Psychophysiological Effects of Aroma Inhalation during a Short-term Cognitive Stressor: A Preliminary Study using Eight Different Aromas

Abstract

We investigated the psychophysiological effects of eight different aromas under a short-term stressor, in a within-subject experiment using an olfactometer. In this preliminary study, 6 male university students performed a 30-min calculation task under the aroma conditions: Chocolate, Strawberry, Green tea, Apple, Citrus ginger, Chamomile, Cedarwood, Musk or dipropylene glycol (control). Each aroma was intermittently delivered using a proprietary olfactometer on separate experiment days. Along with a visual analogue scale for psychological assessment, skin conductance level and electrocardiograms were recorded throughout the experiment. The increase/decrease in heart rate and high-frequency component of heart rate variability during the task were inhibited by Cedarwood, Strawberry, Green tea, Apple, and Citrus ginger, demonstrating inhibitory effects on cardiac sympathetic nervous system elevation and parasympathetic nervous system suppression. While identifying some prominent aromas for further research, the study revealed a stimulus-specific nature of aroma which led to discrepant psychophysiological effects.