What is brain-stem death?
This is where the lower part of the brain, called the brain-stem, is not functioning and has no chance of ever functioning again. The brain-stem has many crucial functions, including the reticular activating system, an area responsible for activating and deactivating the rest of the brain. As a result of brain-stem death, none of the brain (including the cortex) will show any external evidence of working. The brain-stem also controls breathing, so that a person whose brain-stem isn’t working cannot breathe at all on their own. He or she is unconscious and the beating heart is totally dependent on getting oxygen from a ventilator.
