The Brain Stem includes the Medulla
Oblongata, the Pons, and the Midbrain
The brain stem is usually defined to included the medulla oblongata, the pons, and the midbrain.
The medulla oblongata is the lower half of the brainstem. The medulla controls the cardiac and respiratory systems. It manages autonomic functions such as breathing, heart rate and blood pressure. It also controls reflex actions such as vomiting, coughing, sneezing, and swallowing.
The pons or pons varolii is located in the frontal part of the brain stem, below the midbrain and above the medulla oblongata. They are located in front of the cerebellum. The pons are responsible for relaying signals between the cerebrum and the cerebellum. They are involved in body functions such as sleep, respiration, swallowing, bladder control, hearing, equilibrium, taste, eye movement, facial expressions, facial sensation, and posture.
The midbrain is located at the posterior or back of the brain stem, above the cerebellum. The midbrain is involved in functions such as vision, hearing, eye movement, and body movement.