Scent Smarts

Big city life – the sights, the sounds, the smells…is that PIZZA?!?

This is Sandra Tsing Loh with the Loh Down on Science. 

We can smell a warm slice ANYWHERE! But how is it that our nose ALWAYS knows? 

Srinath Nizampatnam and colleagues at the University of Washington in St. Louis SNIFFED out the answer. 

How? Locusts! Even with background smell distractions, these insects are able to reliably smell their gourmet meal of choice – GRASS! The researchers observed the brain activity of locusts while they were exposed to their favorite food.  

What did they learn? Smell recognition involves two groups of neurons. “ON” neurons are activated when an odor is present. Pizza? Think tomatoes, cheese and oregano! 

The “OFF neurons” eliminate competing odors. Like taxi fuel or your coworker’s stinky fish leftovers. Just like locusts, our brains can reliably recognize familiar smells!

Anyway you SLICE it, our brains are doing more than listening to our stomachs! 

Mmmmm, SLICE …with extra pepperoni please! 

Reference: Nizampatnam, S., Zhang, L., Chandak, R., Li, J., & Raman, B. (2022). Invariant odor recognition with ON–OFF neural ensembles. Proceedings of the National Academy of Sciences, 119(2).

Photo credit: Italian pizza photo created by pvproductions (image from