My brother in-law died many years ago now My sister related an incident that took place in the hospital when he was in palliative care. She described it as very disturbing, bordering on frightening, not quite terrifying. Her husband described strange looking beings on the ceiling looking down at them. Now before you tell me it was the drugs he was on giving him hallucinations, he was virtually drug free, only on very mild pain killers, he had an extremely high pain threshold (BTW, had stomach cancer) She told me that everytime they "appeared" about 30 seconds before her husband would tell her they were back, the room would become alot colder to the extent she would look up to the ceiling whenever it cooled and could make out dark shapes in the corners of the room.