Basic study on individual preference for scents and the arousal level for brain activity using MNIRS

In this study, seven kinds of scent were used as olfactory stimulation. The influence of scent on the driver´s psychosomatic state was examined using a fixed-based driving simulator by through biological measurements including electrocardiogram. Taste in scents is so individual that blood flow of brain activity is measured in order to estimate the reaction of scent on the subject. As for brain activity of olfactory cortex, the multi-channel near-infrared spectroscopy (MNIRS) has been shown to enable the evaluation of changes in hemodynamic. The MNIRS was also used to monitor the activity of the frontal cortex as mirrored by hemodynamic responses subjected to olfactory stimulation. The experiments were executed for several female and male subjects. The difference of reaction by sex is also observed. As a result, it is verified that not only characteristics of the scent but also the subject´s preference and subjective judgment of scent changes affect working performance. The effects of the scent on functional brain imaging were measured and the individual preference for scent was effective for maintaining the arousal level and the difference in reaction time was recognized according to gender.