Turns Out the Nose Really *Does* Know: How Smell Unlocks Memory and Identity | WUNC

It was in the first few months of the COVID-19 pandemic that scientists discovered an early and telltale sign of infection: loss of smell, or anosmia.

The uptick of anosmia threw into relief the many ways that smell affects day-to-day life, from smelling gas leaking from an unlit burner to being able to fully enjoy food. The olfactory system is also linked to the parts of the brain that govern emotion and memory, which leads smell to affect even our moods and relationships.

Host Anita Rao talks with Dr. Rachel Herz, a neuroscientist and psychologist, about how smell works and how it affects our relationships and memories. Rachel is the author of “The Scent of Desire” and “Why You Eat What You Eat.” Rao also talks with Bonnie Blodgett, who lost her sense of smell in 2005 and discovered how much it changed in her life.

Also joining the conversation is Christina Degreaffenreidt, the founder and creator behind Multifaceted, a candle-making company in Greensboro, North Carolina.

Thanks to Sandra Davidson, Jaime Gonzalez, Amanda Magnus, Ashley Phillips and Erika for their contributions to this episode.

The Nose By the Numbers

400
the number of olfactory receptors humans have to detect odors

Specific receptors detect the unique molecular composition of smells like coffee brewing or food rotting, which draws the brain’s attention to the source of the scent.

1 trillion
the number of scents the human nose can distinguish

If the molecular components of two scents overlap by over 50%, the nose has trouble distinguishing them. But there are billions of scents that do not overlap that the nose can pick out.

0
the number of times the odor you give off is the same as the odor given off by another person.

The way you smell is unique to you – just like your fingerprint.

(Sources)