Three varieties, distinguished by their color and representing different stages of the disease progress, are known respectively as red, yellow, and white softening.

[1][2] Ischemia: A decrease or restriction of circulating blood flow to a region of the brain which deprives neurons of the necessary substrates (primarily glucose); represents 80% of all strokes.

Hemorrhaging can occur in instances of embolic ischemia, in which the previously obstructed region spontaneously restores blood flow.

[1] Upon autopsy of several subjects, Dr. Cornelio Fazio found that the most common areas of this type of softening occurred where there was a hemorrhage of the middle cerebral artery or the superior or deep branches to it.

[2] Newborn cerebral softening has traditionally been attributed to trauma at birth and its effect on brain tissue into adulthood.

[7] However, more recent research shows that cerebral softening in newborns and the degeneration of white matter is caused by asphyxia and/or later infection.

There is no causal evidence to support the hypothesis that problems in labor contribute to the development of softening in infant white matter.

The identifiable softening enabled researchers to detect and partition cerebral areas related to different sensory perceptions.

[11] Another case in the late 19th century showed that cerebral softening, when caused by hemorrhaging, can affect various neural pathways leading to convulsions, spasms, coma and death.

Later she developed a yellow jaundiced appearance in the sclera and skin that the doctor proposed as paroxysmal hemoglobinuria upon autopsy.