Any of a class of neurons found in the cortex of the brain of monkeys that fire not only when the monkey performs an action (e.g. picking up a banana) but also when the monkey sees or hears someone else performing the same action, i.e. a ‘reflection’ of the action. There is evidence that such neurons are also present in parts of the human cerebral cortex. It has been hypothesized that mirror neurons function in understanding the actions of others, and more broadly in various aspects of communication and socialization. According to some researchers, they may also play a significant role in the development of language, by enabling individuals to imitate gestures and sounds that are goal-oriented, i.e. are associated with a purpose or meaning.