Scientists Have Discovered How Our Brains Know When We Need to Pay Attention

alert woman driving car
alert woman driving car

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We've all experienced the feeling that comes with sitting at a stoplight waiting for it to turn green or standing in line at a coffee shop waiting for our drink to be prepared. We generally know about how long each of these situations should take and therefore, we can judge whether we have time to change the radio station, make a quick phone call, use the bathroom, or do another speedy task. This judgment is based on our brains' ability to know when we need to pay attention. A team of scientists recently conducted a study aimed to understand how our brains when—and whether or not—to pay attention.

"Our experiment taps into the basic ways we use probability in everyday life, for example when driving our car," said Matthias Grabenhorst of the Max Planck Institute for Empirical Aesthetics (MIPEA). "When approaching a railroad crossing, the probability of the gates closing determines our overall readiness to hit the brakes. This is intuitive and known."

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To understand how different sources of uncertainty affect human anticipatory behavior, researchers used a simple experiment in which they systematically manipulated the probabilities of whether—and—when sensory events will occur and analyzed human reaction time. Their findings were published in the Proceedings of the National Academy of Sciences.

"We found, however, that this readiness to respond drastically increases over time. You become much more alert, although the probability of the gates closing objectively does not change," said Georgios Michalareas of MPIEA. This effect of whether an event will occur is different than knowing when it will happen. The brain knows when to pay attention and can distinguish between these two probabilities.