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”. (BBC)
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.