Our sense of smell is strongest at night. So if you feel like your pets seem extra smelly, or your bubble bath is a bit too fragrant in the evening hours, you’re not just imagining things. You’re picking up on scents that are somewhat dampened during the day.
Why is smell important?
Smell influences everything from taste perception to memory formation. However, what you may not know is that our ability to detect and discern scents fluctuates throughout the day, peaking during the late hours. This might seem trivial or even surprising, but it is a fascinating aspect of our biology. And it’s linked to our circadian rhythms.
The circadian rhythm is an internal process that regulates our sleep-wake cycle. It repeats roughly every 24 hours and impacts many physiological processes, including hormone release, body temperature, and various neural functions. Interestingly, this includes our olfactory sensitivity – our ability to perceive smells.
During the daytime, our brains process a multitude of sensory inputs. The sights, sounds, and tactile sensations we encounter are processed and analyzed, taking up significant neural resources. Consequently, our sensitivity to smells is somewhat overshadowed by this barrage of information.
Why is our sense of smell strongest at night?
However, the scenario changes at night. As the environmental stimuli decrease and our focus shifts inward, our sensitivity to smells becomes more pronounced. This shift is likely due to changes in body temperature and brain activity that occur during our sleep-wake transition.
The nocturnal enhancement of olfaction has implications beyond being a mere biological curiosity. For one, it directly influences our sleep quality. We are more susceptible to disturbances from unpleasant or potent odors at night. Therefore, the significance of maintaining a fresh and pleasant sleeping environment becomes clear for a good night’s sleep.
Moreover, this increased olfactory sensitivity might have roots in our evolutionary history. Our ancestors needed to be alert to dangers like predators or fires, especially during the night. A heightened sense of smell would have been advantageous in such scenarios, leading to better survival and reproductive success.
On a practical level, this knowledge can be advantageous to various industries, especially those involved in perfume and scent manufacturing. By understanding our olfactory system’s functioning, businesses can tailor their products for maximum impact during the evening hours.
Source: “How Smell Affects Your Sleep” — The Sleep Foundation