The smell of emotions

Published: 17-10-2020

It is well known that many animals communicate their emotional states by changing their body odor, but the role of the sense of smell in humans has been underestimated for many years. However, research indicates that communication of emotions through smells also occurs in us.

The first research on this subject was carried out by Denise Chen and Jeannette Haviland-Jones in 2000. They collected the smell from under the armpits of 25 young women and 25 young men with gauze pads in two situations: watching a funny movie and watching a scary movie. The second group of study participants was asked to smell the bottles with the scent and indicate which, according to them, contain the scent of a happy person and which of a scared person. It turned out that many study participants were able to sense it.

However, significant differences between the sexes were observed. In the task in which it was recommended to identify which bottle contains the scent of a happy human, men only performed well with women’s scents. Women, on the other hand, guessed the smell of a happy woman as well as a happy man. In the task of pointing out the scent of a scared human being, both women and men coped with this task only in the case of men’s scents.

Further research indicates that even if the smell of an emotion is not consciously recognized, it can affect the emotions of the person who smells it. Groot and his colleagues, similar to the experiment described above, collected the smell of sweat from people watching movie clips. In this case, one movie was frightening and the other disgusting. The second group of study participants performed the task of searching for appropriate signs on the screen, while simultaneously they were introduced with the previously collected smells into their noses. None of the participants in the study guessed the real purpose of the experiment or where the smells came from. Due to the fact that men are characterized by a stronger smell, while women are more sensitive to smells, the researchers decided to include only men in the group of people from whom the smells were collected, while only women in the group of people who smelled. In addition to checking how the participants cope with the task on the screen, the tension in their facial muscles was measured, which gave rise to inferences about their emotions.

The results of the study showed that sniffing the sweat of people who were under the influence of certain emotions can arouse the same emotions. When sniffing the smell collected while watching a horror movie, the facial muscles characteristic of the emotion of fear were activated, while when the smell collected from watching a movie with disgusting scenes was injected, the sniffers flexed the muscles characteristic of the feeling of disgust.

Another study (Prehn-Kristensen et al., 2009) found that the smell of stress can induce compassion. Study participants sniffed the scents collected while waiting for the exam and while playing sports. Brain scans (fMRI) showed that the smell of stress activates the areas of the brain involved in the processing of social and emotional stimuli (fusiform gyrus) and in the regulation of empathy (insular cortex, precuneus, cingulate cortex). Moreover, the activity of areas responsible for attention control (thalamus, dorsomedial prefrontal cortex) and for emotional control (cerebellum, cerebellar vermis) were observed.

References

1. Chen, D., Haviland-Jones, J. (2000). Human olfactory communication of emotion. Perceptual and Motor Skills, 91, 771-781. (pdf at rutgers.edu)
2. Groot, J. i in. (2012). Chemosignals Communicate Human Emotions. Psychological Science, 23(11), 1417-1424. (pdf at researchgate.net)
3. Prehn-Kristensen, A. i in. (2009). Induction of Empathy by the Smell of Anxiety. PLoS ONE 4(6). (text at plos.org)

Source of picture: george Crux, FreeImages.com

Author: Maja Kochanowska