cats, kitten, purring
A cat's purr is still a puzzle to scientists. (Image credit: Kitten image via Shutterstock)

Unlike other cat noises, purring occurs during the entire breathing cycle — inhale and exhale. A meow, on the other hand, is done only during exhalation. But how exactly do cats purr?

Scientists are still puzzled over the exact mechanism of purring. But the most accepted idea is that a region of the cat ’s brain signals the muscles that make up its voice box, called the laryngeal muscles, to vibrate.

Simultaneously, Fluffy is inhaling and exhaling, sending a stream of air through the vocal cords. Together these two actions cause the vocal cords to vibrate, creating one purr-fect feline sound that pleases many humans — and makes dog lovers of the rest.

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Michelle Bryner
Michelle writes about technology and chemistry for Live Science. She has a Bachelor of Science in Chemistry from the Salisbury University, a Bachelor of Chemical Engineering from the University of Delaware and a degree in Science Journalism from New York University. She is an active Muay Thai kickboxer at Five Points Academy and loves exploring NYC with friends.