Neuroscience: Daydreams can make you smart or sick

Daydreaming often has a negative reputation. But in everyday life, some situations are so tiring that our minds can wander. For example, a long train ride through a barren landscape. Or an endless team meeting at work. Or a less-than-compulsive speech at a celebration with no end in sight.

But there's no need to feel guilty. Daydreaming can actually be beneficial, as scientists at the Max Planck Institute for Human Cognitive and Brain Sciences in Leipzig and the University of York in England discovered. Certain brain structures responsible for cognitive control actually work together more effectively when we indulge our thoughts—but only if we do so intentionally.

Those who can control their daydreams benefit from it, the scientists emphasize. This means suppressing them when it's important and allowing them to run free when possible. They can actually increase a person's concentration and performance because they're like a short vacation for the brain. Brain waves switch from beta waves (you're focused and mentally active) to theta waves (you're deeply relaxed). Psychology also knows that letting go creates space for creativity.

Despite all the relaxation that letting your mind wander brings, daydreaming can also have disadvantages. For example, if you invest too much time in daydreaming every day, this is called maladaptive daydreaming. It refers to a person losing themselves in their daydreams and forgetting or neglecting everyday life. However, those who permanently withdraw into their fantasies risk depressive moods. Furthermore, those affected can find it stressful if such phases last too long.