Fishy stink heightens critical thinking.

• Position: Misinformation - Brief article

A nose-wrinkling fishy smell does more than tell humans to keep a safe distance: it makes them better thinkers, in a study of metaphor and reasoning, researchers found that people exposed to the slightest whiff of spoiling fish are more likely to detect misleading information.

"If I'm distrustful, then I'm thinking, 'Something's wrong here,' and then I have to think more critically and figure out what is wrong," says Norbert Schwarz, the study's lead author and director of the Center for Mind and Society at the University of Southern California, Los Angeles.

Scientists believe the tendency to respond to fishy smells with suspicion is an evolved mechanism that helped humans survive for millennia. "Something smells fishy" is a widely-accepted metaphor, with variants of it appearing in more than 20 languages worldwide.

In their study, researchers asked 31 students to complete a questionnaire in a booth that smelled slightly fishy because the researchers had, unbeknownst to the students, sprayed it with some fish oil...