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Watch a bacterium chase down the source of an enticing molecular trail using chemo-taxis, and it’s clear that its sensory and navigation abilities are tightly linked. But could the same be true for humans?
In 2014, Louisa Dahmani, then a graduate student at McGill University in Montreal, set out to answer that question. After having reviewed the literature on studies of spatial memory and olfaction in people, “I realized that the two functions seemed to rely on similar brain regions,” she explains. “But no one had actually looked at it directly and tested the same sample of participants on an olfaction and on a spatial memory task.”
Dahmani, her advisor Véronique Bohbot, and their colleagues set out to rectify that. The group recruited 60 volunteers and tested their ability to identify 40 odors, from menthol to cucumber to lavender. The researchers also had the subjects do ...