title: Bimanual coordination of force enhances interhemispheric inhibition between the primary motor cortices.
abstract: The purpose of this study was to elucidate whether bimanual coordination of force affects interhemispheric inhibition (IHI) between the primary motor cortices (M1s). IHI with the index fingers isometrically abducted against a fixed plate (AAP task) was compared with IHI with the index fingers isometrically abducted against each other (AAF task). The index fingers were held stationary at the midline and activity levels of the first dorsal interosseous muscles were equalized between the tasks. The abduction force of each index finger was individually controlled during the AAP task, and bimanually coordinated during the AAF task. IHI during the AAF task was significantly higher than that during the AAP task. IHI between the M1s is related not only to the suppression of unwanted activity of the M1 contralateral to the active M1 but also to bimanual coordination of force.
authors.affiliation: aCollege of Health and Human Sciences bGraduate School of Comprehensive Rehabilitation, Osaka Prefecture University, Habikino, Osaka, Japan.
authors.forename: Koichi
authors.initials: K
authors.lastname: Hiraoka
authors.forename: Minori
authors.initials: M
authors.lastname: Ae
authors.forename: Nana
authors.initials: N
authors.lastname: Ogura
authors.forename: Chisa
authors.initials: C
authors.lastname: Sano
authors.forename: Keigo
authors.initials: K
authors.lastname: Shiomi
authors.forename: Yuji
authors.initials: Y
authors.lastname: Morita
authors.forename: Haruka
authors.initials: H
authors.lastname: Yokoyama
authors.forename: Yasutomo
authors.initials: Y
authors.lastname: Jono
authors.forename: Yoshifumi
authors.initials: Y
authors.lastname: Nomura
authors.forename: Keisuke
authors.initials: K
authors.lastname: Tani
authors.forename: Yuta
authors.initials: Y
authors.lastname: Chujo
mesh_terms: D004576:Electromyography; D019054:Evoked Potentials, Motor; D005260:Female; D005385:Fingers / Q000502:physiology*; D007839:Functional Laterality / Q000502:physiology; D006801:Humans; D007537:Isometric Contraction / Q000502:physiology; D008297:Male; D009044:Motor Cortex / Q000502:physiology*; D018482:Muscle, Skeletal / Q000502:physiology; D009433:Neural Inhibition / Q000502:physiology*; D011597:Psychomotor Performance / Q000502:physiology*; D050781:Transcranial Magnetic Stimulation; D055815:Young Adult