I am going to rely on my own observations to answer the question. I’m sure that almost all other cat owners have observed the same thing: when a domestic cat dreams their whiskers twitch, their ears might move, they might make the odd noise and their body sometimes twitches, including their legs. It appears to me that when my cat dreams he is reliving a slightly difficult or even bad experience that he has had during the day or previous days. It’s clear that he is having a minor nightmare or, to put it more mildly, a bad dream. But perhaps the purpose is to reprocess these experiences. Perhaps the purpose of these dreams is to come to terms with the bad experiences and to better understand them.
I would not expect him to only have these sorts of dreams. He may have dreams which are quite pleasant on occasions and during which he does not move. And, also, it occurs to me that the dreams that my cat has are similar to those that I have. Like everyone else my dreams seem to reenact my fears. For example, in some semi-nightmares I struggle to catch a train because there is always some barrier between me and my goal. Or I struggle to walk home through an urban environment because I constantly get lost. These seem to reflect underlying fears or anxieties about achieving goals and constantly being faced with barriers.
I see no reason to believe why domestic cats don’t have the same sort of dreams and the same reasons for them. The physiology of the domestic cat is, at a fundamental level, very similar to that of humans. I have failed to find scientific studies on domestic cat dreaming. Although there are a lot of articles on it, the authors take a common-sense approach as I have.
Dreaming occurs during REM sleep. The eyes move rapidly and the brain’s activity is similar to that of an awake state. Young animals have longer sessions of REM sleep than older animals. This might be because they have more information to process as their experiences during the day are new to them.
Dr. Katy Nelson, the senior veterinarian at Chewy (online pet store), in an interview with Reader’s Digest, agrees with me. She said: “If they went outside and saw a bird and another kitty friend, those images are likely what is playing through their minds during sleep. Perhaps there are even dreaming about you, a delicious dinner, and the pens and chap stick that they pushed off your table just so they can watch them fall.”
Obviously, like me, she’s speculating but I think a common-sense approach to providing an answer to the question in the title is the right approach. She also agrees that when we see our cat move during sleep it is a sign that they are dreaming. Once again this is a common-sense approach. In fact, because we can’t ask our cat what they’re dreaming, the best way to judge what is happening is through their movements and these indicate to me that they are often struggling with something and reliving past experiences which made them anxious.
SOME MORE ON FELINE DREAMING:
I don’t remember where, or even when, I read this. I’ve had nothing much to do but read since my poor health-enforced my retirement in 1985. But I read that an experiment was conducted on a number of cats, apparently all at the same time, and it disabled, I forget how, or whether temporarily or permanently, the thing in their brains which immobilizes them (as well as all mammals) and prevents them from acting out their dreams. All of the cats, when they entered REM or dreaming sleep, began to stalk invisible,to the experimenters at least, mice. I disapprove of any research that would cause suffering or permanently disable an animal in any way, and I don’t remember being offended about the experiment. So either the effect was temporary or my memory is faulty on the point. So the implication is that the cats dreams were having them practice their hunting skills.