According  to a spokesperson for Anne Heche, Anne Heche is now brain dead after  suffering injuries from a fiery car accident last Friday.

"Anne  is legally dead under California law. However, her heart still beats  and she has not been removed from life support so that One Legacy may  see if she's a match for organ donor," the spokesperson stated in a statement to NBC News

"Anne  is legally dead under California law. However, her heart still beats  and she has not been removed from life support so that One Legacy may  see if she's a match for organ donor," the spokesperson stated in a statement to NBC News

Heche's spokesperson stated in another statement Thursday that actress Heche was "not expected" to live after the August  5 car accident in which she sustained a "severe brain injury".

What is an Anoxic Brain Injury?  Anoxic brain injury occurs when there is a complete lack of oxygen in the brain, Andrea L. Schneider a neurologist at Penn Medicine,

and an assistant professor of neurology, at the Hospital of the University of Pennsylvania told Health.

Anoxic brain injury and hypoxic head injuries are two different things from traumatic brain injury, which is caused by a direct trauma such as a blow to a head.

Dr. Schneider explained that oxygen is essential for all cells of the body. Brain cells are dependent on a steady supply of oxygen from the blood

However, brain cells can suffer if this blood supply and oxygen is interrupted. Dr. Schneider added that brain cells can die if there is a shortage of oxygen

The  brain can feel the effects of oxygen deprivation quickly. Some brain  cells die in as little as five minutes. Brain damage can be rapid.

What causes an Anoxic Brain Injury (ABI)?  Dr. Schneider stated that anoxic brain injuries can be caused by any type of brain injury.

She explained that anoxic brain injuries are usually associated with someone's cardiac arrest. This is sometimes called a hypoxic ischemic injury.