Unexpected Things That Influence Your Dreams

Just try to quash undesired thoughts—about urges, exes, hair loss, deadlines, white bears, whatever—and they're more likely to rebound in your dreams, jack-in the-box-style, found a study at the Goethe University of Frankfurt. (The prefrontal cortex, which usually keeps these things in check, goes offline as you dream.) The researchers tested this by asking volunteers to suppress an unwanted thought for five minutes prior to sleep. Not only was the thought likelier to intrude in their dreams, but suppressing it also led to more nightmares overall. And when you already have a lot on your mind, the one thing you're avoiding is even likelier to rebound. But, as Sigmund Freud pointed out, there's a bright side: "A wish suppressed during the day asserts itself in a dream." That is, the fantasies you deny or otherwise make taboo are also likelier to play out in your sleep.

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