title: Increased oxygen load in the prefrontal cortex from mouth breathing: a vector-based near-infrared spectroscopy study.
abstract: Individuals who habitually breathe through the mouth are more likely than nasal breathers to have sleep disorders and attention deficit hyperactive disorder. We hypothesized that brain hemodynamic responses in the prefrontal cortex might be different for mouth and nasal breathing. To test this hypothesis, we measured changes in oxyhemoglobin and deoxyhemoglobin in the prefrontal cortex during mouth breathing and nasal breathing in healthy adults (n=9) using vector-based near-infrared spectroscopy. The angle k, calculated from changes in oxyhemoglobin and deoxyhemoglobin and indicating the degree of oxygen exchange, was significantly higher during mouth breathing (P<0.05), indicating an increased oxygen load. Mouth breathing also caused a significant increase in deoxyhemoglobin, but oxyhemoglobin did not increase. This difference in oxygen load in the brain arising from different breathing routes can be evaluated quantitatively using vector-based near-infrared spectroscopy. Phase responses could help to provide an earlier and more reliable diagnosis of a patient's habitual breathing route than a patient interview.
authors.affiliation: aFamily Dental Clinic, Chitokukai Medical Association bDepartment of Brain Environmental Research, KatoBrain Co. Ltd, Tokyo, Japan.
authors.forename: Masahiro
authors.initials: M
authors.lastname: Sano
authors.forename: Sayaka
authors.initials: S
authors.lastname: Sano
authors.forename: Noriyuki
authors.initials: N
authors.lastname: Oka
authors.forename: Kayoko
authors.initials: K
authors.lastname: Yoshino
authors.forename: Toshinori
authors.initials: T
authors.lastname: Kato
mesh_terms: D000328:Adult; D005260:Female; D006439:Hemodynamics; D006801:Humans; D008297:Male; D009058:Mouth Breathing / Q000378:metabolism*; D010101:Oxygen Consumption; D017397:Prefrontal Cortex / Q000378:metabolism*; D019265:Spectroscopy, Near-Infrared