Understanding Paradoxical Insomnia
In 2018, Hannah Scott, a sleep researcher at Flinders University, observed a trial participant as she attempted to fall asleep. It took some time—especially since the woman was hooked up to devices tracking her brain activity, eye movements, heart rate, and muscle activation. However, roughly 30 minutes in, Scott noted the unmistakable signs of sleep on the electroencephalogram (EEG): a shift to lower-frequency brainwaves.
The participant entered deep sleep and stayed there for a while. Yet suddenly, she woke up, claiming she needed to use the bathroom. As Scott disconnected her from the equipment, the woman expressed regret, insisting she hadn’t actually fallen asleep yet.
“She was completely convinced she hadn’t slept,” Scott remarked, even though she’d just seen her sleeping.
This situation is referred to as sleep state misperception. Essentially, when awoken, a person may firmly believe they were wide awake the entire time.
According to Matthew Reid, a neuroscientist at Johns Hopkins School of Medicine, this is a common issue for those with insomnia. Insomniacs might feel like they hardly sleep, but studies often reveal they’re actually getting a normal amount of rest. This raises quite the question: how can someone feel so tired if they’re technically sleeping enough but are unaware of it?
This phenomenon, which impacts a notable portion of insomniacs, has been described in various ways, including paradoxical insomnia, subjective insomnia, sleep state misperception, and more recently, subjective-objective sleep discrepancy.
What is Paradoxical Insomnia?
Paradoxical insomnia is a specific type of insomnia. Individuals experiencing it often claim they’re sleeping only a few hours each night and feel unrested. Yet, sleep studies frequently show they are getting more sleep than they perceive—sometimes even a typical amount.
Those struggling with insomnia often face straightforward challenges: difficulty falling asleep, staying asleep, or getting adequate rest. As a result, they might feel fatigued during the day, struggle with concentration, and experience irritability.
Interestingly, total sleep time doesn’t diverge significantly between healthy individuals and those with insomnia. On average, insomniacs sleep merely about 23 minutes less per night than their well-rested counterparts. So if sleep time isn’t the entire story, what else is going on?
Some individuals require more sleep than others, but it turns out that many don’t accurately perceive their own sleep. They might sleep through the night but still feel unrested. This complexity in insomnia is increasingly apparent through various studies.
The term “fausse insomnie,” or false insomnia, first emerged in 1959 when French doctors documented a patient who felt her sleep hours did not align with observed sleep duration. The doctors thought her anxiety about sleep might have skewed her perception. Over the years, sleep specialists have noted that complaints from insomniacs often don’t correspond with the actual sleep they receive.
Although researchers lack a singular measure of how common paradoxical insomnia is—as it goes by various names—it’s not rare, according to Reid. Reports suggest around half of insomnia sufferers sleep less than six hours a night, while the other half get more than that, comparable to those who sleep well.
Who Experiences Paradoxical Insomnia?
Even individuals who usually sleep well might believe they’re awake in the early stages of sleep. However, those with paradoxical insomnia are more inclined to feel they’re awake after two hours. They also tend to report feeling awake during REM sleep, which most healthy sleepers can accurately identify as sleep. In studies involving multiple awakenings, insomnia sufferers often claim they were awake during times they had, in fact, been asleep—more than those who sleep well.
Thomas Andrillon, a cognitive neuroscientist at the Paris Brain Institute, suspects that the awareness of sleep may be more intricate than we’ve assumed. In his research related to memory and learning during sleep, he noticed participants insisting they hadn’t slept even while their brain activity indicated otherwise. He realized this experience wasn’t unique to them; it happened to many—like students falling asleep in class yet unaware they had dozed off.
This is something that many have likely experienced. For example, I often feel I haven’t slept much before an early flight, yet I can remember dreams that contradict that notion. I’ve also flown with a family member who falls asleep effortlessly but complains upon arrival about not having slept.
“You think you’ve been awake all night, but then something reminds you that you’ve actually slept, like someone saying: ‘Oh, you were snoring,’” Reid pointed out.
Why Does Paradoxical Insomnia Occur?
In the past, researchers often believed those with paradoxical insomnia were simply misreporting their experiences. However, brain imaging studies conducted by Andrillon and others suggest that those experiencing discrepancies between their sleep and wakefulness may not be entirely mistaken. Instead, they might be perceiving a unique altered state of consciousness.
Generally, researchers define sleep by the loss of awareness of the environment and specific changes in brain activity. EEG results show identifiable markers like slow waves and sleep spindles.
Yet, conventional methods of observation might overlook the subtleties of brain activity transitioning into sleep or the shifts between different sleep stages. Andrillon noted that when researchers explore deeper brain areas, they often find signs of arousal that could explain the sensation of wakefulness during sleep.
“On a superficial level, it seems like they’re sleeping, but when you dig into the details of brain activity, you can still see signs of wakefulness,” Andrillon explained. This has led some experts to start using the term subjective-objective sleep discrepancy (SOSD) rather than paradoxical insomnia.
In a recent study involving over 800 individuals with insomnia, about 24% exhibited SOSD. Andrillon and his team identified physiological differences between those with SOSD and those without. Individuals with SOSD might not wake frequently, but when they do, their awareness still carries signs of sleep, which could skew their perception of how well they’ve slept.
Are There Solutions for Paradoxical Insomnia?
Cognitive behavioral therapy for insomnia (CBT-I) has shown promise regarding sleep improvement. Interestingly, this method appears to help individuals with SOSD as well. One study found no significant variations in success rates between those with classical insomnia and those with SOSD. Other research confirms that CBT-I can effectively address problems associated with SOSD.
Obsessively worrying about sleeping the right amount may not be beneficial, Scott noted. It’s worth noting that SOSD often correlates with anxious thoughts surrounding sleep. As Andrillon mentioned, individuals with SOSD frequently ruminate on worries about sleep and the day’s events.
Instead, a technique called paradoxical intention, which suggests attempting to not try as hard to sleep, might be beneficial for those affected by paradoxical insomnia.
What’s clear is that the people who aren’t aware of their sleep were previously thought to have faulty judgment. Yet, SOSD serves as a reminder that our understanding of sleep is still evolving. “We’re realizing this is actually quite real,” Andrillon added. “We’ve just overlooked this aspect of sleep.”
