Most people have a version of it: the moment the lights go out and the brain decides it’s finally time to relitigate every unresolved problem, upcoming deadline, and awkward conversation from 2019. Counting sheep has never fixed it. Neither has telling yourself to relax. But a sleep researcher at Simon Fraser University spent decades developing a technique designed specifically for this moment — and it has been quietly accumulating evidence ever since.
It’s called cognitive shuffling. And it works by tricking your brain into doing something it was already going to do anyway.
The Window Between Waking and Sleep
Sleep doesn’t flip on like a switch. There’s a transitional zone — the hypnagogic state — where the brain begins loosening its grip on logical, sequential thinking and starts generating something stranger: fragmentary images, half-formed scenes, disconnected flashes of random objects and places. If you’ve ever been startled awake by a sudden falling sensation, or noticed yourself briefly “seeing” something that wasn’t there as you drifted off, that’s hypnagogia.
Cognitive scientist Dr. Luc Beaudoin spent years studying this window and concluded that the brain interprets these micro-dreams as a signal that it’s safe to let go of wakefulness. The problem for poor sleepers is that racing, coherent, purposeful thinking — the kind that runs through tomorrow’s meeting or rehearses a difficult conversation — actively delays that transition. The brain stays alert precisely because the thoughts feel important.
Shuffling a Mental Deck of Cards
The technique Beaudoin developed asks you to generate the opposite of coherent thinking. You choose a random, emotionally neutral word — “candle,” say — and mentally picture a series of unrelated objects starting with each letter. C: a cake, a car, a castle. A: an acorn, an anchor. N: a napkin, a needle. You hold each image briefly, then move on, never lingering long enough to build a narrative around any of them.
The mental randomness isn’t just distraction — it’s a deliberate imitation of what the brain does naturally at sleep onset. By manually producing the same fragmented, non-linear imagery that precedes sleep, you’re essentially signaling to the brain that the transition is already underway. The brain registers the micro-dreams as permission to continue shutting down.
Sleep medicine consultant Dr. Alanna Hare of Royal Brompton Hospital in London describes the technique as deploying a push-and-pull mechanism — nudging the brain toward sleep while simultaneously quieting the worries that prevent it.
How It Held Up Against a Proven Method
Beaudoin’s 2016 study recruited 154 participants experiencing sleep difficulties and randomly assigned them to one of two approaches. One group practiced constructive worry time — a clinically validated technique involving journaling about problems a few hours before bed. The other group tried cognitive shuffling at bedtime. The results placed the two methods on roughly equal footing, with one practical advantage: constructive worry time requires setting aside time earlier in the evening. Cognitive shuffling can be done in bed, in the dark, the moment you actually need it. Practitioners typically report falling asleep within five to fifteen minutes.
The underlying theory, which Beaudoin calls somnolent information processing, holds that the brain has a kind of sleep onset control system — and that mental perturbance, the technical term for racing thoughts, is one of the primary things that disrupts it. Cognitive shuffling is designed to work within that system rather than fight it.
Why Anxious Brains Respond to It
The technique sits in a particular cognitive sweet spot. It requires just enough mental engagement to block intrusive thoughts from taking hold, but not enough to trigger executive function — the effortful, goal-directed thinking that keeps the brain alert. You won’t solve any problems while picturing a napkin and a needle. That’s precisely the point.
For people whose nighttime thinking tends toward rumination, this matters. The American Academy of Sleep Medicine lists intrusive thoughts and repetitive worry among the most common barriers to sleep onset, and recommends cognitive distraction techniques that redirect attention away from stressors. Cognitive shuffling formalizes that redirection with a specific, repeatable structure.
A Technique You Can Try Tonight
Start with any neutral word — nothing emotionally loaded, nothing that leads directly to something you’re anxious about. Work through each letter slowly, visualizing one image at a time. Don’t rush. If your mind wanders back to something stressful, don’t resist it; just return to the next letter and the next image.
Most people who report success with the technique say they rarely make it past the second or third letter of the first word before drifting off. The brain, it turns out, doesn’t need much encouragement once you stop giving it something coherent to chew on.
Beaudoin notes that cognitive shuffling works best as part of broader sleep hygiene — consistent sleep times, a dark and cool room, screens off before bed. No mental technique, however well-designed, cancels out a double espresso at 9pm. But for the specific problem of a brain that won’t quiet down at the end of the day, this is one of the more elegant solutions sleep science has produced.