Last Updated on May 28, 2026 by admin
You sit on the couch. Your cat, halfway across the room, looks at you, half-closes both eyes, holds it for a beat, and looks away.
That gesture has a name now.
It is called the slow blink, and in 2020 a team of psychologists from the University of Sussex and the University of Portsmouth ran the first proper experiments on it. They published the results in Scientific Reports.
Most people read the slow blink wrong.
If you have ever caught your cat doing it from the rug while you eat dinner, you may have assumed she was getting drowsy, or simply blinking, or losing interest in you. None of those is quite right. What you were actually watching, according to the Sussex research, was the closest behavioural equivalent a cat has to a smile — and it was aimed at you on purpose.
Here is what the team actually did.
Dr Tasmin Humphrey, working with Professor Karen McComb, ran two experiments published in Scientific Reports. In the first, owners sat on the floor in their own homes and either slow-blinked at their cats or held a neutral face. Cats slow-blinked back significantly more often when their owners slow-blinked first.
In the second experiment, an unfamiliar researcher slow-blinked at strangers’ cats. The cats were more likely to approach that stranger, and more likely to accept an extended hand, than after the same researcher had shown a neutral expression.
That is not a small finding. It means the slow blink isn’t a private dialect between you and your cat — it is a recognised feline signal that any human can deploy, and that any cat can read.
What is actually happening when a cat does it?
Humphrey and McComb compare the slow blink to the Duchenne smile in humans — the involuntary smile that reaches the eyes, the one a person cannot fake. In cats, the muscles around the eye narrow and soften in a way that, in the wild, would only be safe to do around something a cat trusts. A cat with predators around does not close its eyes. A cat closing its eyes at you is, in a quiet feline way, saying: I do not need to watch you right now.
The signal travels in both directions, and the practical use is real. A follow-up study in the journal Animals found that shelter cats that slow-blinked at humans were adopted faster than cats that didn’t. A muscle movement around the eyes was, measurably, changing outcomes for cats waiting in cages.
So here is what to do with this.
The next time you and your cat are in the same room and she catches your eye, don’t stare. Staring, to a cat, reads as a threat. Instead, look softly in her direction. Let your own eyelids drop about halfway. Hold them there for a second or two. Then close them slowly and reopen them, just as slowly.
Then wait.
Some cats will mirror it back the first time. Some take a few rounds. Older cats and shy cats often respond more readily than confident, busy ones — they have more to gain from telling you they feel safe. If she half-closes her eyes back at you, that is not a coincidence. That is a conversation, conducted entirely in muscles around the eye, between two species that otherwise share almost no language.
The University of Sussex’s own announcement about the study called the slow blink “the cat equivalent of a smile.” The researchers were careful with that line, but it’s the one that stuck — and watching for it changes how you see your own cat across a room.
Try it tonight. Most cats living with humans they trust will offer one within a few minutes, especially right before a nap, right after dinner, or any time the house is quiet and the lights are low.
Has your cat ever slow-blinked at you? Drop a 😌 in the comments if she has.