Skip to main content

Sharon brain results not proof he'll wake up

By Elizabeth Landau, CNN
updated 7:48 PM EST, Mon January 28, 2013
  • It's not known how fMRI results relate to patient's recovery from a coma
  • There is a continuum between brain death and normal awareness
  • Most improvement in a patient in a coma occurs within one to two years

(CNN) -- When the body is totally inert, the brain can still be busy.

Even in a coma, brain imaging technology has shown, some people's brains show blood flow patterns that indicate something is going on inside their heads, although it's not necessarily indicative of awareness.

Doctors say they have observed "significant brain activity" in former Israeli Prime Minister Ariel Sharon. They are basing this statement on the results of experiments done with functional magnetic resonance imaging, or fMRI, showing that Sharon's brain behaves differently when he is presented with familiar sounds and pictures than with unfamiliar stimuli.

"It suggests the brain has the capability to react," said Dr. Fatta Nahab, neuroscientist at the University of Miami, who is not involved in Sharon's care. "What that means in terms of long-term outcomes is indeterminate."

Ariel Sharon has brain activity

FMRI lets scientists see changes in blood flow in the brain, which is associated with neuronal activity. It does not measure the actual activity, but can provide clues that some areas are still functional.

How such results should be interpreted, and if there's any connection to a potential recovery, is not known.

Doctors compared Sharon's brain responses when he viewed photos of random houses to when he was shown a photo of his own house. They observed a different response in the brain in conjunction with the familiar place than for the other images.

Sharon, 84, also showed distinct brain activity patterns when his family members spoke to him, compared to when their voices were distorted so they were no longer familiar and sounded like gibberish.

The brain response for a family member's voice was in "the correct location" for when a cognitively normal person hears familiar people speaking, said Dr. Ilan Shelef, head of Medical Imaging at Soroka University Medical Center, who was involved in the fMRI tests but is not Sharon's attending physician.

Such results suggest there may be some higher processing of information going on, and that areas of the brain important for processing complex stimuli are still functioning, said Dr. Keith L. Black, chairman and professor in the department of neurosurgery at Cedars-Sinai Medical Center, who is not involved in Sharon's care.

It is not proof that Sharon is conscious of the familiar sounds and images, and recognizing them as a fully healthy person would, he said.

Because doctors had not given these tests to Sharon previously, it's unclear whether this represents an improvement.

CNN has reported since 2006 that Sharon has been in a coma since suffering a massive stroke that year. The longer a person is in a coma, the less likely he or she is to recover, Nahab said.

Shelef said that Sharon is not in a coma or vegetative state, and is somewhere between a coma and consciousness. He sleeps, wakes up, eats and swallows on his own, and his eyes open and close, Shelef said. Shelef declined to comment on Sharon's general health.

There is a continuum between brain death and normal awareness that patients such as Sharon fall into, Black said. The fMRI results suggest he is not brain dead, because areas above the brain stem are showing activity. There are also patients who are "locked-in," and are totally aware of the sights and sounds around them, but cannot move or speak.

Brain-controlled devices may help paralyzed people

For clinical purposes, it appears that Sharon is in a coma, Black said.

"We have seen patients make remarkable improvements after being in a coma for a long time, but the best prognostic indicator is how one does over time," Black said. "Most improvement will occur within the first one to two years."

As Sharon has been in a coma for seven years, the fMRI evidence is positive, but it would be unusual for him to start talking, for example, given how long he has stayed in this state, Black said.

The scientists have likely gotten these new results because, even when a person is in a coma, "parts of the nervous system that are still functioning are capable of learning and capable of changing their activity patterns," said Dr. Daniel Hanley, professor of neurology, neurosurgery and anesthesia at the Johns Hopkins University School of Medicine, who is not involved with Sharon's care.

It's a phenomenon that has been studied and described before, he said.

"Even with severe brain injury, some qualities of the human existence are preserved and we should always treat patients with dignity," Hanley said.

But it's unclear what such brain activity patterns would mean for a patient's future. "We don't understand how these small changes in function are linked to recovery," he said.

If the same fMRI tests are repeated six months and nine months from now to compare activity levels, that would provide some indication of whether Sharon is headed in a positive direction, Black said.

"What you really want to know: Is he improving, and can you extrapolate that improvement out over some period of time to predict how well he's going to ultimately improve to?" he said.

Comatose Sharon moves home for weekend

CNN's Elizabeth Cohen and William Hudson contributed to this report.

Part of complete coverage on
updated 10:26 AM EST, Wed February 6, 2013
Advocates say the exam includes unnecessarily invasive and irrelevant procedures -- like a so-called "two finger" test.
updated 7:09 PM EST, Tue February 5, 2013
Supplies of food, clothing and fuel are running short in Damascus and people are going hungry as the civil war drags on.
updated 1:01 PM EST, Wed February 6, 2013
Supporters of Richard III want a reconstruction of his head to bring a human aspect to a leader portrayed as a murderous villain.
updated 10:48 AM EST, Tue February 5, 2013
Robert Fowler spent 130 days held hostage by the same al Qaeda group that was behind the Algeria massacre. He shares his experience.
updated 12:07 AM EST, Wed February 6, 2013
As "We are the World" plays, a video shows what looks like a nuclear attack on the U.S. Jim Clancy reports on a bizarre video from North Korea.
The relationship is, once again, cold enough to make Obama's much-trumpeted "reset" in Russian-U.S. relations seem thoroughly off the rails.
Ten years on, what do you think the Iraq war has changed in you, and in your country? Send us your thoughts and experiences.
updated 7:15 AM EST, Tue February 5, 2013
Musician Daniela Mercury has sold more than 12 million albums worldwide over a career span of nearly 30 years.
Photojournalist Alison Wright travelled the world to capture its many faces in her latest book, "Face to Face: Portraits of the Human Spirit."
updated 7:06 PM EST, Tue February 5, 2013
Europol claims 380 soccer matches, including top level ones, were fixed - as the scandal widens, CNN's Dan Rivers looks at how it's done.
updated 7:37 AM EST, Wed February 6, 2013
That galaxy far, far away is apparently bigger than first thought. The "Star Wars" franchise will get two spinoff movies, Disney announced.
updated 7:27 PM EDT, Fri July 25, 2014
It's an essential part of any trip, an activity we all take part in. Yet almost none of us are any good at it. Souvenir buying is too often an obligatory slog.