Cats get called aloof, like they are choosing distance on purpose. Often it is simpler than that: humans miss the signals because cat communication is quiet and facial.
One of the most useful cues is the slow blink, and a peer‑reviewed study suggests it is a real “friendly message” cats understand.
The “Cat Smile” You’ve Probably Missed
Imagine a cat resting on a sofa, watching you with eyelids lowered, then closing its eyes in a long, lazy blink.
Behaviorists have long linked that expression with comfort. The eyes narrow, the blink happens slowly, and the face looks loose rather than alert.
Among many animals, a hard stare can feel intense. Slow blinking softens eye contact, which may make the situation feel safer and more relaxed. People compare it to a human smile that signals warmth without being pushy. It is small, but cats are specialists in small.
Pet advice columns have recommended “blink at your cat” for years. What was missing was a careful test that separated chance blinking from a response to a human signal.
Researchers at the University of Sussex set out to check it under controlled conditions.
Two Experiments, One Simple Signal
Psychologists Karen McComb and Tasmin Humphrey led the work at Sussex in the United Kingdom.
Their findings appeared in Scientific Reports, in what the authors describe as the first experimental study focused on slow blinking as cat–human communication (McComb, Humphrey, and colleagues, 2020).
In Experiment 1, the team observed 21 cats from 14 homes, letting the cats stay in their usual environment. Owners sat roughly one meter away. When a cat looked toward them, the owner performed a slow blink.
In a control condition, the owner stayed neutral and did not engage. Video recordings captured both the person’s face and the cat’s reaction.
Cats were significantly more likely to slow blink back during the slow‑blink interaction than during the no‑interaction control. That “blink back” matters, because it suggests the cat is not just sleepy; it is responding in a social loop.
Experiment 2 asked a tougher question: does the signal work with an unfamiliar person? The researchers worked with 24 cats from eight homes.
In one condition, a researcher slow blinked and then extended a hand, giving the cat a chance to approach. In the control condition, the researcher looked at the cat without blinking, creating a steady stare.
The difference showed up again. Cats slow blinked more in response to the slow blink, and they were more likely to approach the researcher afterward compared with the no‑blink condition.
In everyday terms, the “cat smile” did not just get mirrored; it made cats more willing to close the distance.
What the Findings Suggest About Cat Social Intelligence
The cleanest interpretation is that slow blinking signals non‑aggression or benign intent.
Eyes are powerful social tools, and reducing the intensity of eye contact can lower tension. From the cat’s point of view, the human face becomes easier to read and less demanding.
There is another angle worth taking seriously: cats may have learned that humans react well to slow blinking. If people tend to speak softly, offer treats, or pause their movement when a cat slow blinks, the behavior could be reinforced over time.
The Sussex experiments cannot fully separate instinct from learning, but they show that the signal has a measurable effect in the moment.
These results also fit a broader shift in cat research. Cats are not dogs in smaller bodies; they have their own social style.
In one Scientific Reports study, cats distinguished their own names from other spoken words, even when the speaker was a familiar person (Saito et al., 2019).
Other studies report that cats adjust their behavior in response to human emotional cues, suggesting they track our routines and mood changes more than we assume (Merola et al., 2015, Animal Cognition).
Another point the Sussex paper touches indirectly is the idea of matching.
In day‑to‑day life, cats tend to do better with people who move slowly, give them choice, and notice small signals.
Several studies on cat–owner relationships, including questionnaire-based work on feline personality, suggest cats show more affiliative behavior when humans are consistent and responsive rather than loud or unpredictable.
That can look like “mirroring,” even if it is really good social learning. The dog comparison trips people up here: dogs are built for obvious displays, while cats often signal through distance and micro‑expressions.
Slow blinking fits that quieter style and gives humans a clear entry point without forcing touch or invading personal space.
So when a cat avoids direct attention, it may not be rejecting connection. It may be using a calmer, lower‑volume system. Slow blinking, in that framework, is not a trick. It is vocabulary.
Using Slow Blinks the Right Way
If you want to use this signal, keep the setup simple. Face the cat gently, without leaning in. Narrow your eyes slightly, close them slowly for a couple of seconds, and reopen at an easy pace. Then stop and wait. The pause is part of the message.
A relaxed cat may return the slow blink, hold a soft gaze, or approach. A cat that turns away or walks off may be saying it needs more space, and that is useful feedback too. The goal is to offer comfort, not to force interaction.
The practical upside is obvious in places that feel unfamiliar to cats. Shelters, veterinary clinics, foster homes, and newly adopted households all involve strange sounds and smells.
A brief slow blink can be a low‑effort way for staff and visitors to appear less intense and invite a cat to engage on its own terms. It will not solve every behavior issue, but it can make first contact smoother.
What stands out about this study is its simplicity. It takes a common, everyday observation and tests it with controls, recordings, and repeatable conditions.
The message for cat owners is straightforward: if you want to say “I’m friendly” in cat language, start with your eyes.
Sources
How to build rap-paw with your cat
The Psychological Study of Smiling
If You Find Cats Antisocial, It’s More Likely You Being a Jerk, According to Science
How Depressive Moods Affect the Behavior of Singly Living Persons Toward their Cats
If Your Cat’s Neurotic, Scientists Say It’s Probably Just Mirroring You
Study Shows Our Cats Do Know Their Names, They Just Choose to Ignore Us
Cats Do Bond Securely to Their Humans – Maybe Even More So Than Dogs
The role of cat eye narrowing movements in cat–human communication