For some people a fever is enough. Somewhere in the region of 39C I start having what I can best describe "emotional hallucinations" or "hallucinations of the mind's eye." There is nothing sensory (auditory, visual, physical) in the classical sense, but I know that something is there and it is terrifying (even though I have always been aware that it's a hallucination).
I had an unknown parasite, distantly related to Malaria, for two weeks as a child. This was just enough to push me into delirium. I "hallucinated" a black hole in my room, not one the size of my room, but real stellar proportions and gravity. I also hallucinated a radio chasing me around. I never saw, heard or felt either of them, I just knew that they were there, and were not there.
I've had wildly vivid dreams ever since. They are blandly authentic. Some of them would probably make great movies. Every night I hope I have one of those dreams, but they are becoming less and less frequent.
>Delirium in intensive care units is extremely common
The first time after 48 hours the auditory hallucinations started, but I thought it was music traveling through the HVAC from the wing of the hospital that was being remodeled so I said nothing of it. The second time after 48 hours the auditory hallucinations came again and the nurses had uncomfortable looks on their faces when I explained it to them. Basically it was constant hip-hop, metal, or psychedelic music, droning constantly.
>extremely stressful situations, abnormal biochemistry, and powerful pharmaceuticals.
The constant clicks and beeps of the IV machine, the little lights that never turn off, and all the other interruptions of a hospital stay make for a very stressful situation. The last time that I was in the hospital for it a couple years ago (and surely hope it is the last time, for my daughter's sake) they had implemented alarms on the beds for those under heavy pain medications that went off anytime you attempted to get out of bed, leading to the feeling of being imprisoned.
By the end of each time that I was in the hospital it was constant auditory and intermittent visual hallucinations, and it was horrible. Typing all of this has brought all the vividness back (and the feelings of being trapped in a nonsensical world), which makes me think maybe I as well should write about my experiences.
There is obviously more risk to unexpected hallucination, but always some risk if it happens. I still think it's a really interesting risk minimisation proposition.
> Only now I can wake up any time I want.
The author talks about dreams, but dreams are just one aspect of the ICU mental experience. The line between dreams, hallucinations, and memories can collapse.
Delirium in intensive care units is extremely common, affecting up to 80% of some patient populations. It is the result of a combination of highly vulnerable patients, extremely stressful situations, abnormal biochemistry, and powerful pharmaceuticals. It is poorly understood.
This delirium can pose danger to staff and patient in hospital, and can have lasting cognitive impact on patients once they leave. PTSD-like symptoms are not uncommon and are certainly under-treated. Given how common delirium in ICUs is, most facilities have limited or no psychiatric staffing for ICU mental health support.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2391269/
I spent three days in a coma as a result of hepatic encephalopathy, among other episodes related to end stage liver disease. Some day I'll write more about the experience. Incredibly vivid dreams are just one piece of it.