Why do I feel sleepy until the moment I get in bed?

Lying in bed unable to fall asleep is often called conditioned or lured arousal, says new research out of the University of Pennsylvania. It's one of the most common sleep problems, and experts think it happens because something in your sleep environment has told your brain that getting in bed should “arouse” you or wake you up, instead of put you to sleep.

There are plenty of obvious things that can trigger tossing and turning, and thinking about work right before you try to wind down is one. Using a laptop in bed, which creates the idea of the bed as a place for work or entertainment, is another.

But even those with normally good sleep habits can get thrown into this kind of sleep cycle after a stressful event—a job loss, say, or the death of a loved one, according to IHPI member Ronald Chervin, director of the U-M Sleep Disorders Center. Worrying disrupts your sleep, and that pattern can cause your brain to associate your bed with wakefulness in the same way it would if you were using a laptop.

It's sometimes called " psychophysiological insomnia " and once it starts, the cycle of sleeplessness tends to perpetuate itself.

The most effective way to treat it, say sleep experts, is through cognitive behavioral therapy for insomnia, or CBT-I. This typically involves regular visits to a clinician and is aimed at changing your sleep schedule and habits. “A key part of what we teach people is to keep the bed for sleeping,” says Chervin.