title: Facial vibrotactile stimulation activates the parasympathetic nervous system: study of salivary secretion, heart rate, pupillary reflex, and functional near-infrared spectroscopy activity.
abstract: We previously found that the greatest salivation response in healthy human subjects is produced by facial vibrotactile stimulation of 89 Hz frequency with 1.9 μ m amplitude (89 Hz-S), as reported by Hiraba et al. (2012, 20011, and 2008). We assessed relationships between the blood flow to brain via functional near-infrared spectroscopy (fNIRS) in the frontal cortex and autonomic parameters. We used the heart rate (HRV: heart rate variability analysis in RR intervals), pupil reflex, and salivation as parameters, but the interrelation between each parameter and fNIRS measures remains unknown. We were to investigate the relationship in response to established paradigms using simultaneously each parameter-fNIRS recording in healthy human subjects. Analysis of fNIRS was examined by a comparison of various values between before and after various stimuli (89 Hz-S, 114 Hz-S, listen to classic music, and "Ahh" vocalization). We confirmed that vibrotactile stimulation (89 Hz) of the parotid glands led to the greatest salivation, greatest increase in heart rate variability, and the most constricted pupils. Furthermore, there were almost no detectable differences between fNIRS during 89 Hz-S and fNIRS during listening to classical music of fans. Thus, vibrotactile stimulation of 89 Hz seems to evoke parasympathetic activity.
authors: Department of Dysphasia Rehabilitation, Nihon University of Dentistry, 1-8-13 Kanda-surugadai, Chiyoda-ku, Tokyo 101-8310, Japan.
authors: Hisao
authors: H
authors: Hiraba
authors: Department of Dysphasia Rehabilitation, Nihon University of Dentistry, 1-8-13 Kanda-surugadai, Chiyoda-ku, Tokyo 101-8310, Japan.
authors: Motoharu
authors: M
authors: Inoue
authors: Department of Dysphasia Rehabilitation, Nihon University of Dentistry, 1-8-13 Kanda-surugadai, Chiyoda-ku, Tokyo 101-8310, Japan.
authors: Kanako
authors: K
authors: Gora
authors: Department of 1st Oral and Maxillofacial Surgery, Nihon University of Dentistry, 1-8-13 Kanda-surugadai, Chiyoda-ku, Tokyo 101-8310, Japan.
authors: Takako
authors: T
authors: Sato
authors: Department of 1st Oral and Maxillofacial Surgery, Nihon University of Dentistry, 1-8-13 Kanda-surugadai, Chiyoda-ku, Tokyo 101-8310, Japan.
authors: Satoshi
authors: S
authors: Nishimura
authors: Department of Physics, Nihon University of Dentistry, 1-8-13 Kanda-surugadai, Chiyoda-ku, Tokyo 101-8310, Japan.
authors: Masaru
authors: M
authors: Yamaoka
authors: Department of Dysphasia Rehabilitation, Nihon University of Dentistry, 1-8-13 Kanda-surugadai, Chiyoda-ku, Tokyo 101-8310, Japan.
authors: Ayano
authors: A
authors: Kumakura
authors: Department of Dysphasia Rehabilitation, Nihon University of Dentistry, 1-8-13 Kanda-surugadai, Chiyoda-ku, Tokyo 101-8310, Japan.
authors: Shinya
authors: S
authors: Ono
authors: Department of Dysphasia Rehabilitation, Nihon University of Dentistry, 1-8-13 Kanda-surugadai, Chiyoda-ku, Tokyo 101-8310, Japan.
authors: Hirotugu
authors: H
authors: Wakasa
authors: Department of Dysphasia Rehabilitation, Nihon University of Dentistry, 1-8-13 Kanda-surugadai, Chiyoda-ku, Tokyo 101-8310, Japan.
authors: Enri
authors: E
authors: Nakayama
authors: Department of Dysphasia Rehabilitation, Nihon University of Dentistry, 1-8-13 Kanda-surugadai, Chiyoda-ku, Tokyo 101-8310, Japan.
authors: Kimiko
authors: K
authors: Abe
authors: Department of Dysphasia Rehabilitation, Nihon University of Dentistry, 1-8-13 Kanda-surugadai, Chiyoda-ku, Tokyo 101-8310, Japan.
authors: Koichiro
authors: K
authors: Ueda
mesh_terms: D000328:Adult; D005260:Female; D005625:Frontal Lobe / Q000098:blood supply; D006339:Heart Rate / Q000502:physiology*; D006801:Humans; D008297:Male; D010108:Oxyhemoglobins / Q000032:analysis; D010275:Parasympathetic Nervous System / Q000502:physiology; D010812:Physical Stimulation / Q000379:methods*; D012025:Reflex, Pupillary / Q000502:physiology*; D012472:Salivation / Q000502:physiology*; D019265:Spectroscopy, Near-Infrared; D014732:Vibration / Q000627:therapeutic use*; D055815:Young Adult
chemical_list: D010108:Oxyhemoglobins