When we are focusing on one task, we often fail to notice something obvious in our field of view. This phenomenon, known as inattentional blindness, was famously demonstrated in a study involving a person in a gorilla suit, which participants failed to spot. But now it seems the gorilla isn’t so invisible, and we do actually take in information even when we might miss the wider picture.
, and then at Harvard University, made a short video featuring people passing basketballs. Halfway through the video, someone in a gorilla suit walks through the shot. When volunteers were asked to count the number of passes made by people in white t-shirts, only half reported seeing the gorilla.
“I showed my daughters the famous gorilla demonstration, and one of them couldn’t believe that there had been a gorilla there, and I remember that experience myself,” says at Johns Hopkins University in Baltimore, Maryland.
Advertisement
But the results of some other studies made him think that simply asking people if they saw something unexpected might not reveal the full picture. To test this, Phillips and his colleagues got 25,000 people to do one of five experiments online for a small fee.
In the first experiment, for instance, people were asked to look out for crosses appearing on a screen for 0.2 seconds and say whether the horizontal or vertical arms of the cross were longer. On the fourth occasion, a red line appeared on one side of the screen as well as the cross.
When volunteers were asked, “Did you notice anything unusual on the last trial that wasn’t there on previous trials?”, 71 per cent said yes.
But when they were told that a red line appeared on one side of the screen and were asked which side it was on, 87 per cent chose the correct side. Of those who replied no to the first question, 64 per cent chose the correct side, far more than the 50 per cent that would be expected by chance. The results of the other four experiments were similar.
“I think it shows clearly that people might well have processed some information about the critical unexpected object even when they reported not having seen it,” says Simons, who is now at the University of Illinois Urbana-Champaign and wasn’t involved in the new study. “We should be wary of attributing that to anything subliminal or subconscious, though.”
Phillips thinks the simplest explanation for his findings is that some people were partly aware of the unexpected object, but they were reluctant to say they had seen it when they weren’t certain.
“So, that’s a bias in relation to saying whether they saw something or not,” he says. “And the point about it being a bias is that it’s something you can work with. You could potentially try and train people in fields where it is really important they don’t miss things.”
Phillips says the study is in no way debunking the notion of inattentional blindness. “It shows that there really is something very striking going on when attention is consumed by another task,” he says. It’s just that people may not be as completely unaware as previously assumed.
bioRxiv
