High Quality Content by WIKIPEDIA articles! A defining feature of the brain is its capacity to undergo changes based on activity-dependent functions, also called activity-dependent plasticity. Its ability to remodel itself forms the basis of the brain’s capacity to retain memories, improve motor function, and enhance comprehension and speech amongst other things. It is this trait to retain and form memories that is functionally linked to plasticity and therefore many of the functions individuals perform on a daily basis. This plasticity is the result of changed gene expression that occurs because of organized cellular mechanisms.