An optimal umami taste stimulating system for brain mapping
Objectives: fMRI studies of taste tend to decrease specificity of the results by head movements associated with swallowing. The purpose of this study was to develop a new system that spreads taste stimuli on the dorsal surface of the tongue as widely as possible and also prevents swallowing to perform functional brain mapping of the umami taste sense.
Methods: The delivery system of taste solution consisted of an intra-oral and an extra-oral device. The intra-oral device was assembled with four solution-inlet tubes and an outlet tube that were attached to an individual mouthpiece. The outlet tube was connected to a continuous suction apparatus. Healthy volunteers (5 male and 3 female, age range 19-28 years) participated in this study. The Human Experimentation Committee of Kyushu University approved all experimental procedures. The taste stimulus was umami (0.1M monosodium L-glutamate and 0.005M inosine monophosphate), salty (0.1M sodium chloride), and a tasteless control solution containing the main ionic components of saliva (25 mM KCl plus 2.5 mM NaHCO3). All images were acquired with a whole-body 3.0-T MRI scanner. Image processing and data analysis were performed using the Statistical Parametric Mapping 5 software package (Wellcome Department of Cognitive Neurology, London, UK).
Results: This device delivered the taste solution on most of the dorsum part of the tongue and prevented swallowing. The head motions of all subjects were less than 1.5 mm in translation and less than 3.0 degrees in rotation in all sessions. The area activated by umami was located on the putative human primary taste cortex (uncorrected P < 0.001).
Conclusion: This intra-oral device stimulated the subject's tongue as much as possible under constant conditions, and suppressed each subject's head movements sufficiently. This system will make it possible to perform precise functional brain mapping of the taste cortex induced from the umami substance.
Division: Japanese Division Meeting
Meeting:2008 Japanese Division Meeting (Nagoya City, Japan) Location: Nagoya City, Japan
Year: 2008 Final Presentation ID: Abstract Category|Abstract Category(s):Scientific Groups
Authors
Nakamura, Yuko
( Kyushu University, Fukuoka, N/A, Japan
)
Goto, Tazuko
( Kyushu University, Fukuoka, N/A, Japan
)
Tokumori, K.
( Kyushu University, Fukuoka, N/A, Japan
)
Yoshiura, Takashi
( Department of Clinical Radiology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, N/A, Japan
)
Kobayashi, Koji
( Department of Medical Technology, Kyushu University, Fukuoka, N/A, Japan
)
Nakamura, Yasuhiko
( Department of Medical Technology, Kyushu University Hospital, Fukuoka, N/A, Japan
)
Honda, Hiroshi
( Department of Clinical Radiology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, N/A, Japan
)
Ninomiya, Yuzo
( Section of Oral Neuroscience, Graduate School of Dental Science, Kyushu University, Fukuoka, N/A, Japan
)
Yoshiura, Kazunori
( Kyushu University, Fukuoka, N/A, Japan
)