MRI表明能意识到“微小的意识"(下)
They analyzed fMRI tests on two minimally conscious male patients, aged 22 and 33, both of whom had been unable to communicate consistently since their respective accidents.
During the experiment, the researchers played two audio tapes as the patients underwent fMRI scanning. In one tape, a friend or family member recited a short narrative of some kind. In the second audio test, the investigators simply ran the tape backwards--it was still recognizable as human speech, but became meaningless and garbled.
In an interview with Reuters Health, Hirsch and her colleague Dr. Nicholas Schiff report that areas of the brain known to be connected with the processing of speech showed high activity during the forward-playing storytelling, much as they would in healthy individuals.
However, this activity subsided when patients were exposed to the nonsense/backwards tape.
To the investigators, the findings appear to reflect the difference between "comprehension of the meaning in the narrative" on the one hand, and a mere "hearing" of meaningless sounds on the other.
In other words, the neurological tools necessary for the understanding of speech "appear to be operational" in these patients, the researchers said, suggesting that "certain brain functions are more preserved than previously imagined." But they stressed that the findings "do not indicate what level of understanding--or possible suffering--if any, is present."
More study is needed to get a better understanding of just how conscious the minimally conscious are. Still, Hirsch believes the findings give researchers a new "humanitarian imperative" to seek out therapies that could bring these patients some hope of recovery., 百拇医药
During the experiment, the researchers played two audio tapes as the patients underwent fMRI scanning. In one tape, a friend or family member recited a short narrative of some kind. In the second audio test, the investigators simply ran the tape backwards--it was still recognizable as human speech, but became meaningless and garbled.
In an interview with Reuters Health, Hirsch and her colleague Dr. Nicholas Schiff report that areas of the brain known to be connected with the processing of speech showed high activity during the forward-playing storytelling, much as they would in healthy individuals.
However, this activity subsided when patients were exposed to the nonsense/backwards tape.
To the investigators, the findings appear to reflect the difference between "comprehension of the meaning in the narrative" on the one hand, and a mere "hearing" of meaningless sounds on the other.
In other words, the neurological tools necessary for the understanding of speech "appear to be operational" in these patients, the researchers said, suggesting that "certain brain functions are more preserved than previously imagined." But they stressed that the findings "do not indicate what level of understanding--or possible suffering--if any, is present."
More study is needed to get a better understanding of just how conscious the minimally conscious are. Still, Hirsch believes the findings give researchers a new "humanitarian imperative" to seek out therapies that could bring these patients some hope of recovery., 百拇医药