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/ Source: TODAY
By Meghan Holohan

When a deal seems too good to be true or an online dating profile seems like the perfect match, people might say “it smells fishy” to express their doubts.

A recent study finds that this is more than a turn of phrase — fishy smells cause people to feel heightened suspicion.

girl stinks and it closes the nose, unpleasant smell; Shutterstock ID 285591416; PO: today.comShutterstock

“It turns out that a subtle fishy smell elicits suspicion, makes you less likely to cooperate with others, makes you more critical of stuff you read, and you notice more misleading [information],” said Norbert Schwarz, an author of the study and provost professor in the department of psychology and the Marshall School of Business at the University of Southern California.

“You are thinking more critically even about your own thoughts,” he added.

The findings add to what’s known as embodied cognition, the idea that cues from outside the body influence thoughts and feelings.

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Previous research tackled warmth and cold and weighty issues. People holding a warm cup of coffee experience toasty feelings toward others while those grasping a cold cup of joe think others are frigid. People also believe a book is more serious when it actually weighs more.

“There are enough findings across many different domains — physical and social warmth, physical weight and intellectual weight," he said. "Nobody is quite as surprised when these metaphors have an influence but the size of the effect is surprising."

Schwarz and his colleagues conducted two studies to see if fishy smells contribute to distrust.

In the first, they asked 70 students to answer some questions, including a trick question: “How many animals of each kind did Moses take on the Ark?”

The researchers advised the participants to mark any questions that they couldn’t answer or they felt were poorly worded.

About half of the participants, 33, sat in a room that smelled slightly of fish. The remaining 37 answered questions in a room with no smell.

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People in the fishy-smelling room were more likely to point out that the Moses question contained an error.

“The fishy smell acted as a trigger of sorts of feeling of suspicion,” said David Lee, a doctoral student in social psychology at the University of Michigan and another author of the study.

In the second study, 94 students examined a string of numbers — 2, 4, 6 — and had to determine the rule behind their relationship.

On the surface, it seems that each number increases by two, which is not the correct answer.

The 45 students in the fishy smelling room were more likely to second guess themselves and retest their theory; more of the people in the fishy room eventually arrived at the correct rule of “any increasing numbers.”

“Basically, we find when people are close to a fishy smell they are more likely to go against their initial hunch and test out and try out different things,” said Lee. “The fishy smell is allowing people to sort of think differently, go against their initial hypothesis and test out different scenarios.”