Last Updated on April 27, 2026 by admin
The slow blink isn’t a yawn. It isn’t sleepiness. It isn’t your cat being polite about wanting to go back to sleep on your laptop.
It’s a conversation. And researchers at the University of Sussex have now proven it works in both directions — including with cats who have never met you before.
Most cat owners watch this happen every day and miss it. Your cat looks at you across the room. Her eyes narrow. They half-close, then close all the way for a second or two, then open again slowly. You assume she’s drowsy. You go back to whatever you were doing.
She just told you she trusts you. And she was waiting for you to answer.
What’s Actually Happening
The behaviour is technically called the “slow blink sequence.” It usually starts with one or two half-blinks — partial eye narrowings — and ends in either a prolonged squint or a full closed-eye pause.
Closing your eyes around another animal is a vulnerability signal. A cat who shuts her eyes in front of you is telling you, in the most fundamental way her body knows how, that she does not need to watch you for threats.
This is not anthropomorphism. This is the conclusion of a 2020 study published in Scientific Reports, led by Dr. Tasmin Humphrey and Professor Karen McComb at the University of Sussex’s Mammal Communication and Cognition Research Group.
The Experiments That Settled It
The researchers ran two experiments.
In the first, owners were asked to sit about a meter from their own cat and slow-blink at them. The cats slow-blinked back significantly more often than they did when their owners were present but not signaling. The cats were reading the gesture and replying.
The second experiment was the surprising one. Researchers the cats had never seen before walked into the room and did the same slow blink. The cats — strangers in their own homes meeting strangers in lab coats — blinked back. Then they were more likely to approach the researcher’s outstretched hand.
A signal that worked between owner and cat also worked between a cat and someone she had no reason to trust. That is not a coincidence. That is communication.
It Even Predicts Adoption Speed
A separate 2020 paper in the journal Animals — Slow Blink Eye Closure in Shelter Cats Is Related to Quicker Adoption — followed 18 cats at the UK’s largest rehoming center, the National Cat Adoption Centre.
The cats who closed their eyes longer and more often when staff slow-blinked at them were rehomed faster than the cats who didn’t.
The slow blink isn’t just a private love note between one cat and one human. It’s a measurable behaviour that strangers respond to, often without knowing why they suddenly liked one cat in the row more than the others.
How to Try It Tonight
Sit a comfortable distance from your cat — three or four feet is plenty. Wait until she’s relaxed and looking in your general direction. Don’t stare. Cats read a hard, unblinking stare as a threat.
Soften your gaze. Let your eyelids drop halfway. Pause. Then close them all the way for one or two seconds. Open them slowly.
Watch her face. She might do nothing. She might do a half-blink back. She might give you the full squint. University of Sussex researchers noted that the more relaxed your face is, the more likely the response.
If she does it back, you have just had a conversation in a language that crosses species. That is one of the only confirmed forms of two-way emotional signaling between humans and a non-primate animal.
What This Changes
The next time your cat sits across the room, looks at you, and slowly closes her eyes — she isn’t drifting off.
She’s saying something. And now you know how to answer.
Does your cat slow-blink at you? Tell us what it looks like in the comments. 👇