Exposure to an unpleasant odour increases the sense of Presence in virtual reality

While olfactory cues affect the everyday human experience in the physical world, few studies have empirically examined the effect they could have on the human experience in virtual reality (VR). This project’s goal was to determine whether the exposure to olfactory stimuli would affect the senses of Presence (primary measure), Reality and Realism (exploratory measures) in VR. In a virtual kitchen devoid of obvious visual cues linking the visual scene to an odour, three groups of 20 randomly assigned participants (12 females and 8 males per group), unaware of the potential exposure to olfactory stimuli, were exposed to either ambient air, a pleasant odour, or an unpleasant odour. The results reveal that the unpleasant odour had a statistically significant effect on the sense of Presence (as measured by repeated brief measures of Presence and the Independent Television Commission Sense of Presence Inventory), but the pleasant one did not. The lower perceived intensity of the pleasant odour may have contributed to its lower detection rate which, in turn, may have contributed to the pleasant odour’s lack of effect on the sense of Presence. Neither of the olfactory stimuli had an effect on either the sense of Reality or the sense of Realism.