Calm down: If you could actually die of moderate sleep
deprivation (SD), PhD students would be an endangered species. So you
can put your fears to rest. Severe SD, however, is an entirely different
matter…
We all know what a missing night of sleep (or two!) feels like: concentration problems, aching joints, short temper. All unpleasant but manageable. SD, both in acute and chronic forms is a common feature of modern life. But several individuals have taken it to the extreme: the longest scientifically-confirmed voluntary period without sleep was 264 hours (11 days), completed by Randy Gardner in 1977 [1]. Towards the end of the study, Mr. Gardner experienced dramatic memory loss, and experienced florid psychosis, on par with other less systematic reports of SD. Beyond this, there is not much that scientists know about the effects of extreme sleep loss in a controlled setting. However, we do know this: if you prevent an animal from sleeping long enough, it will die. The strange thing is, we don’t know why.
The Case of The Sleepless Rats
In the lab, there are several rather nasty experimental paradigms to prevent animals from getting either deep REM sleep, or sleep at all. For example, animals are placed on a small platform in a tank of water. Whenever they start showing signs of relaxing, sometimes visualized by EEG of EMG changes, they are gently handled by experimenters or simply allowed to fall into the water [2].
If you prevent a rat from having any sleep at all, they die within 2-3 weeks [2]. But what if you only block periods of deep, REM sleep? Well, they still die, but manage to hold out just over a month.
What happens to the animals during this time? Rats’ mental states are not so easily queried as humans’, so we can only judge their cognitive health based on (decreasing) performance on behavioral tests [3]. But after a short period, the animals start exhibiting a range of physical and physiological changes, too. Body temperature drops, as does the animals’ weight (despite increased appetite), and they start exhibiting skin lesions. Bacteria flood the intestine, and the immune system becomes overburdened. Then… they die [2,4]. There are several theories about why this happens, for example, that animals have irreversible hypothermia, or severe sepsis. However, rats that are kept warm or given antibiotics still succumb [4].
It’s not entirely clear whether death in this experimental setting is most easily ascribed to severe stress from the environment, total immune failure, brain damage, or some combination of the three [4]. For example, pigeons and mice subjected to the same paradigm have much better physiological outcomes [5], though it seems that the animals in these studies were euthanized before they became as ill as the rats above. Nowadays, researchers seem to be more interested in the subtler effects of SD on things like metabolism and cancer resistance (which are worth a full article [or issue of the newsletter] in their own right) [4, 6].
The Case of the Unlucky Insomniacs
There is one final type of death-by-SD worth considering, though it leaves open just about as many questions as it answers: Fatal Familial Insomnia (FFI) [7]. This is an exceedingly rare disorder which, yes, affects (and kills) humans. 26 families worldwide carry an autosomal dominant gene variant which causes the condition, while only 9 sporadic cases have ever been recorded [9]. This mutation causes changes on PrP, the gene responsible for prion protein and the devastating effects of Creutzfeld-Jakob (aka Mad Cow) disease (CJD). Patients begin exhibiting anxiety and behavioral changes around age 50, which quickly transitions to ever-decreasing periods of sleep and eventually total insomnia. Dementia follows, and patients usually die within a year from complications such as pneumonia [8,9].
Thus, patients with FFI don’t really die of SD per se, rather of generalized brain atrophy accompanied by approximately 6 months without sleep [8,9]. Much like CJD, this disease causes the brain to become riddled with mutant prions and causes atrophy in several areas, notably the frontal cortices and thalamus (the most likely candidate for sleep-related problems) [7,8]. Due to the extremely low number of cases worldwide, there is not a great deal more information, although a mouse model was produced in the late 2000s that recapitulates many features of the human condition [9].
Something to Keep You Up At Night
I’ve been writing for the newsletter for about 4 years now, covering more than a dozen topics. And this article was far and above one of the most grim to research. Real SD is truly the stuff of nightmares (and legally-sanctioned torture [4]). But I digress! The good news here is that most humans are extremely unlikely to die directly by SD. However, there are a host of dangers associated with SD. First and foremost, accidents caused by nodding off or being distracted while doing things like driving. There is also a growing body of evidence linking SD to metabolic problems like obesity and diabetes.
To put it bluntly, SD will catch up with you. It’s just a question of how quickly…
by Constance Holman, PhD Student AG Schmitz
This article originally appeared December 2017 in CNS Volume 10, Issue 04, Sleep
[1] http://bit.ly/1GWPboW
[2] http://bit.ly/1ccEe6e
[3] Alhola and Pola-Kantola, Neuropsychiatr Dis Treat20017
[4] http://slate.me/1WTz4Oe
[5] Newman et al., Physiol Behav 2008
[6] Knutson et al., Sleep Med Rev 2007
[7] http://bit.ly/2z8wwHB
[8] Schenkein and Montagna, MedGenMed 2006
[9] http://bit.ly/2z73PL1
We all know what a missing night of sleep (or two!) feels like: concentration problems, aching joints, short temper. All unpleasant but manageable. SD, both in acute and chronic forms is a common feature of modern life. But several individuals have taken it to the extreme: the longest scientifically-confirmed voluntary period without sleep was 264 hours (11 days), completed by Randy Gardner in 1977 [1]. Towards the end of the study, Mr. Gardner experienced dramatic memory loss, and experienced florid psychosis, on par with other less systematic reports of SD. Beyond this, there is not much that scientists know about the effects of extreme sleep loss in a controlled setting. However, we do know this: if you prevent an animal from sleeping long enough, it will die. The strange thing is, we don’t know why.
