News of the Day ... In Perspective10/18/2006
More hope for patients in unresponsive states: three cases
A 38-year-old man, who had been barely conscious for six years after an assault, uttered coherent words and is regaining the use of his left arm since surgery to implant two electrodes deep in his brain.
The case could revive interest in electrical stimulation for the 100,000 to 200,000 Americans existing in states of partial consciousness.
James L. Bernat, M.D., a professor of neurology at Dartmouth Medical School, said he did not expect the treatment to help brain-damaged patients who had been totally unresponsive for more than a year. The patient in the report had intermittently been able to answer questions or follow commands by moving his left thumb or nodding. Imaging tests had shown that language circuits in the prefrontal cortex were preserved.
A pacemaker-like device was used to deliver electrical stimuli into the patient’s thalamus. A research team found consistent improvement in verbal and behavioral responsiveness when the device was turned on, but not while it was turned off.
The lead author of the study, Dr. Nicholas D. Schiff, thought that the patient could become more independent in chewing and swallowing and need less help to eat.
Consent for surgery was given by a family member with the proper legal authorization. Bioethicists expressed concern about preserving patients’ rights to refuse treatment (Benedict Carey, NY Times 10/16/06).
Earlier this month, the Associated Press reported the awakening of an 11-year-old boy who had been in a persistent vegetative state and required artificial ventilation for about two years after a mysterious illness (LifeNews.com 10/11/06).
Last month, researchers reported that a 23-old-woman who had shown all the signs of a persistent vegetative state after a car crash in July 2005 could perform mental tasks on request. Functional MRI showed patterns of brain activation strikingly similar to those of normal volunteers when the patient was asked to imagine herself playing tennis or walking around the house.
Chief investigator Adrian Owen said it was impossible to say whether the patient was fully conscious. “We can’t get inside her head and see what the quality of her experience is like” (Nature 2006(Sep 14);443:132-133).
Editorialist Michael Hopkin noted that this patient “seems to have been much less severely injured than the permanently vegetative Terri Schiavo.” But the research “raises questions about whether the definition of a vegetative state should be changed to allow the possibility of using brain imaging to ascertain awareness” (ibid.).
This case “raises the intriguing (or disturbing) possibility that there is a fully conscious being locked in that unresponsive body after all” (Wall St J 9/8/06).
Although certain aspects of cognition can go on in the absence of conscious awareness, Owen et al. write that “her decision to cooperate with the authors by imaging particular tasks when asked to do so represents a clear act of intention, which confirmed beyond any doubt that she was consciously aware of herself and her surroundings” (Science 2006(Sep 8);313:1402).