Decomposition of an odorant in olfactory perception and neural representation.

Molecules-the elementary units of substances-are commonly considered the units of processing in olfactory perception, giving rise to undifferentiated odour objects invariant to environmental variations. By selectively perturbing the processing of chemical substructures with adaptation ('the psychologist's microelectrode') in a series of psychophysical and neuroimaging experiments (458 participants), we show that two perceptually distinct odorants sharing part of their structural features become significantly less discernible following adaptation to a third odorant containing their non-shared structural features, in manners independent of olfactory intensity, valence, quality or general olfactory adaptation. The effect is accompanied by reorganizations of ensemble activity patterns in the posterior piriform cortex that parallel subjective odour quality changes, in addition to substructure-based neural adaptations in the anterior piriform cortex and amygdala. Central representations of odour quality and the perceptual outcome thus embed submolecular structural information and are malleable by recent olfactory encounters.

Why do people gossip? Reputation promotes honest reputational information sharing.

Gossip, sharing information about an absent person, is an important way of spreading reputational information, crucial in fostering human cooperation. However, why should information possessors engage in gossip, and why should they be honest? We addressed this question based on a reputational account. In study 1, we found that when observed by potential investors, people were willing to pay more to share reputational information with those in need. Moreover, engaging in gossip did confer reputational benefits for gossipers by receiving more trust from investors, and gossipers' willingness to gossip predicted their subsequent trustworthiness. Study 2 further verified that observability promoted only honest information sharing and deterred dishonest gossiping. Consistently, only honest gossipers were trusted more, while dishonest gossipers were perceived to be even less trustworthy than non-gossipers, and only the motivation for honest gossiping could reflect gossipers' trustworthiness. These findings suggest that reputation can provide a solution to encourage gossiping and secure honesty.