Activity-dependent plasticity

Activity-dependent plasticity is a form of functional and structural neuroplasticity that arises from the use of cognitive functions and personal experience; hence, it is the biological basis for learning and the formation of new memories. Activity-dependent plasticity is a form of neuroplasticity that arises from intrinsic or endogenous activity, as opposed to forms of neuroplasticity that arise from extrinsic or exogenous factors, such as electrical brain stimulation- or drug-induced neuroplasticity. The brain's 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 associated with neural plasticity and therefore many of the functions individuals perform on a daily basis. This plasticity occurs as a result of changes in gene expression which are triggered by signaling cascades that are activated by various signaling molecules (e.g., calcium, dopamine, and glutamate) during increased neuronal activity.

The brain’s ability to adapt toward active functions allows humans to specialize in specific processes based on relative use and activity. For example, a right-handed person may perform any movement poorly with his/her left hand but continuous practice with the less dominant hand can cause one to become ambidextrous. Another example is if someone was born with a neurological disorder such as autism or had a stroke that resulted in a disorder, then they are capable of retrieving much of their lost function through practice, which in turn "rewires" the brain to mitigate neurological dysfunction.

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