title: Effects of transcranial direct current stimulation of the motor cortex on prefrontal cortex activation during a neuromuscular fatigue task: an fNIRS study.
abstract: This study investigated whether manipulation of motor cortex excitability by transcranial direct current stimulation (tDCS) modulates neuromuscular fatigue and functional near-infrared spectroscopy (fNIRS)-derived prefrontal cortex (PFC) activation. Fifteen healthy men (27.7 ± 8.4 years) underwent anodal (2 mA, 10 min) and sham (2 mA, first 30 s only) tDCS delivered to the scalp over the right motor cortex. Subjects initially performed a baseline sustained submaximal (30 % maximal voluntary isometric contraction, MVC) isometric contraction task (SSIT) of the left elbow flexors until task failure, which was followed 50 min later by either an anodal or sham treatment condition, then a subsequent posttreatment SSIT. Endurance time (ET), torque integral (TI), and fNIRS-derived contralateral PFC oxygenated (O2Hb) and deoxygenated (HHb) hemoglobin concentration changes were determined at task failure. Results indicated that during the baseline and posttreatment SSIT, there were no significant differences in TI and ET, and increases in fNIRS-derived PFC activation at task failure were observed similarly regardless of the tDCS conditions. This suggests that the PFC neuronal activation to maintain muscle force production was not modulated by anodal tDCS.
authors.affiliation: Movement to Health (M2H) Laboratory, Euromov, Montpellier-1 University, Montpellier, France. makii.muthalib@gmail.com.|School of Exercise and Health Sciences, Edith Cowan University, Perth, Australia. makii.muthalib@gmail.com.|Movement Neuroscience Program, Queensland University of Technology, Brisbane, Australia. makii.muthalib@gmail.com.
authors.forename: Makii
authors.initials: M
authors.lastname: Muthalib
authors.affiliation: School of Exercise and Health Sciences, Edith Cowan University, Perth, Australia.
authors.forename: Benjamin
authors.initials: B
authors.lastname: Kan
authors.affiliation: School of Exercise and Health Sciences, Edith Cowan University, Perth, Australia.
authors.forename: Kazunori
authors.initials: K
authors.lastname: Nosaka
authors.affiliation: Movement to Health (M2H) Laboratory, Euromov, Montpellier-1 University, Montpellier, France.
authors.forename: Stephane
authors.initials: S
authors.lastname: Perrey
mesh_terms: D000328:Adult; D004550:Elbow / Q000502:physiology; D005221:Fatigue / Q000378:metabolism / Q000503:physiopathology*; D006454:Hemoglobins / Q000378:metabolism; D006801:Humans; D007537:Isometric Contraction / Q000502:physiology; D008297:Male; D009044:Motor Cortex / Q000378:metabolism / Q000502:physiology*; D009469:Neuromuscular Junction / Q000378:metabolism / Q000502:physiology*; D010108:Oxyhemoglobins / Q000378:metabolism; D017397:Prefrontal Cortex / Q000378:metabolism / Q000502:physiology*; D011597:Psychomotor Performance / Q000502:physiology; D019265:Spectroscopy, Near-Infrared; D050781:Transcranial Magnetic Stimulation / Q000379:methods
chemical_list: D006454:Hemoglobins; D010108:Oxyhemoglobins; C100003:deoxyhemoglobin