A couple of months ago, the BBC TV show Panorama covered the work of a team of neurologists (led by Prof. Adrian Owen) who are pioneering the use of fMRI scanning to measure brain activity in coma patients.
The startling claim is that some people who have been considered entirely unconscious for years, are actually able to understand speech and respond to requests - not by body movements, but purely on the level of brain activation.
However, not everyone was impressed. A group of doctors swiftly wrote a critical response, published in the British Medical Journal as fMRI for vegetative and minimally conscious states: A more balanced perspective
The Panorama programme... failed to distinguish clearly between vegetative vs. minimally conscious states, and gave the impression that 20% of patients in a vegetative state show cognitive responses on fMRI.
There are important differences between the two states. 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 behaviours...
The programme presented two patients said to be in a “vegetative state” who showed evidence of cognitive interaction on assessment using fMRI but the clinical methods used for the original diagnosis were not stated. In both cases, family members clearly reported that the patient made positive but inconsistent behavioural responses to questions... one of these patients was filmed responding to a question from his mother by raising his thumb and the other seemed to turn his head purposefully.
So Panorama stands accused of passing off patients who were really minimally conscious, as being in a vegetative state. To see signs of understanding on brain scans from the latter would be truly amazing because it would be the first evidence that they weren't, well, vegetative.
However if they were 'merely' minimally conscious patients, it's not as interesting, because we already knew they were capable of making responses.
have replied in a BMJ piece
of their own. Given that they're charged with misleading journalism and sloppy medicine, they're understandably a bit snarky:
Just by viewing this one hour documentary the authors felt able to discern that both the 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 Young, who appeared in the film, made it clear that Scott had appeared vegetative in every assessment...
The fact that these authors took Scott’s fleeting movement, shown in the programme, to indicate a purposeful (“minimally conscious”) response shows why it is so important that the diagnosis is made in person, by an experienced neurologist, using internationally agreed criteria.
In other words, they were vegetative, and the critics who said otherwise, on the basis of some TV footage, were being silly.
In other words...it's on.
Turner-Stokes L, Kitzinger J, Gill-Thwaites H, Playford ED, Wade D, Allanson J, Pickard J, & Royal College of Physicians' Prolonged Disorders of Consciousness Guidelines Development Group (2012). fMRI for vegetative and minimally conscious states. BMJ (Clinical research ed.), 345 PMID: 23190911
Walsh F, Simmonds F, Young GB, & Owen AM (2013). Panorama responds to editorial on fMRI for vegetative and minimally conscious states. BMJ (Clinical research ed.), 346 PMID: 23298817