Anyone who has ever put off their lunch break just a little too long knows how much hunger can mess with your head. But hunger doesn't just change how we think. It can fundamentally alter how we perceive the world.
That's the finding of psychologist Rémi Radel of France's University of Nice Sophia-Antipolis. He designed an experiment in which 42 students were told to show up at noon after at least three or four hours of not eating. They were then told either to come back in ten minutes - leaving them no time to grab food - or an hour, which would provide enough time for lunch. The participants then looked at a computer screen as eighty words flashed by, each appearing on the screen in tiny font for just 1/300 of a second.
Considering the size and time constraints of the words, the students should not have been able to consciously perceive which word they were seeing. But after each word, they were given two similar choices and asked to pick which one they had seen, as well as say how bright the word looked. When presented with options like "gateau" and "bateau" - the French words for cake and boat respectively - the students who hadn't had lunch would generally choose the food-related and report the food words were brighter than their counterparts.
That might not sound so impressive - sure, hungry people would be more likely to see food-related words everywhere. But the key here is that they were actually better at accurately picking up on food words - which accounted for about a quarter of the words shown - than the participants who had eaten. It wasn't so much that the hungry students were seeing what they wanted to see, though that probably was at least a part of it.
The more intriguing possibility here is actually that the hungry students' senses were primed to pick out words their brains associated with hunger, and the fact that this happened in a time frame far too short for the brains to consciously pick out the food-related words suggests this is actually a sort of instinctual process. And it's not as though they were looking at photos of a cake, suggesting this is a fairly sophisticated recognition process, as Radel himself argues:
"This is something great to me, that humans can really perceive what they need or what they strive for, to know that our brain can really be at the disposal of our motives and needs. There is something inside us that selects information in the world to make life easier."
Via Psychological Science. Image by dichohecho on Flickr.