Cat Slow Blinking: The Science Behind the Famous 'Cat Kiss'
The Slow Blink Is One of the Most Important Cat Behaviors You Can Learn
Among the many signals in the feline body language repertoire, the slow blink holds a special place. Often called the "cat kiss" or "eye kiss" by cat owners, the slow, deliberate closing and opening of the eyes is one of the clearest expressions of trust and positive emotion that cats display toward other cats and humans. More recently, the scientific community has taken a closer look at this behavior with surprising and heartwarming results.
What Slow Blinking Communicates
In feline body language, direct eye contact is a potential threat signal — a hard, unblinking stare between cats typically precedes conflict. The slow blink is, in some sense, the opposite of a stare: a deliberate relaxation of the gaze that communicates non-threat and positive affect. When a cat slow-blinks at you, they are essentially signaling that they feel safe enough in your presence to voluntarily reduce their visual vigilance — a meaningful act for a prey animal that is always monitoring for danger.
The 2020 Scientific Study
In 2020, researchers at the University of Sussex published a peer-reviewed study in Scientific Reports that provided the first controlled experimental evidence for slow blinking as a meaningful communication signal. The study found two key results: first, cats approached unfamiliar humans more readily when those humans had slow-blinked at them compared to a neutral expression. Second, cats slow-blinked more toward humans who had slow-blinked at them first. This bidirectionality is significant — the behavior functions as a genuine communication exchange, not just a coincidental eye movement.
How to Slow Blink at Your Cat
The technique is simple. Make comfortable, relaxed eye contact with your cat — not a hard stare, just a gentle gaze. Then slowly close your eyes halfway, hold for a second or two, then slowly reopen them. You can repeat two or three times. Many cats will slow-blink back within a few seconds. Some will turn away, which also indicates comfort (looking away is a non-threat signal, the feline equivalent of a comfortable silence).
The key is that your own expression should be genuinely relaxed — a forced slow blink while tense or anxious may not convey the same signal. Cat behavior experts note that the emotional state of the human seems to matter, not just the mechanical eye movement.
Slow Blinking with Unfamiliar Cats
The Sussex study's finding that slow blinking facilitates approach from unfamiliar cats has practical applications. If you encounter a shelter cat, a neighbor's cat, or a stray that seems uncertain, slow blinking can help signal your benign intentions more effectively than extending a hand. This is increasingly being used in shelter environments to help cats be more comfortable with unfamiliar humans during adoption visits.
Other Positive Eye Signals in Cats
Soft, heavy-lidded eyes indicate relaxation and comfort — the opposite of the wide, dilated eyes of fear or intense focus. Half-closed eyes combined with a relaxed posture and slow breathing are some of the clearest possible signals that your cat is content and at ease. Learning these expressions is part of developing the deeper communication that makes life with cats so rewarding.