What do the corticospinal tracts control?

The corticospinal system controls voluntary movement. It consists of the lateral corticospinal tract and the anterior corticospinal tract, which control distal musculature and proximal musculature, respectively.

The lateral corticospinal tract controls the digits of the hand. The axons in this tract are greater in number in humans and nonhuman primates than in other animals. It is thought that this is because these organisms exhibit manual dexterity that others do not.

Damage to this tract results in a loss of fine control in this area. Although other areas can assist in enabling the organism to perform coarser movements, they cannot assist in the finer movements the corticospinal tract enables.