2018-11-14 / Columnists

Pets, Pets, Pets

Purrfection! Cats captivate us with their purring—a combo of vibration and sound that makes many people melt. Purring is unique to felines. Not only our pets. Bigger cats such as tigers, lions, leopards, panthers, cheetahs and jaguars purr too.

However, jungle cats only do so when breathing out, unlike domestic cats who purr when they inhale and exhale. The hyoid bone, which sits in the throat and provides support for the tongue and larynx, might make the difference. While purring domestic cats tend to have rigid hyoid bones, bigger cats have more flexible, less bony hyoids that let them roar but may keep them from purring as well as Fluffy.

How Cats Purr: Scientists used to think purrs were the sound of blood surging through cats’ vena cava, the large vein that carries blood from the lower part of the body into the heart. More recent research is based on photos of the muscles of the larynx. Current thinking is the purring sound is produced by rhythmic contractions of the cat’s larynx muscles and diaphragm.

A cat’s purr begins in the brain. A neural oscillator sends messages to the larynx causing its muscles to begin to twitch. Contractions of the muscles and vocal chords open and close the glottis (the thin opening between the vocal chords at the top of the larynx). As the cat breathes in and out, air hits the vibrating larynx muscles in the throat producing the purring sound.

Each cat will purr with his own consistent pattern and at a consistent frequency usually between 25 and 150Hz (hertz) per second. The frequency is controlled by the autonomic nervous system, which also regulates the activity of the diaphragm while the larynx constricts and relaxes. Despite autonomic nervous system involvement, cats do have conscious control over purring.

Why Cats Purr: Newborn kittens are blind and deaf, so purring is the first form of communication between mother and kitten. We all know cats purr when they are happy. But they also purr when they are frightened, threatened, sick or in pain. I once drove a dying kitten to the vet. He purred during the ride and expired before we got there.

Purring releases endorphins and is self-soothing and a stress relief to felines. Cats may even purr in an attempt to soothe a potential enemy when they know there’s no way to escape. There are two other reasons cats purr that may surprise you. Read on.

A Purr Ploy: “Feed me!” It’s the “purrfect” ploy. Cats may not do what we want them to do, but they are vocally adept at manipulating us to do what they want, especially when it comes to providing room service. There is scientific proof that reveals the feline modus operandi. It seems conniving cats urge owners to fill their food bowls by sending a specific, mixed signal that people find hard to ignore.

A 2009 study at the University of Sussex in the United Kingdom found that some cats have a specialized purr referred to as the “soliciting purr.” Cats embed this cry within their low-pitched purr. The frequency of the embedded cry is similar to that of a crying infant. Using the falsetto cry inside their usual, pleasant purr lets cats send a subliminal message of urgency to their “gullible” owners who promptly feed them. In the Sussex study, men were as responsive to the cat cries as women. You might say these cats appear to be exploiting humans’ innate tendencies to nurture their own offspring.

Purring to Heal: Scientists like Elizabeth von Muggenthaler, a bioacoustics expert, believe cats also purr to heal themselves. Purrs vibrate at 25-150HZ, which is the frequency that assists in physical healing and bone mending. Even as a cat is napping or resting, she might be keeping her bones strong and healthy.

There’s additional evidence that the series of vibrations caused by purring can repair muscles and tendons, ease breathing, and reduce pain and swelling. Cats rarely suffer from bone or joint-related diseases like hip dysplasia or ligament issues. You do not hear of cats developing bone cancers as often as dogs do. There is a popular saying between veterinarians: “If you put a cat and a bunch of broken bones in the same room, the bones will heal.” Medical researchers are looking into using devices that emit a purr-like sound frequency on humans who require bone-density therapy or astronauts who must remain weightless for long periods.

Bone and joint problems may not be the only illnesses helped by a cat’s purring ability. Respiratory problems linked with heart disease are not as common in cats as they are in dogs. In fact, respiratory problems resolve quickly with cats once purring is activated. Large skin-tissue grafts take quickly in cats. Domestic cats also tend to be less prone to postoperative complications following surgery.

Some people are convinced the healing power of purring helps the cats’ owners too. Studies show cats do a better job of relieving stress and lowering blood pressure than other pets. A 10-year study at the University of Minnesota Stroke Center found cat owners were 40 percent less likely to have heart attacks than non-cat owners. Perhaps purring plays a role in that.

The auditory effect of the cat’s purr near us makes us feel more relaxed since we associate purring with contentment. We begin stroking the purring cat which comforts us too. Many individuals swear they can ease or completely eliminate their migraine headaches simply by lying down with a purring cat next to their head.

St. Francis of Assisi (c. 1181-1226) supposedly said: “A cat purring on your lap is more healing than any drug in the world, as the vibrations you receiving are of pure love and contentment.” If so, the patron saint of pets was on to the healing power of the purr many centuries before these researchers.

Cats for Adoption at Babylon Shelter 631-643-9270 80 New Highway, N. Amityville: Amber 8-485 is a gorgeous tabbico kitten born at the end of April. She prefers a quiet home. Cosmos 8-421 is blossoming in a free roamer room off the lobby of the new shelter. This one-year-old tuxedo was abandoned at an animal hospital. Open House at the shelter will be Sat. Nov. 17 from 10 a.m. to 3 p.m.; enjoy tours, raffles, refreshments.

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