Spatial and Temporal Brain Responses to Noxious Heat Thermal Stimuli in Burning Mouth Syndrome.
Burning mouth syndrome (BMS) is an idiopathic orofacial pain condition. Although the pathophysiology of BMS is not clearly understood, central and peripheral neuropathic mechanisms are thought to be involved. The authors compared brain response to noxious heat stimuli in 16 right-handed women with primary BMS and 15 sex- and age-matched right-handed healthy female controls. A thermal stimulus sequence of 32 °C to 40 °C to 32 °C to 49 °C was repeated 4 times in a cycle. Warm and noxious heat stimuli were delivered with a Peltier thermode placed on the right palm or right lower lip for 32 s each in a session. Functional magnetic resonance imaging data were obtained by recording echoplanar images with a block design. Statistical Parametric Mapping 8 software was used to analyze the data. Patients and controls both reported feeling more pain during palm stimulation than during lip stimulation. Repetition of noxious heat stimulus on the lower lip but not on the palm induced habituation in brain activity in the cingulate cortex without reduction in pain perception. Multiple regression analysis revealed a correlation between perceived pain intensity and suppression of brain activity in the anterior cingulate cortex when the repeated thermal sequence was applied at the lower lip. Furthermore, the response of the parahippocampal area differed in BMS patients and controls when the same repeated thermal sequence was applied at the palm. The authors' findings indicate that BMS patients show specific brain responses due to impaired function of the central and peripheral nervous systems (clinical trial registration: UMIN000015002).
Department of Oral Diagnostic Sciences, Nihon University School of Dentistry, Tokyo, Japan Clinical Research Division, Nihon University Dental Research Center, Tokyo, Japan.
T
T
Shinozaki
Department of Oral Diagnostic Sciences, Nihon University School of Dentistry, Tokyo, Japan Clinical Research Division, Nihon University Dental Research Center, Tokyo, Japan imamura.yoshiki@nihon-u.ac.jp.
Y
Y
Imamura
Department of Oral Diagnostic Sciences, Nihon University School of Dentistry, Tokyo, Japan.
R
R
Kohashi
Department of Oral Diagnostic Sciences, Nihon University School of Dentistry, Tokyo, Japan.
K
K
Dezawa
Department of Oral Diagnostic Sciences, Nihon University School of Dentistry, Tokyo, Japan.
Y
Y
Nakaya
Department of Oral Diagnostic Sciences, Nihon University School of Dentistry, Tokyo, Japan.
Y
Y
Sato
Department of Oral Diagnostic Sciences, Nihon University School of Dentistry, Tokyo, Japan.
K
K
Watanabe
Division of Oral and Maxillofacial Radiology, Kyushu Dental University, Kitakyushu, Japan.
Y
Y
Morimoto
Department of Radiology, Nihon University School of Medicine, Tokyo, Japan.
T
T
Shizukuishi
Department of Radiology, Nihon University School of Medicine, Tokyo, Japan.
O
O
Abe
Brain Activity Imaging Center, ATR-Promotions Inc., Osaka, Japan.
T
T
Haji
Department of Dementia Prevention and Therapeutics, Mie University Graduate School of Medicine, Tsu, Japan.
K
K
Tabei
Department of Cognitive Neurobiology, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan Center for Brain Integration Research, Tokyo Medical and Dental University, Tokyo, Japan.
M
M
Taira
D000328:Adult; D001931:Brain Mapping / Q000379:methods*; D002054:Burning Mouth Syndrome / Q000503:physiopathology*; D016022:Case-Control Studies; D005260:Female; D006179:Gyrus Cinguli / Q000503:physiopathology; D006225:Hand; D006624:Hippocampus / Q000503:physiopathology; D006358:Hot Temperature; D006801:Humans; D007090:Image Interpretation, Computer-Assisted; D008046:Lip; D008279:Magnetic Resonance Imaging; D008875:Middle Aged; D010147:Pain Measurement; D058748:Pain Perception / Q000502:physiology
anterior cingulate cortex; chronic primary pain; functional MRI; neuropathic orofacial pain; pain habituation; parahippocampal gyrus