Who did the study: Northwestern University researchers, published in the journal Science
What they found: People’s sense of smell sharpens when something bad happens.
How they did it: Twelve volunteers were given electric shocks while they smelled unfamiliar lab chemicals. The volunteers were far more likely to correctly identify those odors during later smell tests after receiving the electric shocks than they had been able to do before the shocks.
Why that happened: MRI scans showed that there were changes in how the brain’s main olfactory region stored the odor information, essentially better imprinting the shock-linked scent so it could be distinguished more quickly from a similar odor.
What that means: The sensitivity to smells we associate with danger almost certainly is a survival trait evolved to help humans rapidly and subconsciously pick a dangerous odor from the sea of scents constantly surrounding us.
Why it matters: It could be a clue for why some people have anxiety disorders. If someone’s olfactory region does not distinguish a dangerous odor signal from a similar one, the brain’s emotional fight-or-flight region can overreact. [ AP ]
