An earworm or brainworm, also described as sticky music or stuck song syndrome, is a catchy or memorable piece of music or saying that continuously occupies a person's mind even after it is no longer being played or spoken about. Involuntary Musical Imagery (INMI) is most common after earworms, but INMI as a label is not solely restricted to earworms; musical hallucinations also fall into this category, although they are not the same thing. Earworms are considered to be a common type of involuntary cognition. Some of the phrases often used to describe earworms include "musical imagery repetition" and "involuntary musical imagery".