Versatile Psychophysiological Potencies of Essential Oils, when Seen as a Function of Behavioral Task Assigned to the Participants after Inhalation

To elucidate the psychophysiological effect of inhaling essential oils, in this paper, we sought to assess the following 12 essential oils: basil, bergamot, cardamom, cinnamon, juniper, lemon, orange, palmarosa, peppermint, sandalwood, spearmint, and ylang ylang. As these being target odors, we focused on the verbal (semantic) and non-verbal (skin temperature) endpoints of the stimuli. In our experimental design, we managed to assign different behavioral tasks to the participants. The Uchida-Kraepelin test was used as a mental arithmetic task and listening to environmental (natural) sounds as an auditory task. In the verbal study, for an example, we conducted the sensory test twice, once before and once after the task. As a measure of the perceived odor quality in participants after inhalation of a given aroma, we employed a sensory evaluation spectrum. It is a bar graph in which the mean of the difference in score between pre- and post-task inquiry (post minus pre) was plotted against the impression descriptors. Taking into account of the obtained skin temperature changes between pre- and post-task inhalations, the subtle nuances between verbal and non-verbal expressions seen as a function of the two behavioral tasks assigned to the participant suggested that essential oils may have versatile psychophysiological potencies by the nature.