Brain injuries such as the one Schumacher encountered come in two types.
As WebMD states, individuals can suffer either a traumatic brain injury or an acquired brain injury and both disrupt the brain’s normal functioning.
Traumatic brain injury (TBI) – This is caused by an external force such as a blow to the head that causes the brain to move inside the skull or causes damage to the skull which in turn damages the brain.
Acquired brain injury (ABI) – This occurs at the cellular level and is most likely caused by some form of pressure on the brain. This could be caused by a tumour or neurological illness like a stroke.