In certain circles, it's called the "death sleep." The person just curls up in bed and conks out. No tossing, no turning, no trouble. Instead, they close their eyes and slip into the sort of meaty, restorative shuteye so many of us crave — a sleep so deep it's death-like.
Being able to lie down and fall asleep without delay or difficulty sounds wonderful, right? Certainly. Well, a particular group of people seems to enjoy this brand of sleep on a nightly basis: psychopaths. That is, the one-or-so percent of the population who are pathologically indifferent to the welfare of others. Psychopaths may be relatively rare, but they pop up frequently in the criminal justice landscape. Upwards of 15 percent of violent offenders bear psychopathic traits. And making headway in sleep science hinges on figuring out why rest goes wrong as well as right — even when it goes right for people who do a lot of wrong.
"Psychopaths are great sleepers," said Kent Kiehl, a neuroscientist and researcher who's written dozens of papers on psychopathy and currently teaches at the University of New Mexico. "They are typically low-anxious individuals who do not have any sleep-related problems, in prison or out."
Let's set the record straight: Deep sleepers shouldn't assume they're devoid of empathy. The science of psychopath sleep is thin. In fact, it barely exists. But, it's also a case where jiggly entrails of research start to come together when we pay attention to stories from unvetted strangers. Taken together, formal studies and stray web communities make the case that psychopaths sleep with machine-like ease and speed.
It's not a far-off thought. Some mental "conditions" — encompassing both disorders and atypical psychological or cognitive dispositions — affect sleep in unexpected ways. But the anecdotal and scientific evidence suggests that psychopaths sleep exactly as we might expect: unburdened by guilt, worry and other pesky feelings that keep empaths up (and get them down). And in a country where most people list rest among their demons, a conflict-free relationship with bedtime is something to behold.
In everyday parlance, sociopathy, psychopathy and Antisocial Personality Disorder (ASPD) are used interchangeably. From a clinical perspective, however, the terms carry different meanings, although experts may dissagree on what those differences are.
"Sociopathy," for example, suggests that social forces (e.g., poverty, family dynamic) lie at the root of the squishy personality disorder. The clinical label ASPD (Antisocial Personality Disorder), by Kiehl's account, is "a very limited construct that only partially assesses the complete personality profile." Finally, "psychopathy," Kiehl said, "is used in modern academic settings; assessed using the Hare Psychopathy Checklist-Revised, which captures all 20 traits associated with psychopathic personality." (Kiehl was "co-mentored" by Robert Hare, the Canadian psychologist who developed the Psychopathy Checklist in the 1970s. Clinicians still use a revised version of the checklist to assess psychopathy today.)
In a 2010 paper on sleep problems in prisoners with personality disorders, psychologists articulated a similar relationship between ASPD and psychopathy: "Psychopathy is a more serious personality disorder than ASPD, characterized by pervasive antisocial behavior, as well as marked dysfunction in emotional connectedness to others. (Antisocial Personality Disorder requires just the former, not the latter.)"
For simplicity's sake, let's use "psychopath" as a catch-all term.
Studies on "death sleep"
The notion that psychopaths might have signature sleep patterns dates back to 1970. Hare, the pioneering psychopathy researcher, proposed that people with chronic antisocial tendencies have decreased REM sleep.
The argument, laid out by psychologist Nathan Michael in a 2001 paper, may seem a little roundabout. Depression is associated with higher-than-average REM sleep. People with depression are characteristically inhibited — unlike psychopaths, who tend to do and say what they want. Basically, the logic is: When it comes to psychopathy, assume the opposite of whatever's going on with depression.
Additional support for this theory comes from rat studies conducted in the late '70s that depicted REM-deprived rodents as fearless in the face of frightening stimuli. In humans, psychopathy is associated with abnormally little fear of criminal culpability. And research has shown that people with psychopathic traits have weak startle responses, meaning they aren't easily rattled by surprises. Taken together, Michael reasoned, "evidence suggests that REM sleep may serve as a protective factor against antisociality, thus reinforcing the notion that sleep pathology in the form of decreased REM sleep may be related to some forms of recidivistic antisocial conduct."
