why do cats purr when they sleep

Cats purr when they sleep primarily because they feel relaxed, content, and secure. The purring during sleep can also be linked to dreaming during REM sleep, as cats might purr in reaction to a pleasant dream or emotional experience. Additionally, purring has therapeutic effects at certain frequencies, which may promote healing, muscle relaxation, and bone regeneration even while the cat is asleep. Cats' ability to purr during sleep also relates to their light sleeping patterns, where they can maintain some awareness of their surroundings yet remain relaxed enough to purr.