Nakamura Yuko, Goto Tazuko K, Tokumori Kenji, Yoshiura Takashi, Kobayashi Koji, Nakamura Yasuhiko, Honda Hiroshi, Ninomiya Yuzo, Yoshiura Kazunori
Department of Oral and Maxillofacial Radiology, Faculty of Dental Science, Kyushu University, Fukuoka, Japan.
Neuroreport. 2012 Apr 18;23(6):400-4. doi: 10.1097/WNR.0b013e32835271b7.
It remains unclear how the cerebral cortex of humans perceives taste temporally, and whether or not such objective data about the brain show a correlation with the current widely used conventional methods of taste-intensity sensory evaluation. The aim of this study was to investigate the difference in the time-intensity profile between salty and sweet tastes in the human brain. The time-intensity profiles of functional MRI (fMRI) data of the human taste cortex were analyzed using finite impulse response analysis for a direct interpretation in terms of the peristimulus time signal. Also, time-intensity sensory evaluations for tastes were performed under the same condition as fMRI to confirm the reliability of the temporal profile in the fMRI data. The time-intensity profile for the brain activations due to a salty taste changed more rapidly than those due to a sweet taste in the human brain cortex and was also similar to the time-intensity sensory evaluation, confirming the reliability of the temporal profile of the fMRI data. In conclusion, the time-intensity profile using finite impulse response analysis for fMRI data showed that there was a temporal difference in the neural responses between salty and sweet tastes over a given period of time. This indicates that there might be taste-specific temporal profiles of activations in the human brain.
目前尚不清楚人类大脑皮层如何在时间上感知味觉，以及关于大脑的此类客观数据是否与当前广泛使用的传统味觉强度感官评估方法存在相关性。本研究的目的是调查人类大脑中咸味和甜味之间时间强度曲线的差异。使用有限脉冲响应分析对人类味觉皮层的功能磁共振成像（fMRI）数据的时间强度曲线进行分析，以便根据刺激时间信号进行直接解读。此外，在与fMRI相同的条件下对味觉进行时间强度感官评估，以确认fMRI数据中时间曲线的可靠性。在人类大脑皮层中，咸味引起的大脑激活的时间强度曲线比甜味引起的变化更快，并且也与时间强度感官评估相似，这证实了fMRI数据时间曲线的可靠性。总之，对fMRI数据使用有限脉冲响应分析得到的时间强度曲线表明，在给定时间段内，咸味和甜味的神经反应在时间上存在差异。这表明人类大脑中可能存在特定味觉的激活时间曲线。
