April 10, 2013
Assessing Ariel Sharon
On the night of Jan. 24, former Israeli Prime Minister Ariel Sharon was transported to Soroka University Medical Center in the southern Israeli city of Beersheba. Secured horizontally and face-up, he was passed slowly through an advanced magnetic resonance imaging (MRI) machine, which enabled UCLA psychology professor Martin Monti and a team of Israeli experts to perform an array of tests that lasted 90 minutes.
Sharon, now 85, suffered a massive stroke in early 2006 and has since been in a vegetative state. Soon after being hospitalized, the military hero and veteran politician was succeeded as premier by Ehud Olmert. Sharon has since been under round-the-clock care at Tel Hashomer Hospital near Ramat Gan.
At Soroka, he underwent tests, known as functional MRIs, which review various brain functions. The results were significant, because the appropriate parts of Sharon’s brain showed activation each time he was instructed, for example, to conjure images of his home and of playing tennis (an activity he once enjoyed). Sharon’s brain reaction also was monitored when he was shown photographs of himself during his military career and when the recorded voice of his son Gilad was played.
UCLA psychology professor Martin Monti. Photo courtesy of Martin Monti
Those activations, illustrated dramatically on a computer monitor when a spark appeared in images of the relevant portions of the brain, indicated Sharon’s having understood and executed each instruction, and together mean that Sharon can be classified as “minimally conscious,” according to interviews this month with three people who participated in the testing: Monti, whose specialty is patients in a vegetative state; Dr. Alon Friedman, the head of Ben-Gurion University’s (BGU) Zlotowski Center for Neuroscience; and Erez Freud, a doctoral student in BGU’s psychology department.
Sharon’s celebrity aside, the tests were noteworthy because of the patient’s advanced age and the seven years that had elapsed since his stroke, the three men explained.
However, the trio emphasized in separate interviews, the tests could not determine whether Sharon consciously had made those associations or, instead, had responded reflexively. And because so little is known about the brain activity of patients in a vegetative state who occupy Sharon’s demographic, many more such people would have to be examined for scientific conclusions to be drawn, they said.
Sharon’s reactions to the stimuli “didn’t indicate consciousness” but did show that “the neurons were responsive,” Freud said on a recent morning as he sat with a Journal reporter in the all-white examination room two stories below ground where the tests on Sharon were conducted. As he spoke, a male volunteer in a research project passed through the MRI machine and was being observed through windows by several technicians and students, much as Sharon had been six weeks earlier.
The MRI machine, manufactured by Philips, is the most advanced of its kind and was purchased by the American Associates of BGU for use by both the school and its hospital, which sit across the street from one another.
Each scan of Sharon took approximately seven minutes. The examination progressed from the simplest audio and visual stimuli to highly complex images of a male face and of a house overlaying one another, which Sharon was asked to distinguish. He was also given a somatosensory test, in which a nurse massaged Sharon’s hand and stopped, then resumed; yet another included film clips about Sharon, one a television spoof of him, all of which “would excite him and would be emotional” to see under normal circumstances, Friedman explained.
Dr. Alon Friedman and the MRI machine. Photo by Dani Machlis/Ben-Gurion University
“All the modalities were responsive: We got responses from the visual cortex, the auditory cortex and the somatosensory cortex,” Freud said. All told, the findings “were really surprising and really good … but, again, all these tasks are not indicative of [Sharon’s] consciousness,” Freud said. “There was faint activation in these [brain] locations. We saw some activation in areas devoted to face recognition when we told him to focus on the face. But it was faint. We are still analyzing the data.”
The tests demanded extensive preparation. Freud flew to Los Angeles several weeks beforehand to consult with Monti. Friedman, and later Monti, visited Sharon at Tel Hashomer a few days before the Soroka examination. The Tel Hashomer tests yielded very little response to such stimuli as loud noises and movements near Sharon’s eyes.
“That’s the problem with negative results: You don’t know what they mean,” Monti said. “There are so many reasons someone might not respond to a test. We don’t really know what consciousness is. There’s no thermometer we can stick in the ear [to know].”
All told, “I’m not sure I’ve made up my mind about what this all means,” Monti, speaking by Skype from Japan, where he was traveling, said of his work on Sharon. “We’re still in a gray area. … Honestly, it’s a case that’s been puzzling me since I saw him.”
More broadly, the experience fits into Monti’s research and academic work at UCLA by addressing core questions: What is the neurological fingerprint of consciousness? Why do some patients in a vegetative state recover, while others do not? What causes someone’s consciousness to disappear? And what, really, is consciousness?
Friedman, Monti and Freud all said that they hope to collaborate again to continue their research into elderly people in a vegetative state. The former prime minister, back at Tel Hashomer, is but one such patient, they said.
“This is just the beginning of the project,” said Friedman, a neurosurgeon turned researcher. “It’s pretty complex. It’s not easy at all.”