Functional magnetic resonance imaging (fMRI) of the activity in the brain of
former prime minister Ariel Sharon – who has lain in a deep vegetative state for
the last seven years – has been shown to be “surprisingly significant,”
according to a team of brain researchers at Beersheba’s Ben-Gurion University of
the Negev and Soroka University Medical Center on Sunday.
However, that
does not mean that he will ever regain consciousness, or that he feels anything,
other fMRI experts said.
The special scanner measures brain activity by
detecting changes in blood flow and is used to map neural activity in the brain
and the spinal cord. It does not require people to undergo shots, surgery,
ingest substances or be exposed to radiation.
The procedure is similar to
MRI, but uses the change in magnetization between oxygen- rich and oxygen-poor
blood as its basic measure.
The BGU-Soroka team said the results “show
the existence of sensory information processing” in Sharon’s brain, which
suffered severe damage as a result of his second stroke at Hadassah University
Medical Center in Jerusalem when he was prime minister.
The scan was
conducted on Thursday by BGU nerve scientist Prof. Alon Friedman and his
colleagues. Family friends made comments to Yediot Aharonot on Sunday about the
test.
Although the 85-year-old former prime minister has been taken care
of at Sheba Medical Center at Tel Hashomer – which has its own fMRI scanner –
for most of the time since he was felled by two strokes, he was brought by
ambulance to Beersheba for the tests.
Soroka said they were conducted
there because “advanced new imaging techniques” were recently made available to
the Beersheba hospital team by Prof. Martin Monti of the neurosurgery and
psychology departments at the University of California at Los Angeles. They
wanted to determine the “amount and quality of activity” in Sharon’s brain,
Soroka said.
During the two-hour test, researchers “showed” Sharon photos
of his family, played his son Gilad’s voice and presented stimulation by
touch.
To their surprise, Soroka said, “significant brain activity was
found in each test and in suitable brain areas. This demonstrates the existence
of sensory data processing” by his brain.
They then conducted some tests
aimed at estimating Sharon’s “level of consciousness,” and that despite the
existence of “several encouraging” results, “they were still too weak to reach
clear conclusions,” the team said.
Monti said that “information from the
external environment reaches suitable brain centers in Mr. Sharon’s brain.
Nevertheless, the evidence is not clear cut on how much he is aware of his
environment.”
Dr. Ilan Shelef, head of Soroka’s imaging center, said that
“this kind of research, which is at the forefront of science today, was the main
motivation for the purchase of the advanced fMRI by Soroka and BGU.”
Dr.
Tzvi Ganel, of BGU’s Zlotowski Center for Neuroscience, who initiated the tests,
said the Sharon family was pleased that the advanced techniques were used, and
they could be useful for other families.
BGU’s Dr. Galia Avidan added:
“This is the kind of research that opens a window on the understanding of basic
questions connected to deeper understand of the basis of human
consciousness.”
Soroka’s fMRI model is Philips’ 3T Ingenia.
“This
important test expressed the great effort and cooperation between BGU and
Soroka. There is no doubt that we wouldn’t have been able to reach the necessary
level of execution without it,” said Soroka imaging center director Dr. Ilan
Shelef.
BGU president Prof. Rivka Carmi said the cost of the device was
about $3 million, and it is “regarded as the most advanced of its kind in
Israel.” The cost was covered not only by Soroka and BGU but by Soroka owner
Clalit Health Services and US donors.
“The new system,” said Carmi,
“makes possible the immediate conversion of the analog signals that the body
releases to digital signals and greatly improves the quality of the picture and
the speed of the scanning compared to analog systems.”
Meanwhile,
researchers at other fMRI centers, who did not want to be quoted because they
have not examined Sharon nor seen his medical file, noted that they too have
studied reactions in patients who are in deep comas.
Patients who have
been in such a coma for a shorter period may come out of it, they said. Patients
without severe brain injuries could react through an fMRI scan, not if asked yes
or no questions, but if told to think of a specific object, or if they could
answer a particular question. A familiar piece of music or odor could also
trigger a reaction.
But reacting to stimuli via fMRI does not mean the
patient has awareness, they added, or that the patient really can
communicate.
However, brain research on patients in a deep vegetative
state could, they agreed, have the potential to help patients in the future, as
they could learn how to awaken patients. The actual chances of recovery for a
person who has been in a deep vegetative state for seven years is virtually nil,
they concluded.
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