We all know of the supposed intelligence benefits of including fish in our diet. It's why we start necking cod liver oil around exam season and the justification we gave ourselves for devouring that hefty portion of fish and chips last weekend (it's good for your brain, duh.)
Despite its omega-3 and lean protein-packed goodness, fish doesn't have the most appealing smell in the world. (Insert pun about "something fishy" here.)
However, a study published this week in the Journal of Experimental Social Psychology has found that alongside the benefits of eating fish, the smell alone could improve our reasoning skills.
While it's been proven that the nose acts as an early warning system against questionable-smelling food (and people, for that matter), the new research shows that it may also be able to alert us to suspicious ideas and concepts.
Carried out by researchers at the University of Michigan and the University of Southern California (USC), the study saw 61 students tackle two questions: the first a factual one, and the second—"How many animals of each kind did Moses take on the Ark?"—a trick one, known to produce the incorrect answer of two. (Those who paid attention at Sunday School will know that it was actually Noah, not Moses, who took animals on the Ark.)
Under normal conditions, over 80 percent of the students fell for the trick question but the 31 students who had been exposed to the smell of fish oil performed much better. Over 40 percent of these participants suspected that there was something fishy going on (sorry) and chose the "Can't Say" button, rather than answering incorrectly. These participants did not identify the first factual question as unanswerable, showing that it wasn't a mistrust in general that impacted their second answer, but an improvement in reasoning.
In the second experiment, participants were given the Wason selection task, a problem-solving challenge to find the rule underlying a series of numbers. Those not exposed to the fish oil smell displayed an error known as the "confirmation bias," meaning that they stuck to a previous, incorrrect hypothesis, with only 28 percent attempting to disprove their workings.
In contrast, almost half of the participants exposed to the fish oil smell wafting from a strategically placed dustbin underneath the table critically tested their answers, leading to better success rates at the problem as a whole.
Norbert Schwarz, psychology and marketing professor at USC and one of the study's authors explained to USC News why fish stink may trigger better critical thinking: "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."
It seems that the suspicion triggered by smelly foods may also extend to the social sphere and even academic reasoning, heightening our powers of scepticism.
It's like they always say: the nose knows.