Reticulospinal tract

The reticulospinal tract (or anterior reticulospinal tract) is an extrapyramidal motor tract which travels from the reticular formation.

The sensory tract conveying information in the opposite direction is known as the "spinoreticular tract".

The tract is divided into two parts, the medial (or pontine) and lateral (or medullary) reticulospinal tracts (MRST and LRST). The MRST is caudal to the Superior Colliculus and is responsible for extensor muscles. The fibers of this tract arise from the caudal pontine reticular nucleus and the oral pontine reticular nucleus and project to the lamina VII and lamina VIII of the spinal cord (BrainInfo)

The LRST is rostral to the Superior Colliculus and is responsible for the flexor muscles. The fibers of this tract arise from the medullary reticular formation, mostly from the gigantocellular nucleus, and descend the length of the spinal cord in the anterior part of the lateral column. The tract terminates in the gray spinal laminae (BrainInfo).

If the Superior Colliculus is damaged, it is called decerebration and causes decerebate rigidity.