The Medulla Oblongata comprises the lower part of the brainstem (the upper part is called the Pons), and contains, among other things, the centers for respiration, cardiac function, and vomiting (yes, there really is a vomiting center).
Other autonomic (involuntary) reflexes such as heart rate, blood pressure, coughing, swallowing, gagging, and sneezing also reside here, making this a completely necessary structure for life.
Sounds crazy, but without the Medulla, we would not survive sleep since we wouldn’t remember to breathe, or keep our hearts beating, and in fact these are among the reflexes neurologists test for when establishing brain death.
– David Martin, VeinInnovations