Human pairs show collective benefit in olfactory perception despite individual differences and verbal limits

Olfaction is a limit case for human communication. Not only does genetic, personal, and cultural diversity make us smell things differently, but perceptual and neurological factors are meant to make it challenging to verbalize our olfactory experiences, besides the affective value that they have for us. Here, we demonstrate that people still achieve a collective benefit in olfactory tasks when allowed to talk to each other, like the benefits only seen in vision and audition. We measured people's individual smell abilities using a standard clinical test and brought them back after 4 weeks in pairs with matching abilities, others with different ones. We asked everyone to perform discrimination and identification olfactory tasks again, but this time, after giving their own answers, they had to discuss and agree on a joint answer. As in vision, pairs matched in abilities performed better than the best of the two individuals. This joint benefit in olfactory performance overturns the long-held belief that smell resists verbal scaffolding.