Influence of Initial Settings of Chaos Analysis on Fingertip Plethysmography for Evaluation of Emotions Induced by Exposure to Fragrance

Fragrance influences the psychophysiological state of a person; the volume of fingertip plethysmography is consequently affected by the aspiration of aroma. Further, it may make an individual uncomfortable depending on the amount of odor that they inhale. It has been reported that fingertip plethysmogram has a chaotic nature and is sensitive to pleasant and unpleasant emotions. Chaos analyses have demonstrated various significant findings: however, multiple setting values used in these analyses are arbitrarily determined and are not standard. Therefore, in this study, we compared the biometric index obtained by analyzing the fingertip plethysmogram through a fingertip volume pulse wave investigation. This was done by quantitatively flowing the scent directly into the nose and conducting a real-time subjective evaluation with the collaborators. Then, a suitable development time was examined. The Dynamic time warping (DTW) was used to compare the subjective evaluation and results of the analysis for various fingertip volume pulse waves. A most suitable development time was obtained based on the DTW results. The results suggested that emotions can be measured when an individual is exposed to fragrances.