1. Reticular formation
Reticular formation extends through the hindbrain, midbrain, and forebrain.
The reticular formation is a complex network of brainstem nuclei and neurons that serve as a major integration and relay center for many vital brain systems to coordinate functions necessary for survival.
The reticular formation is composed of a network of diffuse aggregations of neurons distributed throughout the central parts of the medulla, pons, and midbrain.