Predicting odor perception: Modeling the relationship between brain activity, sympathetic nerve activity, and subjective evaluation for artificial organoleptic test

Research Project

Project/Area Number	17K12767
Research Category	Grant-in-Aid for Young Scientists (B)
Allocation Type	Multi-year Fund
Research Field	Kansei informatics
Research Institution	Hiroshima University
Principal Investigator	Soh Zu 広島大学, 工学研究科, 助教 (80724351)
Project Period (FY)	2017-04-01 – 2020-03-31
Project Status	Completed (Fiscal Year 2019)
Budget Amount *help	¥4,160,000 (Direct Cost: ¥3,200,000、Indirect Cost: ¥960,000) Fiscal Year 2019: ¥910,000 (Direct Cost: ¥700,000、Indirect Cost: ¥210,000) Fiscal Year 2018: ¥1,300,000 (Direct Cost: ¥1,000,000、Indirect Cost: ¥300,000) Fiscal Year 2017: ¥1,950,000 (Direct Cost: ¥1,500,000、Indirect Cost: ¥450,000)
Keywords	感性情報学 / 感性計測評価 / 匂い / 生体信号 / fMRI
Outline of Final Research Achievements	In this study, we aim to construct an artificial sensory test algorithm that can predict the subjective evaluation index obtained from a questionnaire for odor stimuli. We have achieved the following outcomes by combining olfactory system models and biological signal measurement techniques that we had developed. The following research results were obtained by using it. (1) It was clarified that the peripheral sympathetic nerve activity sensitively responds to odor stimuli than the sympathetic nerve activity of the heart. (2) fMRI measurement identified activated voxels with a significant difference in cerebral blood flow between unpleasant odor and pleasant odor with respect to resting cerebral blood flow. (3) It was shown that human subjective evaluation indices can be predicted to some extent from the glomerular activity of rat olfactory bulb. (4) It was shown that the peripheral sympathetic nerve activity index can be regressed to the subjective valence evaluation of humans.
Academic Significance and Societal Importance of the Research Achievements	研究代表者らの研究グループで独自に開発した対数線形化血管剛性指標は，末梢の自律神経活動を評価できるという心拍変動解析にはない利点がある．匂い刺激が末梢自律神経活動に与える影響を世界で初めて明らかにできた点に本研究成果の学術的意義がある．また，匂い固有の活動パターンが現れる嗅球は，骨や空洞の近くに位置するためfMRIによる活動の計測は困難である．ラットの嗅球活動から匂いに対する人間の快・不快が予測できる可能性を示した本研究成果は，今後高次脳までの脳活動をシミュレート可能なモデルの構築に展開できるという学術的意義がある．