Question: I sometimes have this strange sensation before I awaken -- I can open my eyes, but I can't move. Is this a sign of a sleep disorder?
Answer: This is a phenomenon referred to as sleep paralysis. This is characterized by upon awakening, what happens is, you're awake, but you feel like you are paralyzed and cannot move. Needless to say this can be quite frightening to the person who's experiencing this but the key to remember, is that this is typically a benign issue and you should just remain relaxed and be reassured in the fact that you will ultimately awaken.
If this sleep paralysis occurs in the context of daytime sleepiness, or with intense emotion, there is loss of muscle tone that occurs or if upon drifting to sleep, you're hearing or seeing things that are not there; the sleep paralysis may be an indicator of a sleep disorder called narcolepsy.