Numerous studies have demonstrated that petting a cat can improve a person’s psychological and physical health, including lowering blood pressure. However, petting is a two-way street and it turns out that it also provides medical benefits to your cat.

Veterinarians Andrea Looney and Anna Glazer, while at the Cornell Feline Health Center, performed an experiment where they attached a tiny blood pressure cuff to a cat’s leg. After just five minutes of petting by a person, the cat’s blood pressure dropped 25 points.

In another experiment, Dr. Kathy Carlstead, currently a research scientist at the Honolulu Zoo, measured the cortisol levels in two groups of cats. (Cortisol is a hormone that increases when a cat is stressed. If cortisol levels are elevated for too long, it will weaken the cat’s immune system and increase her chance of getting ill.) One group’s routine continued as normal, which included being petted and talked to, while the other group of cats’ routine was changed and they got no touching or talking. The results were that the cats who were denied petting and being spoken to had much higher stress and cortisol levels. Carlstead believes the change in petting is what caused the increase in cortisol. “Part of it is these cats were used to being petted and talked to, and once you deny it, that change in caretaking was stressful,” says Carlstead.

In a different study, Carlstead measured the cortisol levels of cats by inserting a catheter in their leg — a stressful procedure. Cats who were not socialized to people and would not allow petting had high rises in cortisol, but amazingly, the cats who had been socialized to people and allowed petting had no rise in their cortisol levels. Petting alone was powerful enough to eliminate most of their stress.

So we know petting has great benefits for both person and cat. Where, then, is the best place to pet your cat? Drs. Susan Soennichsen and Arnold Chamove from the University of Massey in New Zealand conducted a study to find out. Their results show the place cats enjoyed being petted the most was the side of the head, between the eyes and the ears. The researchers believe the cats prefer this area because a major scent gland is located there, and it enables the cat to deposit her scent on our hand.

Dr. Penny Bernstein of Kent State University, Stark Campus, conducted a similar study. She found most people could tell when their cat was asking to be petted, and some cats had specific places in the house where they wanted the petting to occur. “Its more like they’re training you,” Bernstein says. “They know that if they do certain things, they’ll get this reward. Except we didn’t train them, they trained us.”