Myelencephalon

The myelencephalon or afterbrain[1] is the most posterior region of the embryonic hindbrain, from which the medulla oblongata develops.

[2] Myelencephalon is from myel- (bone marrow or spinal cord) and encephalon (the vertebrate brain).

[3] During fetal development, divisions of the neural tube that give rise to the hindbrain (rhombencephalon) and the other primary vesicles (forebrain and midbrain) occur at 28 days after conception.

[4] Final shape differentiation of the myelencephalon into the medulla oblongata can be observed at 20 weeks gestation.

2) Cardiac & Vasomotor Center:[8] monitors and regulates cardiovascular activities by: 3) Reflexes Because of its location in the brainstem and its many important roles in the autonomic nervous system, damage to the medulla oblongata is usually fatal.

The embryonic brain develops complexity through enlargements of the neural tube called vesicles; (a) The primary vesicle stage has three regions, and (b) the secondary vesicle stage has five regions.
Primary and secondary vesicle stages of development [ 6 ]
Medulla oblongata- animation