Scientists re-examine a famous visual attention experiment to draw new conclusions.
The video begins with this simple question: Count the number of times the players dressed in white change basketballs. If you’ve never seen it, before you continue reading, do the quiz here:
If you pay attention to the movement of the ball, you might not have seen the person dressed as a gorilla sneaking between the players. This 1999 experiment by Harvard University scientists shows that humans have selective attention. When we focus on a specific task, we often ignore the other elements around it. This experiment was so influential in the field of cognitive psychology that it can be found in college textbooks.
New York University psychology researchers have revisited this famous experiment to draw new conclusions recently published in PNAS. The team leveraged thousands of participants on the Amazon Mechanical Turk platform and customized the methodology. First challenge? “Exclude those who have already seen the original experience on YouTube! says Pascal Wallisch, lead author of the study and psychologist specializing in the cognitive neuroscience of visual attention.
The scientists tested different scenarios. Among other things, they changed the speed at which the gorilla crosses the group: sometimes slowly, sometimes quickly. They found that when the gorilla moves quickly, it quickly draws its attention to this unexpected element. Conversely, when moving slowly, as in the original experiment, the brain pays no attention as it focuses on counting the number of passes.
The four NYU researchers didn’t stop there, however. In another part of the experiment, they asked their guinea pigs to count the number of squares that crossed a line in a video. Once again, at a certain moment, an unexpected object (a triangle) appeared on the screen. Has the triangle gone unnoticed? As in the experiment with the gorilla, the speed of movement of the triangle was important.
Asked by Quebec Science about the goals of this experiment, Pascal Wallisch states that he wanted to revisit it after realizing that the speed variation of the unexpected object had not been tested. “In cognitive psychology, there’s this notion of attention, which doesn’t make sense to me, that people aren’t able to perceive a change even if it’s in front of them and they know it’s happening.” The aim of our research was find out if that’s true,” says Pascal Wallisch.
In his opinion, the results are very clear on this point: “The faster the movement, the easier it is to perceive it.” The authors point out that part of the primate brain is responsible for detecting movement. In nature, the rapid movement can come from a predator, a prey or a member of the same species.
“When we think of sight, we often associate it with colors or faces, for example. We don’t necessarily think about movement. Most animals cannot see color. When they see something, it’s the movement that they see. Therefore, a large part of their brain is responsible for the perception of movements, which serve as a detector for life forms,” explains Pascal Wallisch.
In short, our brains would be far more powerful than the 1999 experiment would have led us to believe.
advantages in different areas
Researcher Pascal Wallisch points out that his study could have implications in several areas. For example, illusionists unconsciously use this speed tactic to draw the audience’s attention to one hand and not the other performing a magical manipulation.
In the aviation sector, the dashboard of an aircraft is illuminated from all sides. By moving an element quickly, we could attract pilots’ attention during critical maneuvers.
Following this study, the NYU researcher plans to examine attentional mechanisms in people with ADHD. “It’s just a guess, but people with attention deficit disorder might be more easily distracted by slow movements than people without ADHD,” he surmises.