title: Effect of Transcranial Direct Current Stimulation over the Primary Motor Cortex on Cerebral Blood Flow: A Time Course Study Using Near-infrared Spectroscopy.
abstract: Transcranial direct current stimulation (tDCS) is a noninvasive brain stimulation technique that is applied during stroke rehabilitation. The purpose of this study was to examine diachronic intracranial hemodynamic changes using near-infrared spectroscopy (NIRS) during tDCS applied to the primary motor cortex (M1). Seven healthy volunteers were tested during real stimulation (anodal and cathodal) and during sham stimulation. Stimulation lasted 20 min and NIRS data were collected for about 23 min including the baseline. NIRS probe holders were positioned over the entire contralateral sensory motor area. Compared to the sham condition, both anodal and cathodal stimulation resulted in significantly lower oxyhemoglobin (O2Hb) concentrations in the contralateral premotor cortex (PMC), supplementary motor area (SMA), and M1 (p<0.01). Particularly in the SMA, the O2Hb concentration during anodal stimulation was significantly lower than that during the sham condition (p<0.01), while the O2Hb concentration during cathodal stimulation was lower than that during anodal stimulation (p<0.01). In addition, in the primary sensory cortex, the O2Hb concentration during anodal stimulation was significantly higher than the concentrations during both cathodal stimulation and the sham condition (p<0.05). The factor of time did not demonstrate significant differences. These results suggest that both anodal and cathodal tDCS cause widespread changes in cerebral blood flow, not only in the area immediately under the electrode, but also in other areas of the cortex.
authors.affiliation: Institute for Human Movement and Medical Sciences, Niigata University of Health and Welfare, 1398 Shimami-cho, Kita-ku, Niigata-shi, Niigata, 950-3198, Japan. hpm13005@nuhw.ac.jp.
authors.forename: Haruna
authors.initials: H
authors.lastname: Takai
authors.affiliation: Institute for Human Movement and Medical Sciences, Niigata University of Health and Welfare, 1398 Shimami-cho, Kita-ku, Niigata-shi, Niigata, 950-3198, Japan.
authors.forename: Atsuhiro
authors.initials: A
authors.lastname: Tsubaki
authors.affiliation: Institute for Human Movement and Medical Sciences, Niigata University of Health and Welfare, 1398 Shimami-cho, Kita-ku, Niigata-shi, Niigata, 950-3198, Japan.
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Sugawara
authors.affiliation: Institute for Human Movement and Medical Sciences, Niigata University of Health and Welfare, 1398 Shimami-cho, Kita-ku, Niigata-shi, Niigata, 950-3198, Japan.
authors.forename: Shota
authors.initials: S
authors.lastname: Miyaguchi
authors.affiliation: Kobe City Medical Center General Hospital, 2-2-1, Minatojimaminamimachi, Chuo-ku, Kobe, Hyogo, 650-0047, Japan.
authors.forename: Keiichi
authors.initials: K
authors.lastname: Oyanagi
authors.affiliation: Institute for Human Movement and Medical Sciences, Niigata University of Health and Welfare, 1398 Shimami-cho, Kita-ku, Niigata-shi, Niigata, 950-3198, Japan.
authors.forename: Takuya
authors.initials: T
authors.lastname: Matsumoto
authors.affiliation: Institute for Human Movement and Medical Sciences, Niigata University of Health and Welfare, 1398 Shimami-cho, Kita-ku, Niigata-shi, Niigata, 950-3198, Japan.
authors.forename: Hideaki
authors.initials: H
authors.lastname: Onishi
authors.affiliation: Niigata Rehabilitation Hospital, 761, Kizaki, Kita-ku, Niigata-shi, Niigata, 950-3304, Japan.
authors.forename: Noriaki
authors.initials: N
authors.lastname: Yamamoto
mesh_terms: D000328:Adult; D002560:Cerebrovascular Circulation; D006801:Humans; D009044:Motor Cortex / Q000502:physiology*; D010108:Oxyhemoglobins / Q000032:analysis; D019265:Spectroscopy, Near-Infrared / Q000379:methods*; D065908:Transcranial Direct Current Stimulation
chemical_list: D010108:Oxyhemoglobins
keywords: Near-infrared spectroscopy; Oxyhemoglobin; Primary motor area; Time course study; Transcranial direct current stimulation