The Case of The Sleepless Rats
In the lab, there are several rather nasty experimental paradigms to prevent animals from getting either deep REM sleep, or sleep at all. For example, animals are placed on a small platform in a tank of water. Whenever they start showing signs of relaxing, sometimes visualized by EEG of EMG changes, they are gently handled by experimenters or simply allowed to fall into the water [2].
If you prevent a rat from having any sleep at all, they die within 2-3 weeks [2]. But what if you only block periods of deep, REM sleep? Well, they still die, but manage to hold out just over a month.
What happens to the animals during this time? Rats’ mental states are not so easily queried as humans’, so we can only judge their cognitive health based on (decreasing) performance on behavioral tests [3]. But after a short period, the animals start exhibiting a range of physical and physiological changes, too. Body temperature drops, as does the animals’ weight (despite increased appetite), and they start exhibiting skin lesions. Bacteria flood the intestine, and the immune system becomes overburdened. Then… they die [2,4]. There are several theories about why this happens, for example, that animals have irreversible hypothermia, or severe sepsis. However, rats that are kept warm or given antibiotics still succumb [4].
IF YOU PREVENT A RAT FROM SLEEPING, IT DIES WITHIN 2-3 WEEKS
It’s not entirely clear whether death in this experimental setting is most easily ascribed to severe stress from the environment, total immune failure, brain damage, or some combination of the three [4]. For example, pigeons and mice subjected to the same paradigm have much better physiological outcomes [5], though it seems that the animals in these studies were euthanized before they became as ill as the rats above. Nowadays, researchers seem to be more interested in the subtler effects of SD on things like metabolism and cancer resistance (which are worth a full article [or issue of the newsletter] in their own right) [4, 6].
 |
| Image source: Alyssa L. Miller via flickr |
There is one final type of death-by-SD worth considering, though it leaves open just about as many questions as it answers: Fatal Familial Insomnia (FFI) [7]. This is an exceedingly rare disorder which, yes, affects (and kills) humans. 26 families worldwide carry an autosomal dominant gene variant which causes the condition, while only 9 sporadic cases have ever been recorded [9]. This mutation causes changes on PrP, the gene responsible for prion protein and the devastating effects of Creutzfeld-Jakob (aka Mad Cow) disease (CJD). Patients begin exhibiting anxiety and behavioral changes around age 50, which quickly transitions to ever-decreasing periods of sleep and eventually total insomnia. Dementia follows, and patients usually die within a year from complications such as pneumonia [8,9].
YOU ARE EXTREMELY UNLIKELY TO DIE DIRECTLY BY SLEEP DEPRIVATION
Thus, patients with FFI don’t really die of SD per se, rather of generalized brain atrophy accompanied by approximately 6 months without sleep [8,9]. Much like CJD, this disease causes the brain to become riddled with mutant prions and causes atrophy in several areas, notably the frontal cortices and thalamus (the most likely candidate for sleep-related problems) [7,8]. Due to the extremely low number of cases worldwide, there is not a great deal more information, although a mouse model was produced in the late 2000s that recapitulates many features of the human condition [9].
Something to Keep You Up At Night
I’ve been writing for the newsletter for about 4 years now, covering more than a dozen topics. And this article was far and above one of the most grim to research. Real SD is truly the stuff of nightmares (and legally-sanctioned torture [4]). But I digress! The good news here is that most humans are extremely unlikely to die directly by SD. However, there are a host of dangers associated with SD. First and foremost, accidents caused by nodding off or being distracted while doing things like driving. There is also a growing body of evidence linking SD to metabolic problems like obesity and diabetes.
To put it bluntly, SD will catch up with you. It’s just a question of how quickly…
by Constance Holman, PhD Student AG Schmitz
This article originally appeared December 2017 in CNS Volume 10, Issue 04, Sleep
[1] http://bit.ly/1GWPboW
[2] http://bit.ly/1ccEe6e
[3] Alhola and Pola-Kantola, Neuropsychiatr Dis Treat20017
[4] http://slate.me/1WTz4Oe
[5] Newman et al., Physiol Behav 2008
[6] Knutson et al., Sleep Med Rev 2007
[7] http://bit.ly/2z8wwHB
[8] Schenkein and Montagna, MedGenMed 2006
[9] http://bit.ly/2z73PL1
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