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What Happens in the Brain When You’re Dreaming

A mesmerizing dive into the latest science

Photo: Jose A. Bernat Bacete/Getty Images

TThe brain does something special during sleep. Instead of simply switching off, it activates patterns of activity that can lead to dreaming. But what exactly is happening to the brain during a dream? It’s a question that has puzzled scientists for a long time, and new research is revealing some answers.