Scents

Arshamian lead a team that identified scents perceived as pleasant by cultures worldwide.  They report that they asked people “from 9 diverse nonwestern cultures—hunter-gatherer to urban dwelling—to rank . . . odorants from most to least pleasant. . . . there was substantial global consistency. . . . Taken together, this shows human olfactory perception is strongly constrained by universal principles. . .

Michels and colleagues evaluated how scents influenced eating after people were stressed.  They share that “Before and after Trier Social Stress Test, 91 participants . . . inhaled one odor during 10 min: Scots pine, grass . . . or control (i.e., demineralized water). . . . Both nature olfactory exposures improved some stress outcomes. Both were associated with lower cortisol in non-stress conditions, but only grass odor was more beneficial for negative affect [mood] decrease after stress. No effect on heart rate variability was seen. . . .

Cowan and co-workers increase our understanding of virtual experiences.  They “employ four studies using a variety of both ambient (i.e., actual scents) and imagined (i.e., prompted through description) olfactory cues in field (i.e., Facebook A/B testing), online, and laboratory settings. Our findings show . . . that in retail-centric VR environments, the presence (vs. absence) of olfactory cues heightens immersion. In turn, immersion elicits flow, which improves brand responses.”

Liu and colleagues evaluated the implications of scenting office spaces.  They studied the “effects of ambient bergamot scent on the stress levels of office workers by exposing them to the scent while stressors persisted as the workers continued to work on the office tasks. . . . The change in heart rate variability revealed that bergamot scent increased stress among males but not for females. The reported pleasantness and comfort followed the same trend.

Woo and colleagues studied the cognitive implications of nighttime scenting; it is possible that their findings are useful in other contexts.  The investigators report that “Male and female older adults . . . age 60–85, were enrolled in the study and randomly assigned to an Olfactory Enriched or Control group. Individuals in the enriched group were exposed to 7 different odorants a week, one per night, for 2 h, using an odorant diffuser. Individuals in the control group had the same experience with de minimis amounts of odorant.

Ruzeviciute and colleagues investigated whether scenting an object influences how far people feel they are from it.  The investigators learned, using a number of different scents, objects, and distances, that scented objects seem closer than those that aren’t:  the “effect emerges even when scents emanate from targets that are typically unscented (e.g., notepad. . .), it is attenuated [reduced] when the scent is not associated with the target. . . . presence of an object's scent biased participants by making them underestimate the actual distance to the object.

Chae, Yoon, Baskin and Zhu studied how what we smell influences what we eat.  They determined that “the effects of indulgent food scents [the smell of chocolate chip cookies baking, for example] on preference for indulgent food items, which Biswas and Szocs (2019) identify in joint decision tasks, hold when foods are evaluated separately. . . . Based on counteractive-control theory, we propose that extended exposure to an indulgent olfactory cue influences motivation by activating one’s diet goal, resulting in reduced intended indulgent food consumption.