title: Influence of voluntary control of masticatory side and rhythm on cerebral hemodynamics.
abstract: The aim of this study was to investigate the influence on cerebral hemodynamics of voluntary control of masticatory side and rhythm during gum chewing. Blood flow velocity in the middle cerebral artery was measured using transcranial Doppler ultrasonography to evaluate cerebral circulation in healthy volunteers. Heart rate and masseter muscle activity were recorded simultaneously. Volunteers performed three tasks: (1) free gum chewing, (2) gum chewing in which mastication was limited to the right side, and (3) gum chewing in which mastication was limited to the right side and rhythm was set at 1.0 Hz. Changes in cerebral circulation during pre-task, on-task, and post-task periods were analyzed using random effects model, and differences in cerebral circulation and muscle activity between tasks were analyzed using the Friedman test. In all tasks, on-task cerebral circulation was greater than pre-task. Muscle activity and masticatory rhythm varied between tasks, whereas the rate of increase in cerebral circulation did not differ significantly among tasks. These results suggest that cerebral circulation is activated during gum chewing, irrespective of voluntary control of masticatory side and rhythm.
authors.affiliation: Division of Oromaxillofacial Regeneration, Osaka University Graduate School of Dentistry, 1-8 Yamada-oka, Suita, Osaka, Japan.
authors.forename: Yoko
authors.initials: Y
authors.lastname: Hasegawa
authors.forename: Takahiro
authors.initials: T
authors.lastname: Ono
authors.forename: Joe
authors.initials: J
authors.lastname: Sakagami
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Hori
authors.forename: Yoshinobu
authors.initials: Y
authors.lastname: Maeda
authors.forename: Toshimitsu
authors.initials: T
authors.lastname: Hamasaki
authors.forename: Takashi
authors.initials: T
authors.lastname: Nokubi
mesh_terms: D000328:Adult; D001783:Blood Flow Velocity; D002560:Cerebrovascular Circulation / Q000502:physiology*; D002638:Chewing Gum; D004576:Electromyography; D005260:Female; D007839:Functional Laterality / Q000502:physiology*; D006339:Heart Rate; D006801:Humans; D008297:Male; D008406:Masseter Muscle / Q000502:physiology; D008409:Mastication / Q000502:physiology*; D020768:Middle Cerebral Artery; D015233:Models, Statistical; D018709:Statistics, Nonparametric; D017585:Ultrasonography, Doppler, Transcranial
chemical_list: D002638:Chewing Gum