I had a distant uncle who said that he suffered from chronic insomnia. When I asked him once what he did all night, he said that he just lay in bed and let his thoughts wander and dozed off from time to time for very short periods. But this did not seem to cause him to be irritable or absent-minded or show any of the symptoms that the rest of us may display on those occasions when we have not slept well. He was as fully functional as anyone else.

Martin J. Clemens says that he suffers from chronic insomnia and needs sedatives to get any sleep at all. He says that his personal record is 90 hours without sleep. In general, total insomnia is fatal and such people who have what is known as Fatal Familial Insomnia (FFI) usually survive less than a year and there is no cure or remedy.

As Clemens describes it:

FFI is a neurological condition caused by a misfolded protein in the DNA of the afflicted, of which there have been only about 100 cases. That protein, called a prion protein, is known as PrP^Sc (PrP^C in non-FFI subjects). Essentially, the prion form of the protein causes a change in certain amino acids – due to the protein strand folding incorrectly – which, when combined with other genetic markers, then affects the brain’s sleep centers. FFI is genetic, and therefore hereditary, but there is an even rarer form known as Sporadic Fatal Insomnia (sFI) that occurs spontaneously, the cause of which is not understood. You may wish to know that PrP^Sc is the same protein that’s responsible for bovine spongiform encephalopathy, also known as Mad Cow Disease.

But some people claim to have not slept in years, with one woman claiming not to have done so for 30 years and a man said that he had not slept for 41 years, both without dying or seemingly suffering from the many symptoms associated with sleep deprivation. How could this be?

Clemens says that there is another disorder called Sleep State Misperception (SSM) that “describes people who mistakenly perceive periods of sleep as wakefulness. Basically, they really do sleep, but they just don’t realise they did… The key to SSM is that those who suffer with it will earnestly claim that they haven’t slept, or have slept very little, but during sleep studies, they show normal sleep pattern.”

So now I am wondering about my distant relative. As far as I know, he never tried to get treated for his condition or test to see how much he was actually sleeping. Since he seemed to be able to function normally, maybe he slept more than he realized.