Patient outcome after serious brain injury is highly variable. Following a period of coma, some patients recover while others progress into a vegetative state (unresponsive wakefulness syndrome) or minimally conscious state. In both cases, assessment is difficult and misdiagnosis may be as high as 43%. Recent advances in neuroimaging suggest a solution. Both functional magnetic resonance imaging and electroencephalography have been used to detect residual cognitive function in vegetative and minimally conscious patients. Neuroimaging may improve diagnosis and prognostication. These techniques (...) are beginning to be applied to comatose patients soon after injury. Evidence of preserved cognitive function may predict recovery, and this information would help families and health providers. Complex ethical issues arise due to the vulnerability of patients and families, difficulties interpreting negative results, restriction of communication to “yes” or “no” answers, and cost. We seek to investigate ethical issues in the use of neuroimaging in behaviorally nonresponsive patients who have suffered serious brain injury. The objectives of this research are to: (1) create an approach to capacity assessment using neuroimaging; (2) develop an ethics of welfare framework to guide considerations of quality of life; (3) explore the impact of neuroimaging on families; and, (4) analyze the ethics of the use of neuroimaging in comatose patients. (shrink)

Consciousness in experimental subjects is typically inferred from reports and other forms of voluntary behaviour. A wealth of everyday experience confirms that healthy subjects do not ordinarily behave in these ways unless they are conscious. Investigation of consciousness in vegetative state patients has been based on the search for neural evidence that such broad functional capacities are preserved in some vegetative state patients. We call this the standard approach. To date, the results of the standard approach have suggested that some (...) vegetative state patients might indeed be conscious, although they fall short of being demonstrative. The fact that some vegetative state patients show evidence of consciousness according to the standard approach is remarkable, for the standard approach to consciousness is rather conservative, and leaves open the pressing question of how to ascertain whether patients who fail such tests are conscious or not. We argue for a cluster-based ‘natural kind’ methodology that is adequate to that task, both as a replacement for the approach that currently informs research into the presence or absence of consciousness in vegetative state patients and as a methodology for the science of consciousness more generally. 1. Introduction2. The Vegetative State3. The Standard Approach4. The Natural Kind Methodology5. Is Consciousness a Special Case? 5.1 Is consciousness a natural kind?5.2 A special obstacle?6. Conclusion. (shrink)

Patients in a Minimally Conscious State (MCS) constitute a subgroup of awareness impaired patients who show minimal signs of awareness as opposed to patients in a Vegetative State who do not exhibit any such signs. While the empirical literature is rich in studies investigating either overt or covert signs of awareness in such patients the question of self-awareness has only scarcely been addressed. Even in the occasion where self-awareness is concerned, it is only higher-order or reflective self-awareness that is the (...) target of such investigations. In the first part of this paper, I briefly review the relevant clinical neuroscience literature to demonstrate that the conception of self-awareness at play in such studies is indeed that of reflective self-awareness. In the second part, I present the philosophical notion of pre-reflective (or minimal) self-awareness. This is shown to primarily refer to the implicit awareness of our embodied subjectivity which essentially permeates all our experiences. As discussed, this minimal self-awareness is not specifically addressed when clinically or experimentally assessing patients in MCS. My suggestion is that neuroimaging studies targeting minimal self-awareness as in First-Person Perspective-taking paradigms could be used with MCS patients to shed light on the question of whether those individuals are minimally self-aware even in the case where they lack self-reflective abilities. Empirical evidence of this kind could have important theoretical implications for the discussion about the notion of self-awareness but also potential medical and social/legal implications for awareness impaired patients’ management. (shrink)

Disorders of consciousness pose a substantial ethical challenge to clinical decision making, especially regarding the use of life-sustaining medical treatment. For these decisions it is paramount to know whether the patient is aware or not. Recent brain research has been striving to assess awareness by using mainly functional magnetic resonance imaging. We review the neuroscientific evidence and summarize the potential and problems of the different approaches to prove awareness. Finally, we formulate the crucial ethical questions and outline the different articles (...) in this special issue on disorders of consciousness. (shrink)

