Your cat looks so sweet curled up in his cozy bed. You can't help but laugh when you see his little paws and whiskers start to twitch. It's likely that he's having an exciting dream, perhaps about chasing after a mouse or his favorite catnip toy. Dreaming is not isolated to humans, and kitty has sweet dreams, too.
Cats spend an extraordinary amount of time snoozing. Your cat can clock up to 16 hours of sleep per day. This means your cat is asleep for more than half of his entire life. It's common for cats to nap, but only fall into a light sleep. As soon as you scratch kitty's ears or he hears the can opener going, he can jolt awake. However, he can fall into a much deeper sleep, called REM, or rapid eye movement. It's during this deep slumber that you'll see kitty moving his paws or twitching his whiskers as if he's chasing some phantom prey.
You're likely familiar with REM sleep in humans. It's the time when you dream vividly. During REM, brain activity increases and your eyes dart around in all directions beneath closed lids. This type of sleep is found in most mammals and birds, and isn't unique to humans. Dogs, cats and rats all dream. You'll go into REM sleep about every 90 minutes, but your cat dreams more than you. A cat will enter REM sleep about every 25 minutes. Since your cat snoozes so much of the day away, he's doing a lot of dreaming.
During REM sleep, your muscles are temporarily paralyzed, called muscle atonia. This is to keep you from acting our your dreams in your sleep. But anyone who has ever sleepwalked or talked in their sleep knows this isn't perfect. Sometimes you can lose some muscle atonia during sleep, allowing for movement. It's likely the same thing is happening to your cat. When his feet twitch or his tail quivers, it's because his body is acting out his dream.
It's perfectly normal if your cat gets a little twitchy when he's having a good nap. Sometimes a twitchy cat isn't because he's dreaming of hunting down a prized trophy. It could be a sign that your cat is having a small seizure. If his entire body goes completely stiff or he's acting sick and throwing up, it's time to visit his vet. If the twitching is small and only occurs while your cat is sleeping, it's likely he's just having a thrilling dream.