Monti, M. M., Vanhaudenhuyse, A., Coleman, M. R., Boly, M., Pickard, J. D., Tshibanda, L. et al. (2010). New England Journal of Medicine 362(7):579–589. doi:10.1056/NEJMoa0905370.
Key takeaways
From the reading, NOTE-964.
- Prevalence. 5 of 54 patients, 4 of 23 admitted as vegetative, could “willfully modulate their brain activity”; all five had traumatic injuries, and no patient with a non-traumatic injury responded.
- Undetectable at the bedside. Of the four admitted vegetative, two “remained behaviorally unresponsive at the bedside, even after the functional MRI results were known” (p. 585).
- The code. Tennis imagery for one answer, spatial navigation for the other, cued by the neutral word “answer”. Questions were chosen so “the investigators would not know the correct answers before judging the functional MRI data” (p. 581). Controls: 48 of 48 correct.
- Patient 23. Diagnosed vegetative at 17 months and 3.5 years, scanned at 5 years; on retesting, “reproducible, but inconsistent, responses indicative of a minimally conscious state”, but no bedside communication. Five of six questions answered correctly; the last gave no signal, and why “cannot be determined”.
- Unknown history. Whether he was aware at the earlier diagnoses is “indistinguishable” from later recovery, all earlier assessments being behavioural (p. 588).
Why this is here
For CASE-107: judgement shown, as correct yes/no answers to questions the investigators could not answer, through mental imagery with no action on the world in the channel that carried it. It is the strongest evidence the record holds of judgement running without action on the world, but not of judgement with every contingency removed: the patient who answered still had inconsistent voluntary motor responses, and the two with no bedside behaviour were not asked questions. The questions were about his life before the injury, so they test a model built while acting, not one kept in touch since. The channel is motor imagery read from the supplementary motor area (CLAIM-337’s action moved inward), and the case’s asymmetry shows twice: negatives in 49 patients and the silent sixth answer are uninterpretable.