Lynne Turner-Stokes professor of rehabilitation, Jenny Kitzinger professor of communications research, Helen Gill-Thwaites consultant occupational therapist, E Diane Playford reader in neurological rehabilitation, Derick Wade professor of neurological rehabilitation, Judith Allanson consultant in neurorehabilitation et al
Turner-Stokes L, Kitzinger J, Gill-Thwaites H, Playford E D, Wade D, Allanson J et al.
fMRI for vegetative and minimally conscious states
BMJ 2012; 345 :e8045
doi:10.1136/bmj.e8045
Re: fMRI for vegetative and minimally conscious states
We are grateful for the positive comments contained about the Panorama special, 'The Mind Reader: Unlocking My Voice.'
As the article rightly says the programme "provided important insights into the devastating experience of patients who live in vegetative or minimally conscious states and the families who support them. It also provided useful information on the use of functional magnetic resonance imaging (fMRI) to explore evidence of localised brain activity that might indicate underlying awareness."
This was a ground-breaking documentary. The Royal Hospital for Neuro-disability in London had never before given filming access to patients undergoing SMART assessment. It was the first time that severely brain-injured patients have been filmed anywhere in the world undergoing fMRI as part of attempts to search for hidden consciousness.
The article suggests that the programme failed to "clearly distinguish" between patients who live in vegetative or minimally conscious states. It says: "Patients in a vegetative state have no discernible awareness of self and no cognitive interaction with their environment. Patients in a minimally conscious state show evidence of interaction through localising or discriminating behaviours, although such interactions occur inconsistently."
The script contained several explanations of these conditions, for example when referring to one patient undergoing assessment: "Staff here will try to assess whether he is minimally conscious with fragments of understanding or vegetative - with no awareness at all."
Based solely on viewing this one-hour documentary the authors felt able to discern that both the Canadian patients "said to be in a vegetative state" are "probably” minimally conscious.
One of these patients, Scott, has had the same Neurologist for more than a decade. Professor Bryan Young, who appeared in the film, made clear that Scott had always appeared vegetative in every assessment - including those done after his fMRI. The very fact that Scott’s fleeting movement, shown in the programme, was taken to indicate a purposeful (“minimally conscious”) response by these authors, illustrates why it is so important that the diagnosis is made in person, by an experienced Neurologist using internationally agreed criteria. In the programme, Professor Young stated that it was only Scott's cognitive responses in the fMRI scanner that had revealed covert awareness.
Indeed, Scott was able to respond in the scanner that he was not in any pain, which his parents felt was extremely valuable information. This was the first time that a patient in a vegetative state had been able to answer a question of clinical relevance while undergoing fMRI.
The programme did not say that the other Canadian patient, Steven, was vegetative. His parents explained on camera that he had a variety of means of physically responding, but that these were inconsistent. This fragmented ability to respond is indicative of the minimally conscious state. It should be remembered that this documentary was intended for a largely lay audience rather than a submission to a medical journal.
Nevertheless, Steven was also able to respond in the scanner and to show that he is aware that he has a niece, born three years after his brain injury. Irrespective of Steven’s formal diagnosis (minimally conscious or vegetative), his physical condition precluded any such questions being asked, or answered, until the moment he entered the scanner in Ontario – a moment that was captured for the first time in this film. Moreover, this was vital information for his parents, who wanted to know whether he was able to lay down new memories and to retain information. The documentary made clear that the level of the patients' cognitive abilities was unclear.
The authors also take issue with Professor Adrian Owen's assertion that nearly 20% of vegetative patients who he had scanned were capable of showing awareness as not being supported by the published evidence. Yet the only peer-reviewed evidence that is available to date clearly bears this out - including 4 out of 23 (17%) vegetative patients in a study published in the New England Journal of Medicine[1] in 2010. Indeed, in a later study published in The Lancet[2] and involving an independent group of patients, a related technology not featured in the programme (electroencephalography – EEG[3]) places this figure at even higher (19%).
References
1. Monti, M.M., Vanhaudenhuyse, A., Coleman, M.R., Boly, M., Pickard, J.D., Tshibanda, J-F.L., Owen, A.M. and Laureys, S. Willful modulation of brain activity and communication in disorders of consciousness. New England Journal of Medicine, 362, 579-589, 2010.
2. Cruse, D., Chennu, S., Chatelle, C., Bekinschtein, T.A., Fernandez-Espejo, D., Pickard, D.J., Laureys, S. and Owen, A.M. Bedside detection of awareness in the vegetative state. The Lancet, DOI:10.1016/S0140-6736(11)61224-5, 2011.
3. Cruse, D., Chennu, S., Fernandez-Espejo, D., Payne, W.L., Young, B. and Owen, A.M. Detecting Awareness in the Vegetative State: Electroencephalographic Evidence for Attempted Movements to Command. PLoS ONE 7(11): e49933. doi:10.1371/journal.pone.0049933
Fergus Walsh, Medical Correspondent BBC, United Kingdom
fergus.walsh@bbc.co.uk
Frank Simmonds, Deputy Editor Panorama, United Kingdom
frank.simmonds@bbc.co.uk
Prof. G. Bryan Young, Department of Clinical Neurological Sciences, University of Western Ontario, Canada
bryan.young@lhsc.on.ca
Prof. Adrian M. Owen, Canada Excellence Research Chair in Cognitive Neuroscience and Imaging, University of Western Ontario, Canada.
adrian.owen@uwo.ca
Competing interests: No competing interests