title: Prefrontal Hemodynamic Changes Associated with Subjective Sense of Occlusal Discomfort.
abstract: We used functional near-infrared spectroscopy to measure prefrontal brain activity accompanying the physical sensation of oral discomfort that arose when healthy young-adult volunteers performed a grinding motion with mild occlusal elevation (96 μm). We simultaneously evaluated various forms of occlusal discomfort using the visual analogue scale (VAS) and hemodynamic responses to identify the specific prefrontal activity that occurs with increased occlusal discomfort. The Oxy-Hb responses of selected channels in the bilateral frontopolar and dorsolateral prefrontal cortices increased in participants who reported increased severity of occlusal discomfort, while they decreased in those who reported no change or decreased occlusal discomfort during grinding. Moreover, the cumulative values of Oxy-Hb response in some of these channels were statistically significant predictive factors for the VAS scores. A generalized linear model analysis of Oxy-Hb signals in a group of participants who reported increased discomfort further indicated significant cerebral activation in the right frontopolar and dorsolateral prefrontal cortices that overlapped with the results of correlation analyses. Our results suggest that the increased hemodynamic responses in the prefrontal area reflect the top-down control of attention and/or self-regulation against the uncomfortable somatosensory input, which could be a possible marker to detect the subjective sense of occlusal discomfort.
authors.affiliation: Health Science and Medical Engineering Laboratory, Department of Electronics and Bioinformatics, School of Science and Technology, Meiji University, Room A806, 1-1-1 Higashi-Mita, Tama-ku, Kawasaki, Kanagawa 214-8571, Japan.
authors.forename: Yumie
authors.identifier: 0000-0002-2176-4312
authors.initials: Y
authors.lastname: Ono
authors.affiliation: Department of Prosthodontic Dentistry for Function of TMJ and Occlusion, Kanagawa Dental University, 82 Inaoka-cho, Yokosuka, Kanagawa 238-8869, Japan.
authors.forename: Goh
authors.initials: G
authors.lastname: Kobayashi
authors.affiliation: Department of Prosthodontic Dentistry for Function of TMJ and Occlusion, Kanagawa Dental University, 82 Inaoka-cho, Yokosuka, Kanagawa 238-8869, Japan.
authors.forename: Rika
authors.initials: R
authors.lastname: Hayama
authors.affiliation: Department of Prosthodontic Dentistry for Function of TMJ and Occlusion, Kanagawa Dental University, 82 Inaoka-cho, Yokosuka, Kanagawa 238-8869, Japan.
authors.forename: Ryuhei
authors.initials: R
authors.lastname: Ikuta
authors.affiliation: Department of Judo Therapy and Medical Science, Faculty of Medical Science, Nippon Sport Science University, 1221-1 Kamoshida-cho, Aoba-ku, Yokohama 227-0033, Japan.
authors.forename: Minoru
authors.initials: M
authors.lastname: Onozouka
authors.affiliation: Department of Prosthodontic Dentistry for Function of TMJ and Occlusion, Kanagawa Dental University, 82 Inaoka-cho, Yokosuka, Kanagawa 238-8869, Japan.
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Wake
authors.affiliation: Department of Prosthodontic Dentistry for Function of TMJ and Occlusion, Kanagawa Dental University, 82 Inaoka-cho, Yokosuka, Kanagawa 238-8869, Japan.
authors.forename: Atsushi
authors.initials: A
authors.lastname: Shimada
authors.affiliation: Department of Prosthodontic Dentistry for Function of TMJ and Occlusion, Kanagawa Dental University, 82 Inaoka-cho, Yokosuka, Kanagawa 238-8869, Japan.
authors.forename: Tomoaki
authors.initials: T
authors.lastname: Shibuya
authors.affiliation: Department of Prosthodontic Dentistry for Function of TMJ and Occlusion, Kanagawa Dental University, 82 Inaoka-cho, Yokosuka, Kanagawa 238-8869, Japan.
authors.forename: Katsushi
authors.initials: K
authors.lastname: Tamaki
mesh_terms: D000328:Adult; D001931:Brain Mapping; D005260:Female; D006439:Hemodynamics; D006801:Humans; D008297:Male; D008875:Middle Aged; D019558:Occlusal Adjustment; D010108:Oxyhemoglobins / Q000378:metabolism*; D017397:Prefrontal Cortex / Q000378:metabolism / Q000503:physiopathology*; D019265:Spectroscopy, Near-Infrared
chemical_list: D010108:Oxyhemoglobins