Most animals close their eyes when they sleep. But did you know some amazing creatures can actually sleep with their eyes open? It might seem strange, but these animals have developed abilities to ...

A recent study observed sleeping participants' pupils during sleep, using a new method that could have implications for studying sleep disorders. reading time 2 minutes Though sleep is a time to power ...

Have you heard the saying about “sleeping with one eye open”? It’s a bit of metaphoric advice about staying vigilant—and a way to describe very light restless sleep. But sleeping with eyes open is ...

Q. How do sleep disorder centers evaluate patients? A. Among the tests used by accredited sleep disorder centers is overnight nocturnal polysomnography. This test consists of videotaping and ...