 Owing to the close similarity between play and hunting , cats prefer to play with objects that resemble prey , such as small furry toys that move rapidly , but rapidly lose interest ( they become habituated ) in a toy they have played with before . Cats also tend to play with toys more when they are hungry . String is often used as a toy , but if it is eaten , it can become caught at the base of the cat 's tongue and then move into the intestines , a medical emergency which can cause serious illness , even death . Owing to the risks posed by cats eating string , it is sometimes replaced with a laser pointer 's dot , which cats may chase . There are several important issues related to using a laser with a cat ; first most , lasers can cause blindness in cats , even lasers which are sold as " eye safe " can actually be of much higher power of that proclaimed and can cause damages to the eyes . In addition , the cat thinks of the laser point as prey , but gets frustrated as he is unable to catch it . 
