Invented by an academic and popularised by social media, this sleep technique has long claimed to help people switch off their busy brains. When it recently worked for me, I became curious about how exactly it plays upon the mind.
If, like me, you are an anxious over-thinker, then lying in bed at night is prime time for ruminating. It doesn’t matter if I’m stressed or excited, I often can’t switch-off my brain. From breathing patterns to backwards counting, I’ve tried tons of sleep hacks. But none made a difference until I learned about cognitive shuffling.
The technique involves thinking of a random, emotionally neutral word, for example, “cake”. You take the first letter of the word, in this case “C”, and think of as many items or objects as you can that begin with the same letter, such as “car,” “carrot” and “cottage” – visualising each item as you go.
Once you can’t think of any more words beginning with C, you move on to the second letter. I rarely make it to the third.
It’s not a guaranteed fast-track to sleep – sometimes it still takes me a while – but it’s made enough of a difference that I’m still using the practice a year later. As are many others: hundreds of videos recommending cognitive shuffling have been posted on social media over the last few years, some receiving hundreds of thousands of views.
According to Alanna Hare, a consultant and specialist in sleep medicine at Royal Brompton Hospital in London, UK, cognitive shuffling is “super somnolent“. It deploys a push-and-pull mechanism on the mind, she says – both pulling you towards sleep while also quietening the intrusive worries that keep you awake.
But what is it exactly about cognitive shuffling that eases my brain this way? And why does this technique seem to work for me where other options have failed, even helping me fall back asleep if I wake in the night plagued by thoughts?
Imagine this: How cognitive shuffling induces sleep
Cognitive shuffling, or “serial diverse imagining”, was developed over 15 years ago by Luc P Beaudoin, an adjunct professor at Simon Fraser University in Canada.
It is based around Beaudoin’s theory of “somnolent information-processing“. This argues that people with insomnia often dwell on perturbing thought patterns – such as worrying, planning and rehearsing – which keep the brain alert. And that these mental processes can be countered with ones that help the brain feel “safe” enough to sleep.
Beaudoin tells mehe developed the concept of serial diverse imagining (focusing the brain on a series of neutral, random images) via “a long process of guessing about the mechanisms underlying sleep onset”, as well as “trial and error on myself”.
When he dug into the academic literature on tackling insomnia, he became particularly interested in a practicecalled imagery training, which involved vividly focusing on one image for a couple of minutes before switching to another. However, he also identified a problem with this existing approach: it was too slow.
“I figured that if people have an insistent worry, they would have difficulty focusing on a single image for a couple of minutes. Better to mix it up more quickly,” he says.
In 2016, Beaudoin and his colleagues tested the technique in a study of 154 university students who were struggling to sleep. One group was asked to use an app Beaudoin had developed that voices random words into your ear so you can hold their image in your minds’ eye. Another group journalled about their worries and possible solutions (a standard, evidence-based approach to insomnia).
The results showed the image shuffling approach was “just as effective as” at improving sleepiness. Plus it also had the advantage of being able to be done lying in bed.
Dream a little micro-dream
Cognitive shuffling works because it diverts your attention away from thoughts that interfere with falling asleep, says Eleni Kavaliotis, a registered psychologist and sleep researcher at Monash University, Australia.
“In doing so, it attempts to mimic the scattered, disconnected and random thought patterns the brain naturally starts to generate as you fall asleep.”
In this way, cognitive shuffling is designed to mirror a natural process called hypnagogic mentation that occurs in the boundary between wakefulness and sleep. Beaudoin calls these hallucinatory thoughts and fleeting images “micro-dreams”.
“The theory is that during cognitive shuffling the brain is in some relevant respects (not all) like normal sleep onset,” he says. In other words, “varied imagery is not just a byproduct of falling asleep, it’s a cue”.
Intrusive or stimulating thoughts can break this positive loop. Hare thus encourages her clients to think of neutral words when cognitive shuffling, such as animals or things you would buy in a supermarket, rather than anything that might stir up emotions. “Topics like politics and work can be alerting and make it even harder to sleep.”
Is cognitive shuffling for you?
When it comes to sleep techniques in general, what works for one person won’t necessarily work for another. “Different people respond to different strategies depending on how they experience stress and relate to their thoughts,” Kavaliotis says.
The classic idea of counting sheep doesn’t work for manyadults because we’re able to think about other things while counting, Hare says: “It’s not sufficiently counter-insomnolent because we can multitask.”
Yet neither is cognitive shuffling “a silver bullet that works for everyone”, says Beaudoin.
Some people also don’t like cognitive shuffling at all, Hare says. They can find word games confusing and difficult, or simply prefer number-focused techniques.
That said, Hare has seen success anecdotally with her clients. And Kavaliotis thinks that you can work on sleep strategies like you’d train a muscle. “The more you practice the stronger it can become and easier it can be to use,” she says.
A game-changing technique?
Beaudoin hopes that cognitive shuffling’s online popularity means that it’s helping people, but says it still needs more research. He would like to see studies comparing how it works for people who occasionally struggle to asleep (something he calls non-clinical insomnolence) as opposed to those with clinical insomnia. As well as studies comparing cognitive shuffling to other sleep techniques, such as mindfulness meditation.
Although cognitive shuffling has become a staple nighttime technique for me, sometimes it works better than others. When I’m particularly anxious, I have to work harder at it and it takes longer. But Hare says you shouldn’t worry too much about the odd night where it takes you a long time to fall asleep.
“Nobody sleeps from the minute they get into bed to the minute their alarm goes off every single night, that’s not normal,” she says. “If you’re falling asleep the minute your head hits the bed and sleeping through the night, you’re probably a bit sleep deprived.”
However, if you’re struggling with your sleep on a more frequent basis and it’s impacting you in the daytime, there may be an underlying problem that’s worth seeing a doctor about.
Chronic clinical insomnia requires more than just word games. But, for me, cognitive shuffling has been a game-changer.
