Ever deeply inhaled a fresh, clean scent and felt re-energized? Or lit a candle in the evening to help relax and unwind from the day’s stress? It’s no coincidence— thanks to the olfactory system’s intimate relationship with the brain, certain scents might actually influence our mood.

The Nose Knows— Why It Matters

Photo by Marissa Angell

While sniffing a particular scent can trigger specific moods, it’s hardly automatic. Scents trigger moods because of associative learning— the way our brains tie things together due to past experiences. Before the mind can link an odor to a particular mood, it first needs to associate that odor with an event or experience. The olfactory bulbs, the part of the brain responsible for receiving information about odors, are linked to areas of the brain that deal with emotions and associative learning. This explains why the smell of rubbing alcohol might remind someone of an unpleasant doctor’s visit, or the smell of freshly baked cookies conjures up an image of Grandma.

In one study, subjects who had memories evoked through odor rather than words recalled memories from farther back in time and were more emotionally stimulated by the recollectionsOlfaction and emotion: the case of autobiographical memory. Willander, J, Larsson, M. Memory & Cognitio. 2007 Oct;35(7):1659-63. . But not all scents are created equal: another study suggests that happiness, disgust, and anxiety elicit the strongest olfactory responses, while sadness and anger have the weakest links to odorsBasic emotions elicited by odors and pictures. Croy, I, Ogun, S, Joraschky, P. Emotion. 2011 Jul 25..

Get a Whiff of This — The Answer/Debate

The brain might react to certain scents, but it also seems moods themselves can be influenced by odors. In one study, people who were exposed to natural plant odors were calmer, more alert, and in better moods than those in an odor-free environmentThe impact of natural odors on affective states in humans. Weber, ST, Heuberger, E. Chemical Senses. 2008 Jun;33(5):441-7. Epub 2008 Mar 18.. And research suggests scents such as orange, lavender, coffee, or licorice can give sniffers a longer attention span when presented with informationOdors enhance visual attention to congruent objects. Seo, HS, Roidl, E, Muller, F, et al. Appetite. 2010 Jun;54(3):544-9. Epub 2010 Feb 20. Smell & Taste Clinic, Department of Otorhinolaryngology, University of Dresden Medical School, Dresden, Germany.. The smell of cleaning supplies might even make people more generous, and people in clean-smelling environments could be more likely to engage in charitable behavior.

Expectations about an odor can also influence the mood changes scents bring on, but the verdict is in: to get out of a bad funk, try something citrusy to energize and refresh glum spiritsIrritancy expectancy alters odor perception: evidence from olfactory event-related potential research. Bulsing, PJ, Smeets, MA, Gemeinhardt, C, et al. Utrecht University, Department of Clinical and Health Psychology, Utrecht, The Netherlands. Journal of Neurophysiology. 2010 Nov;104(5):2749-56. Epub 2010 Sep 15.. Down in the dumps? Floral smells tend to promote happiness, while lavender brings on a more relaxing vibeOlfactory influences on mood and autonomic, endocrine, and immune function. Kiecolt-Glaser, JK, Graham, JE, Malarkey, WB, et al. Department of Psychiatry, The Ohio State University, Columbus, Ohio. Psychoneuroendocrinology. 2008 Apr;33(3)328-39.. Or try sniffing lemon or jasmine, which can help stimulate the brainOlfactory influences on mood and autonomic, endocrine, and immune function. Kiecolt-Glaser, JK, Graham, JE, Malarkey, WB, et al. Psychoneuroendocrinology. 2008 Apr;33(3)328-39. Department of Psychiatry, The Ohio State University, Columbus, Ohio..

Certainty Level

Miss Cleo can’t give an accurate fortune, but even she knows smelling something good will bring better days.