As nouns the difference between brain and hypomyelination
is that
brain is the control center of the central nervous system of an animal located in the skull which is responsible for perception, cognition, attention, memory, emotion, and action while
hypomyelination is (medicine) an abnormally small amount of myelin in the brain and spinal cord.
As a verb brain
is to dash out the brains of; to kill by smashing the skull.