In a recent study of a patient in a persistent vegetative state, [Owen, A. M., Coleman, M. R., Boly, M., Davis, M. H., Laureys, S., & Pickard, J. D. . Detecting awareness in the vegetative state. Science, 313, 1402] claimed that they had demonstrated the presence of consciousness in this patient. This bold conclusion was based on the isomorphy between brain activity in this patient and a set of conscious control subjects, obtained in various imagery tasks. However, establishing consciousness in (...) unresponsive patients is fraught with methodological and conceptual difficulties. The aim of this paper is to demonstrate that the current debate surrounding consciousness in VS patients has parallels in the artificial intelligence debate as to whether machines can think. Basically, used a method analogous to the Turing test to reveal the presence of consciousness, whereas their adversaries adopted a line of reasoning akin to Searle’s Chinese room argument. Highlighting the correspondence between these two debates can help to clarify the issues surrounding consciousness in non-communicative agents. (shrink)

Until comparatively recently, say the middle of the last century, spinal cord injury was fatal as pressure sores and other infections took their toll. Those with severe brain injuries, unable to move or even communicate, fared even worse; without movement or feeding such patients were nursed until nature took its course. Over the last few decades medical and nursing advances have enabled some of these vegetative patients to survive for considerable time, provoking, at times, ethical and legal dilemmas. Though they (...) survived, without overt behaviour or clear communication their carers were frequently unsure how much residual function remained. Now real progress is occurring in this area thanks to the application of neuro-scientific methods by some outstanding groups of workers. Subjects with severe brain injury may begin in complete, unresponsive coma but then ‘lighten’ to one of three categories. In vegetative state (VS), patients are apparently awake but without evidence of voluntary behaviour and have no apparent awareness of self or environment, whilst in minimally conscious state (MCS) patients have some behaviour beyond the reflex but are not able to communicate effectively. These conditions usually result from widespread brain damage at either or both cortical and subcortical levels due to injury or anoxia, though they can also be seen in end stage neurological conditions like Alzheimer’s. In locked in syndrome (LIS), patients ‘awake’ from coma, usually due to stroke, aware of their surroundings and their situation but unable to speak or move, beyond eye lid control and eye movement. For many, LIS will be recognised from Bauby’s extraordinary account in ‘The Diving Bell and the Butterfly,’ though, incidentally, it was presaged in Samuel Beckett’s novella ‘The Unnameable.’ LIS reflects a profound disconnection between brain and body, except for the upper cranial nerves involved in eyelid movement. The overriding question is how much awareness these patients have.. (shrink)

Severe brain injury is a leading cause of death and disability. Following severe brain injury diagnosis is difficult and errors frequently occur. Recent findings in clinical neuroscience may offer a solution. Neuroimaging has been used to detect preserved cognitive function and awareness in some patients clinically diagnosed as being in a vegetative state. Remarkably, neuroimaging has also been used to communicate with some vegetative patients through a series of yes/no questions. Some have speculated that, one day, this method may allow (...) severely brain-injured patients to make medical decisions. Yet, skepticism is rife, due in part to the inherent difficulty of assessing decision-making capacity through neuroimaging communication. In this thesis, I provide the first systematic analysis of this problem. I present and defend a strategy for assessing decision-making capacity in brain-injured patients who can only communicate through neuroimaging. (shrink)

Badania przy użyciu rezonansu magnetycznego sugerują, że przynajmniej niektórzy pacjenci w tzw. stanie wegetatywnym mogą być bardziej „świadomi”, niż to się do tej pory wydawało. W artykule zamierzam omówić te badania; następnie rozważę, o jakie rozumienie pojęcia świadomości może w nich chodzić; a wreszcie zastanowię się nad etycznymi implikacjami tych odkryć. Zamierzam też rozważyć, czy posiadanie wyższych form świadomości zawsze ma być dodatkową racją przemawiającą przeciwko zaprzestaniu podtrzymywaniu funkcji życiowych. Tym samym, w artykule chciałbym wskazać istotność badań z zakresu kognitywistyki (...) dotyczących pojęcia świadomości dla etycznej oceny pewnych praktyk medycznych. (shrink)