Scent is sometimes described as emotional, but its influence is physiological too. Unlike the other senses, smell has direct access to the centres of the brain involved in memory, mood and regulation. This is why our mood can sometimes shift in response to a scent before we have consciously registered it. Understanding this process allows us to use scent more intentionally.
When you inhale, aromatic molecules travel to the olfactory receptors. These receptors send signals to the olfactory bulb, which has close connections with the Limbic system. The Limbic system is associated with emotion, memory and aspects of nervous system regulation, and is linked to instinctive responses.
Other senses are processed through the thalamus first and are therefore often interpreted more analytically. The more direct pathway between scent and the Limbic system is what makes olfaction distinct.
Because of this close link to memory and emotion, scent can evoke associations and nervous system responses quickly, often before a conscious thought has formed. In this way, scent can be used subtly to support a steadier or more settled response.