There are few things more delicate than the affection of a cat.

They play us humans hot and cold, all purrs and pat-seeking one minute – the next, a unique level of aloofness, best demonstrated as they skulk out the door away from us.

In the past couple of years, science is has finally started asking the big question: Do cats at all care for us?

The latest study suggests maybe, but it helps if you learn and practise the cat equivalent of the secret Masonic handshake.

Who blinks first?

The research, by animal behaviour scientists from the University of Sussex, has “shown for the first time that it is possible to build rapport with a cat by using an eye-narrowing technique with them”.

This cat is saying: “Do this and you’ll be as attractive to me as a sardine.”

The researchers say that this “eye-narrowing action by humans generates something popularly known as a cat smile – the so-called ‘slow blink’ – and seems to make the human more attractive to the cat”.

Eye-narrowing movements in cats have some parallels with the genuine smile in humans (known as the Duchenne smile), as well as eye-narrowing movements given in positive situations in some other species.

A Duchenne smile reaches your eyes and makes the corners wrinkle. It’s touted as the smile that shows us at our most authentically happy. As opposed to the fake one you wear at parties.

For once, a cat seems to be trying too hard to win you over. Savour the moment.

Professor Karen McComb, from the School of Psychology at the University of Sussex, who supervised the work, in a prepared statement said: “As someone who has both studied animal behaviour and is a cat owner, it’s great to be able to show that cats and humans can communicate in this way. It’s something that many cat owners had already suspected, so it’s exciting to have found evidence for it.

“This study is the first to experimentally investigate the role of slow blinking in cat-human communication.

“And it is something you can try yourself with your own cat at home, or with cats you meet in the street. It’s a great way of enhancing the bond you have with cats.

“Try narrowing your eyes at them as you would in a relaxed smile, followed by closing your eyes for a couple of seconds. You’ll find they respond in the same way themselves and you can start a sort of conversation.”

Two experiments, no saucers of milk involved

According to a statement from the University of Sussex, two experiments were conducted to explore the significance of the slow blink in cat-human communication.

• The first experiment included a total of 21 cats from 14 different households. Fourteen different owners participated
• Ten of the cats were male and 11 of the cats were female, with cat age ranging from an estimated 0.45 to 16 years
• The experiments took place in each cat’s home. The psychologist advised the cat’s owner on how to slow blink. Once the cat had settled down in one place, the psychologist asked the owner to either sit approximately one metre away from the cat
• The second experiment  included a total of 24 additional cats. Twelve cats were male and 12 cats were female, with cat age ranging from an estimated 1-17 years old
• The cats included in the final analyses were from eight different households
• In this experiment, the researcher, who was unfamiliar to the cat, either slow blinked at the cat or adopted a neutral face without direct eye contact
• This experiment also tested which context the cats preferred to approach the unfamiliar experimenter, by them offering the cat a flat hand with palm faced upwards whilst sat or crouched directly opposite the cat. Both experiments were video recorded.

And the conclusion?

The study found:

1. Cats were more likely to slow blink at their owners if their owners had slowed blinked at them, compared to when the owner was present in the room but not delivering a slow blink stimulus
2. Cats were more likely to slow blink when an unfamiliar experimenter slow blinked at them, compared to when they had maintained a neutral expression
3. Cats preferred to approach an experimenter after they had slow blinked at the cat than if they had maintained a neutral expression.

Of course, cats might be programmed to behave in that friendly slow blink fashion. But they might find ways to disguise it.

Tasmin Humphrey, a PhD student in the School of Psychology at the University of Sussex, and corresponding author of the study said: “In terms of why cats behave in this way, it could be argued that cats developed the slow-blink behaviours because humans perceived slow blinking as positive.

“Cats may have learned that humans reward them for responding to slow blinking. It is also possible that slow blinking in cats began as a way to interrupt an unbroken stare, which is potentially threatening in social interaction.”

Cat psychology and previous research

In the paper, the authors lament that “the psychology of cats hasn’t been studied as extensively as dogs”, but what is already known includes:

• That cats have been shown to attract and manipulate human attention effectively through ‘solicitation purring’
• That cats can discriminate their name from other words, even when unfamiliar humans are calling
• That cats may be sensitive to human emotional cues, and will rub or butt their head against an owner who feels sad.

Of course the latter behaviour could mean: “Don’t just sit their wallowing in the couch. If my food bowl isn’t attended to, like right now, there will be serious trouble.”