Mary Allen
Hardly anything is nicer than lying on the sofa and cuddling with a comfortably purring cat. But how does a cat actually purr? We’ll tell you.
So it’s not just that cats purr when they’re feeling particularly comfortable — some cats also start making the low-frequency noise when they’re feeling frightened, hurt, or stressed. They do this mainly to calm themselves down.
Purring makes you happy. And not only cat owners, but also the four-legged friends themselves.
A worthwhile side effect: Purring also promotes wound healing and bone growth. An injured cat that purrs is doing something to get well again as quickly as possible.
But where does the vibrating sound that makes us so happy come from? There are various theories about this:
The hyoid bone theory
The most likely way cats purr is the hyoid bone theory. The hyoid bone is located in the cat’s larynx and connects the tongue to the skull. When inhaling and exhaling, the cat pushes air past the hyoid bone, which creates the purr.
The larynx theory
This hypothesis assumes that cats are capable of rapid twitching of the larynx muscles and diaphragm. The contraction of the muscles around the larynx widens or narrows the airway, resulting in the typical purring noise.
The blood turbulence theory
This theory is now considered obsolete. However, for a time it was thought that the cat’s blood returning to the heart had to pass through a constriction in the diaphragm. It was assumed that this caused turbulence that produced the purring noise
The Vocal Cord Theory
This assumption, which is no longer considered probable, assumes that cats have skin folds behind their vocal cords that act as “false vocal cords”. When you inhale and exhale, these skin folds should vibrate, which creates a purr.