Sensory Memory

This is your brain’s automatic memory, where all sensory input is held for just an instant (a second or less). If, however, you perceive something unusual in an image or sound (say, a picture of a dog with three legs and two tails), and/or you decide to pay attention to that dog, then the information in your sensory memory will not disappear after a few milliseconds; it is transferred to your short-term memory or your working memory.

Your sensory memory is very useful in everyday life. It allows you to enjoy the movies you see at the theatre or on television. Movies are made up of a series of separate fixed images displayed very quickly (about 24 images per second). If you perceive continuous fluid motion in a movie, it is because each image is held briefly in your sensory memory before being replaced.