A cat’s short-term memory can last up to 16 hours, and long-term memory can last for months or even years, or possibly a lifetime. A cat’s long-term memory is a repetition of short-term memory. Cats between 2 and 7 weeks old have their prime memory time, so adopting them during this period is the easiest time for them to remember.

But one characteristic of cats’ memory is that their interests are very obvious. In other words, only things that cats are interested in will be remembered immediately and for a long time. Cats will not bother to remember things that they are not interested in at all.

When cats get old, they may also suffer from Alzheimer's disease. They will urinate everywhere, forget how to use the litter box, and even forget their owners. Because their brains have declined by this time, but not because their memory is bad. When the owner leaves the cat for a period of time, don't worry that the cat will forget you. You just need to spend more time with them and gradually become familiar with them again.