Emilia Clarke's 'Missing Brain' Parts And How She Can Function Without Them

At the start of this week, Emilia Clarke, Game of Thrones star, spoke about her "remarkable" recovery following two brain aneurysms and a subarachnoid hemorrhage—a stroke caused by bleeding inside the brain—that left parts of her brain "missing."

A brain aneurysm refers to an abnormal bulge or ballooning along the wall of an artery in the brain. Some brain aneurysms don't cause any problems, while others can rupture, leading to a hemorrhage—the spilling of blood into the surrounding tissue. In some cases, an aneurysm can cause a small amount of blood to leak into the brain.

In an interview with the BBC's Sunday Morning program on July 17, Clarke said: "The amount of my brain that is no longer usable—it's remarkable that I am able to speak, sometimes articulately, and live my life completely normally with absolutely no repercussions.

"There's quite a bit missing, which always makes me laugh. Because strokes, basically, as soon as any part of your brain doesn't get blood for a second, it's gone..."

So how is Clarke able to still go on living with parts of her brain missing?

How Does the Brain Work When Parts of It Are Gone?

Speaking to Newsweek, Dr. Andrew Russman, head of the stroke program at Cleveland Clinic in Ohio, said: "Plasticity represents the ability of the brain to adapt, and allows the uninjured brain to take on new functions or allows already injured brain tissue to compensate for areas of injury and improve functional recovery."

Russman, who also directs the hospital's comprehensive stroke center, explained that patients who suffer injury due to bleeding into the brain tissue, or who experience complications such as a vasospasm-induced stroke, "may have motor, sensory, visual, gait or language deficits."

Vasospasm causes the brain's arteries to contract and limit blood flow to vital parts of the brain, according to the National Institute of Neurological Disorders and Stroke.

Russman said: "Patients may improve after these types of deficits, through intensive rehabilitation, and the capacity of the brain to adapt to injury."

How Do Brain Aneurysms Impact the Rest of the Body?

Those who experience aneurysmal subarachnoid hemorrhage "may suffer various complications," said Russman.

Bleeding into the fluid-filled spaces of the brain may result in irritation of the blood vessels. This can lead to spasms and a loss of blood flow to the brain tissue, which deprives the area of the blood flow needed and results in a stroke or infarct, he said.

An infarction occurs from an inadequate supply of blood to brain cells. The lack of oxygen and vital nutrients can cause parts of the brain to die off.

Russman said a stroke or infarct may cause weakness, sensory loss, visual loss, language difficulty or trouble walking. Ruptured brain aneurysms may also cause convulsions or "may depress cardiac activity resulting in shock," the Cleveland Clinic medical director said.

Is There a Higher Risk for Brain Malfunction After an Aneurysm?

Russman said stroke, which includes bleeding-type strokes such as aneurysmal subarachnoid hemorrhage, is a leading cause of serious long-term disability in the U.S.

According to the medical director, up to 15 percent of patients with a ruptured brain aneurysm "do not survive to make it to the hospital."

In the U.S., "the median mortality rate" following a ruptured brain aneurysm is about 32 percent. Around 20 percent of those who survive a ruptured brain aneurysm are left with a long-term disability, he said.

The Mayo Clinic explains that an "aneurysm that has ruptured or leaked is at risk of bleeding again" and "re-bleeding can cause further damage to brain cells."

For more information, see the websites for the National Institute of Neurological Disorders and Stroke, the Brain Aneurysm Foundation, and the American Stroke Association.