We are at the moment confronted with yet another case of apparent “wakening” from Persistent Vegetative State (PVS), prompting one commentator to claim that “We will have to re-write the medical textbooks” (for story, see here). I would like to suggest that it might be better to recommend reading the medical textbooks first. PVS is often diagnosed when people show unresponsiveness after a head injury or severe stroke but it should only be confirmed as the diagnosis when neuro-imaging shows that there is extensive and persisting damage to most of the cortex, the highest level of cerebral evolution. This area of the brain contains many of and participates in all of the intricate connections concerned with intelligent communication and consciousness. A philosophical analysis of consciousness reveals why that is so and why the destruction of this extensive and sensitive layer of cerebral processing eliminates the many interwoven capacities that go to make up evolved consciousness. The fact that there are a number of capacities that contribute to the holistic function that is consciousness, as was realised by John Hughlings-Jackson, the father of British neurology, in the 19thcentury means that elements of conscious awareness can survive quite devastating brain injuries and lead to a patient who could respond, if the channels of communication were explored, may be dismissed as unconscious. This happens most dramatically with Locked in Syndrome as discussed in “Nick’s Story” published in the BMJ in 2005. There is a spectrum of disorders ranging from: Locked in Syndrome, where consciousness and intellect are intact but the pathways allowing communication with the outside world are virtually destroyed; through Minimally Conscious States, which are poorly described because there is a spectrum involved; to Persistent Vegetative State, where the neural substrate of intellect and consciousness is destroyed. Only when the neuropathology (as revealed by imagery), the clinical assessment, and the ethical sensitivity to the patient’s (and loved ones’) attempts to communicate are properly synthesized into a clear understanding of the patient’s condition can the relevant distinctions be made in practice.
Scott Routley is an example of that process being incomplete such that an ongoing harm is perpetrated against the patient and those who love him or her. The cases are varied and include akinetic mutism from brain damage or severe depression (often seen in the elderly), catatonic schizophrenia (I saw a dramatic case in an Afro-Caribbean young man in London), Locked in Syndrome (I have personally attended several), and in each case we should be sure we have read the texts (such as Plum and Posner’s classic The Diagnosis of Stupor and Coma) before we start re-writing them with the kind of half-baked insights that those who are ill-informed (on the neuroscience, pathology, neuro-imaging, clinical acumen, or ethics) littered throughout their (re-written) pages.
The Otago Bioethics Centre offers a course in Neuroethics for those who want to explore these issues further and a number of distinguished academic visitors prominent in the subject have made valuable contributions to that course. The course does however require that you read the material prescribed before venturing opinions on the difficult issues discussed.