, 3311-1 Yakushiji, Shimotsuke, Tochigi 329-0498, Japan.
authors.forename: Eiju
authors.initials: E
authors.lastname: Watanabe
authors.affiliation: Jichi Medical University , Department of Pediatrics, 3311-1 Yakushiji, Shimotsuke, Tochigi 329-0498, Japan.
authors.forename: Takanori
authors.initials: T
authors.lastname: Yamagata
keywords: cortical hemodynamics; developmental disorder; dorsolateral prefrontal cortex; optical topography; target detection; ventrolateral prefrontal cortex