You Are Probably the Reason Your Dog Woke Up Last Night

A study published on October 7, 2026 in PLOS One put activity trackers on co-sleeping dogs and their owners, and the finding is a bit embarrassing for us. When one party stirred at night, it was more often the human who moved first, with the dog following, not the other way around.

Most owners assume the opposite. The dog shuffles, the duvet gets yanked, sleep is ruined. But the data points the other direction.

What the study actually measured

The researchers tracked nighttime movement patterns across dog-owner pairs using wearable activity monitors on both species. They found that dogs and owners do sync their sleep movements, but the causal direction matters. The human tends to be the one who disturbs first.

This doesn't mean your dog is a perfectly still sleep companion. Plenty of dogs are restless, dream visibly, or migrate across the bed over the course of a night. But the study suggests that if you're waking up tired and blaming the dog, you might be misreading what's happening.

Why owners get this backwards

Honestly, confirmation bias does a lot of work here. You feel the dog move. You register it consciously because it pulls you slightly out of sleep. Your own earlier movement, which triggered it, happened while you were less aware. So the dog becomes the culprit in the memory even when it wasn't in the data.

There's also something a bit uncomfortable about the alternative explanation: that your sleep is disrupted because you're a light and restless sleeper, and the dog is just along for the ride.

Does this mean co-sleeping is fine?

The study doesn't settle the question of whether sharing a bed with your dog is good or bad for sleep quality overall. That's a different measurement. What it does is challenge the specific assumption that the dog's movements are the primary source of nighttime disruption for the owner.

Whether you should co-sleep depends on a lot of things the study doesn't address: your dog's size, whether they're anxious or reactive at night, whether either of you has a health condition that makes fragmented sleep genuinely costly. A 40kg dog who jolts awake at passing foxes is a different conversation to a Whippet who curls up and barely breathes until 7am.

If your dog actually is restless at night

Some dogs are genuinely restless sleepers, and that's worth paying attention to, though not necessarily for the reasons you'd think. Nighttime restlessness in dogs can sometimes signal discomfort, pain, cognitive changes in older dogs, or anxiety. If your dog is pacing, repeatedly repositioning, or seems unable to settle, that's behavioural data, not just an annoyance.

Tailo's episode tracking is one way to log patterns like this over time, which is useful if you're trying to work out whether the restlessness is getting worse, is tied to specific nights, or seems correlated with anything else going on in your dog's routine or health.

If you're seeing consistent nighttime disturbance from your dog and it's not explained by obvious environmental triggers (a bin lorry, fireworks season, a new baby in the house), it's worth mentioning to your vet rather than just tolerating it.

The more useful reframe

The PLOS One finding is probably most valuable not as a verdict on co-sleeping but as a prompt to be more honest about what we're actually observing with our dogs. We're not neutral witnesses to our pets' behaviour. We interpret what we see through a lens of prior assumptions, and we tend to remember the moments that confirm what we already thought.

Your dog probably isn't ruining your sleep. You might be.