Cats had been as soon as believed to provide purrs by means of cyclic contractions of vocal fold muscle tissues, however a recent research suggests no such contractions are wanted. Anatomical research discovered a singular pad in cat vocal folds enabling them to provide low frequencies, prompting questions on our present understanding of cat purring.
A cat’s larynx can generate purring sounds with out cyclical neural enter.
Cats are vocal creatures: they meow, screech, and purr. From a voice manufacturing perspective, the meows and the screeches should not particular. Their sound is generated within the cat’s larynx or “voice box” similar to vocalization in people and plenty of different mammals.
In distinction, cat purrs had been lengthy believed to be distinctive. Research courting again half a century means that the purrs are produced by a particular mechanism – by means of cyclical contraction and leisure of the muscle tissues within the vocal folds inside the larynx, requiring fixed neural enter and management from the mind.
Unveiling the purring mechanism
A recent research, led by Austrian voice scientist Christian T. Herbst on the University of Vienna, now demonstrates that these cyclic muscle contractions should not wanted to generate cat purrs.
Data from a managed laboratory experiment reveals that the home cat larynx can produce impressively low-pitched sounds at purring frequencies with none cyclical neural enter or repetitive muscle contractions being wanted. The noticed sound manufacturing mechanism is strikingly much like human “creaky voice” or “vocal fry”.
“Anatomical investigations revealed a unique ‘pad’ within the cats’ vocal folds that may explain how such a small animal, weighing only a few kilograms, can regularly produce sounds at those incredibly low frequencies (20-30 Hz, or cycles per second) – far below even than lowest bass sounds produced by human voices,” says Herbst.
The research’s findings – whereas not constituting an outright falsification of the earlier idea – are a transparent indicator that the present understanding of cat purring is incomplete, and warrants additional analysis.
Reference: “Domestic cat larynges can produce purring frequencies without neural input” by Christian T. Herbst, Tamara Prigge, Maxime Garcia, Vit Hampala, Riccardo Hofer, Gerald E. Weissengruber, Jan G. Svec and W. Tecumseh Fitch, 3 October 2023, Current Biology.
DOI: 10.1016/j.cub.2023.09.014
