Sleep Paralysis

Usually when people experience sleep paralysis, they usually feel an evil presence in the room. Some will hear voices, some will feel the pressure of demons sitting on them, and others will actually hallucinate shadows in their rooms. Sleep paralysis is also linked to most cases of alien abductions and encounters.

I hear this happens more frequently in mental hospitals, both because you're REALLY hearing voices and seeing things, and because the other lunatics are what you're hearing and seeing.

Srs add-on: I've never had this happen to me. Sounds weird.