The scent of a lemon may improve a person’s body image, according to a new study led by the University of Sussex in England.
The findings, presented at the 17th International Conference on Human-Computer Interaction (INTERACT 2019), show that study participants felt thinner and lighter when they smelled lemons. In contrast, they felt thicker and heavier when they smelled vanilla.
The researchers believe the results could be used to develop new therapy recommendations for people with body perception disorders or wearable technologies that could improve self-esteem.
“Our brain holds several mental models of one’s own body appearance which are necessary for successful interactions with the environment,” said lead researcher Giada Brianza, a first year PhD student at the university’s Sussex Computer-Human Interaction (SCHI) Lab.
“Our study shows how the sense of smell can influence the image we have in our mind of our body and on the feelings and emotions towards it.
“Being able to positively influence this perception through technology could lead to novel and more effective therapies for people with body perception disorders or the development of interactive clothes and wearable technology that could use scent to enhance people’s self-confidence and recalibrate distorted feelings of body weight.”
The new work builds upon recent research in cognitive neuroscience and human-computer interaction (HCI), which reveals that technology can change people’s body image perception (BIP) by stimulating a range of senses.
Often such research is focused on visual or tactile stimuli and increasingly sound, but this is the first study that looked at how smell can affect BIP.
“Our previous research has shown how sound can be used to alter body perception,” said Dr. Ana Tajadura-Jiménez, from the Universidad Carlos III de Madrid (UC3M).
“For instance, in a series of studies, we showed how changing the pitch of the footstep sounds people produce when walking can make them feel lighter and happier and also change [the] way [they] walk. However, nobody before has looked at whether smells could have a similar effect on body perception.”
The study consisted of two consecutive experiments. In the first one, participants sat at a computer screen while olfactory stimuli were delivered and were then asked to rate the perceived scent using a Visual Analogue Scale — for example, comparing the scent to spiky or rounded shapes, hot or cold, high or low pitch and thin and thick body silhouettes.
In the second experiment, participants stood on a wooden board, wearing headphones, a pair of motion-capture sensors and a shoe-based device which enhanced the pitch of their own footsteps.
Participants were instructed to walk on the spot while olfactory stimuli were released and then asked to adjust the size of a 3-D avatar using a body visualization tool according to their perception of themselves. They also answered a questionnaire about perceived speed, body feelings and emotions.
The results show that the scent of lemon led to participants’ feeling lighter, while the vanilla scent made them feel heavier. These sensations were enhanced when combined with high-pitched sounds and low-pitched sounds of the participants’ footsteps.
“Previous research has shown that lemon is associated with thin silhouettes, spiky shapes and high-pitched sounds while vanilla is associated with thick silhouettes, rounded shapes and low-pitched sounds,” said Marianna Obrist, Professor of Multisensory Experiences and head of the SCHI Lab at the University of Sussex.
“This could help account for the different body image perceptions when exposed to a range of nasal stimuli.”
Source: University of Sussex