But, as of 2001, sleep scientists hadn't done much to support or refute Hare's idea. In a lone 1980 study, EEG analysis unearthed no evidence of abnormal sleep in psychopathic inmates. To the contrary, wrote researchers, "psychopaths with abnormal EEGs tended to have the highest REM time and percentage of the inmates."
For the next 23 years, the science of sleeping-sans-empathy remained stagnant. Then, psychologists from Finland more or less picked up the torch. In 2003, the team ran its first of two studies on people with ASPD (rather than full-blown, Hare-certified psychopaths). In the preliminary analysis, they peered into the brains of male violent offenders who exhibited an unusually high amount of slow-wave sleep (the deep stuff) compared to "healthy" — non-psychopathic — controls. The effect was especially pronounced during stage four, the deepest stage of sleep. Three years later, the team analyzed homicidal women with ASPD. The same pattern emerged; subjects spent a greater-than-average chunk of their night in the deepest state of rest available without anesthetic (or divine) intervention.
More recently, in 2010, American psychologists ventured to prison (the default environment for monitoring antisocial brains at rest) to look at the relationship between sleep troubles, drug addiction and two different personality disorders, borderline personality (BPD) and antisocial personality disorder. While they found a clear link between poor sleep and BPD, they couldn't say the same of ASPD. When they eliminated drugs and depression from the mix, psychopathically oriented prisoners in the New York metropolitan area appeared to sleep normally. At least, that's what study subjects said — the experiment relied on subjective reports from prisoners.
While official, peer-reviewed science doesn't say much about snoozing psychopaths, the internet is less tight-lipped. A cursory look at dozens of psychopath-centric threads in online forums hints that the Finnish scientists were onto something. According to people who've shared beds with psychopaths, and gone on to write comments about it, the un-empathetic sleep well — but that doesn't mean they sleep normally.
Combing the psyopath forums
We don't have much reason to trust a stray comment on page six of a thread for ex-lovers of psychopaths. But, when assorted forums for psychopaths/sociopaths/ASPD-ers and their nearest and dearest offer similar depictions of the psychopath's "death sleep," it seems sensible to pay attention.
Collectively, forum comments suggest that psychopaths enter and leave sleep fast and fluidly, seamlessly transitioning between states of consciousness.
"Yes...it was more like he would pass out...instantly, with no preamble, just bam!" said one commenter on the website psychopathfree. "Which proves that they have no conscience, nothing bothers them. While asleep, he slept the sleep of the dead, and had a horrible snoring problem, which always kept me awake. He slept clutching me against him, squeezing me, and if I tried to roll over, he would squeeze me even tighter."
As the Finnish studies suggested, the "death sleep" isn't confined to men. In a thread on female sociopaths from a UK website, someone wrote: '"A friend on mine once shared a room at college with a woman who...would close her eyes and it was like an instant death sleep like a coma. But if you woke her up, her eyes would just open and she would say "what?" as if she had not been asleep at all."'
But, psychopaths appear to differ in the amount of sleep they need (or prefer). For some, a few hours a night does the job.
"He didn't need a lot of sleep, and would pop up ready to roll, as fresh as a daisy," wrote the above-quoted psychopathfree commenter, "no matter how much he had had to drink the night before, or no matter how late we had gone to bed, absolutely pristine."
Other psychopaths are more tied to sleep, according to users in a thread for victims of psychopaths or sociopaths.
"'Mine loved to sleep. He could fall right to sleep. He spent hours and hours sleeping. He had spent many years in and out of jail/prison so he slept with one eye opened or in other words 'on guard.'"
Then again, Donald Black, a doctor and author of "Bad Boys, Bad Men: Confronting Antisocial Personality Disorder (Sociopathy)," cautioned against drawing conclusions from anonymous anecdotes and studies on cherry-picked subjects. "I found a few articles on sleep [in ASPD]," Black said via email, "but the subject populations were not typical for ASPD (for example, forensic populations, or murderers). I would not hang my hat on any of the anecdotal information you have."
Is the dearth of research on psychopath sleep surprising? Well, if a group of people sleeps well, then it may not be the right target for limited resources, given how many people don't or can't sleep well. But, there is broader scientific value in unpacking the physiology underlying the psychopath brain, and how it differs from that of an empath. We'll be losing sleep over the answer.