Wallerian degeneration

n. The disintegration of a nerve fiber after destruction of an axon segment downstream away from the cell body. The muscles or other cells innervated by the destroyed axon typically atrophy. Axons sometimes grow back after such destruction, with regrowth depending on the extent of damage and the distance between the cell body and the enervated tissue. In research, degeneration is sometimes brought about intentionally in order to track the path of an axon.