Following pioneering brain stimulation treatment, and after six years in a near vegetative state, a man is talking again, can feed himself, and has told his mother “I love you Mommy”.
The 38 year old American man was in a minimally conscious state following a horrific assault in 1999 where his skull was crushed and he was left for dead. His dramatic recovery came after doctors stimulated deep parts of his brain with electrodes. However, the doctors wished to warn families of other brain trauma patients not to expect the treatment to work on everyone.
A report on the treatment and results is published in the early online edition of the journal Nature and is accompanied by a short news piece.
The man, who cannot be named, has been in a minimally conscious state since his attack, confined to a bed in a nursing home. He could not swallow or speak and rarely opened his eyes, although he was mouthing words and making some attempts to communicate and respond. Brain scans showed that parts of his brain were intact and active.
Recent research has revealed the remarkable finding that some large scale networks in the brains of patients in the minimally conscious state (MCS) are still preserved and active. Signs of being aware of their environment or themselves are sometimes spotted in such patients.
After receiving the experimental, pioneering treatment, the American man can now speak, recognize and talk to people like family members and his carers, and do basic things like feed himself and brush his hair.
When the treatment was first proposed doctors told the man’s parents it was unlikely he would pull through, the outcome was so uncertain and unfortunately for many patients deep brain stimulation does not work. His mother told the press that her son can now say “I love you Mommy”. She said “God bless those wonderful doctors who believed in my son, and gave their time and effort to help my son.” She said her son now enjoys a quality of life they had never thought possible.
The case is reported in Nature as a single subject study of deep brain stimulation of the thalamus of a patient who has been in a minimally conscious state as a result of brain injury for six years.
The team that worked on the case included Nicholas Schiff from New York’s Weill Cornell Medical College, and first author of the study.
Their hypothesis was that a patient with MCS does not recover because large scale networks that are still active in the brain are not being stimulated.
Their plan was to provide this stimulation in a method called “bilateral deep brain electrical stimulation (DBS)”.
During a surgical operation the doctors implanted the electrodes in the thalamus. They activated them two days later and found the man kept his eyes open for longer than before and he responded to hearing someone speak by turning his head.
For the next six months they stimulated his brain a little more each day and eventually he regained the ability to chew his food and swallow it, and also to talk a little.
The man was still able to perform the improvements when the electrodes were not stimulating his brain, in the periods in between stimulation sessions, but the authors note that the frequency of the improved behaviours was greater during periods in which DBS was on as opposed to off.
Because the man was also still receiving rehabilitation therapy, the authors could not say for certain if the DBS had caused the improvement, but using logistic regression modelling, they were able to show there was a statistically signicant difference between the stimulation effects and the non stimulation effects on the man’s observed behaviour.
They said their findings showed that DBS can “promote significant late functional recovery from severe traumatic brain injury“.
The authors suggested that perhaps the DBS is compensating for the loss of an arousal function that is normally controlled by the frontal lobe in an uninjured brain.
They concluded that:
“Our observations, years after the injury occurred, challenge the existing practice of early treatment discontinuation for patients with only inconsistent interactive behaviours and motivate further research to develop therapeutic interventions.”
However, Schiff and colleagues pointed out that these results may not be achieved with other patients with similar brain injuries. The outcomes are not predictable and they called for further research on DBS for patients with severe brain injury.
“Behavioural improvements with thalamic stimulation after severe traumatic brain injury.”
N. D. Schiff, J. T. Giacino, K. Kalmar, J. D. Victor, K. Baker, M. Gerber, B. Fritz, B. Eisenberg, J. O’Connor, E. J. Kobylarz, S. Farris, A. Machado, C. McCagg, F. Plum, J. J. Fins and A. R. Rezai.
Nature 448, 600-603 (2 August 2007)
Published Online 1 August 2007.
“Implant boosts activity in injured brain.”
Nature 448, 522 (2 August 2007)
Published Online 1 August 2007.
Written by: Catharine Paddock