Say there’s a free concert in the park where you’ve arranged to meet a friend. You arrive and scan the crowd, glimpsing and dismissing a dozen faces every second. Three minutes later you focus on a face…there she is!

The everyday occurrence of facial recognition involves neural tagging, in which the brain sets a unique combination of synapse strengths in a specific cluster of neurons for each distinct face.

At least three regions of the brain are involved in recognizing complicated objects, says SFI External Professor Charles Stevens, a neurobiologist at the Salk Institute. We know that tags for faces are generated in the dentate gyrus of the hippocampus. But how, exactly, the brain generates and uses these tags is unclear. 

In August, Stevens is hosting a working group at SFI to explore this problem. Because visual recognition is so difficult to study, Stevens and colleagues are drawing from the similar and better-known olfactory sensory system to investigate how mammals recognize complex odors and use them to navigate.

Stevens will be joined by Venkatesh Murthy, a biologist at Harvard who studies olfactory-guided navigation in mice, and Massimo Vergassola, a physicist at UC San Diego who has developed a theory for how we navigate with the olfactory system.

During the meeting, the researchers plan to combine experimental data and theory to extend their understanding of the problem for olfaction and set the stage for understanding the problem in other contexts, says Stevens.

More about the August 8-18, 2016 "Olfaction" working group.