The Moral Status and Welfare of Patients Diagnosed As Vegetative with Covert Awareness
Total Page:16
File Type:pdf, Size:1020Kb
Western University Scholarship@Western Electronic Thesis and Dissertation Repository 7-8-2016 12:00 AM The Moral Status and Welfare of Patients Diagnosed as Vegetative With Covert Awareness Mackenzie S. Graham The University of Western Ontario Supervisor Charles Weijer The University of Western Ontario Joint Supervisor Anthony Skelton The University of Western Ontario Graduate Program in Philosophy A thesis submitted in partial fulfillment of the equirr ements for the degree in Doctor of Philosophy © Mackenzie S. Graham 2016 Follow this and additional works at: https://ir.lib.uwo.ca/etd Part of the Ethics and Political Philosophy Commons Recommended Citation Graham, Mackenzie S., "The Moral Status and Welfare of Patients Diagnosed as Vegetative With Covert Awareness" (2016). Electronic Thesis and Dissertation Repository. 3859. https://ir.lib.uwo.ca/etd/3859 This Dissertation/Thesis is brought to you for free and open access by Scholarship@Western. It has been accepted for inclusion in Electronic Thesis and Dissertation Repository by an authorized administrator of Scholarship@Western. For more information, please contact [email protected]. i Abstract Several neuroimaging studies have demonstrated that a minority of patients diagnosed as being in the vegetative state are able to modulate their brain activity in response to the commands of researchers, thus demonstrating that they are ‘covertly aware.’ I examine the moral significance of this discovery, with a specific focus on the implications for patient welfare. I argue that the presence of awareness in these patients is important because it allows for the presence of sentience—the capacity for suffering and enjoyment—which I argue is a sufficient condition for moral status. Insofar as these patients have moral status, their interests matter morally; we have an obligation to give them proper consideration in our decision making. I present empirical evidence which supports the assumption that patients diagnosed as vegetative with covert awareness are sentient, and thus have moral status. I then consider an account of the welfare of these patients, which incorporates three traditional conceptions of welfare—hedonism, desire- satisfaction, and objective theories—and concludes that these patients are faring poorly, such that we may have a moral obligation to end their lives. I analyse and ultimately reject this conclusion. I argue that the application of traditional theories of welfare to these populations is impeded by a lack of knowledge of their subjective experiences, as well as challenges to the conceptions of welfare themselves. I then propose a novel approach for assessing the welfare of these patients, based on their subjective experiences. This approach involves extrapolating from the reported welfare interests of similar patient populations, as well as making plausible inferences about the residual cognitive capacities of these patients, based on the results of novel neuroimaging studies. Using these two sources of information, we can begin to construct a clearer picture of the welfare of these patients, and work to ensure that they have a decent quality of life. Keywords Welfare, neuroimaging, vegetative state, sentience, moral status, quality of life. ii Acknowledgments First and foremost, I would like to thank my thesis supervisor, Dr. Charles Weijer, for the unyielding support and encouragement he has provided to me since I began as his trainee. Dr. Weijer has been a true mentor to me, both as a philosopher and as a professional. He consistently pushed me to produce the best work that I could, while expressing a confidence in me that I did not always have in myself. He has been an exemplary supervisor, and it has been a privilege to work with him. I would also like to thank my co-supervisor Dr. Anthony Skelton, without whose expertise this project simply would not have been possible. I thank him for his insight, and for continually pressing me to think carefully about my arguments. Additionally, I would like to thank Dr. Eric Desjardins, the third member of my committee, as well as the other members of my defense committee: Dr. Gillian Barker, Dr. Ross Norman, and Dr. Dan Haybron. Your feedback on the thesis itself, as well as the lively discussion within the defense, will certainly help to shape my thinking on this project moving forward. A special thank you to the members of the interdisciplinary research group between Western’s Brain and Mind Institute, and the Rotman Institute of Philosophy: Andrew Peterson, Lorina Naci, Tommaso Bruni, Robert Foley, Davinia Fernandez-Espejo, Laura Gonzalez-Lara, Damian Cruse, Austin Horn, Bryan Young, Tenielle Gofton, Kathy Speechley, Jasmine Tung, Andrea Lazosky, Loretta Norton, and of course, Charles Weijer and Adrian Owen. Presentations made to this group, as well as the valuable feedback and discussion provided by many of its members, greatly contributed to this project. Finally, I would like to thank my parents Robert and Susan Graham, and my partner Siobhan Frank, for their emotional support over the course of this long journey. I hope that I have made you proud. And thanks to my faithful companion Frieda, who was by my side for nearly every one of the thousands of words that went into this thesis, and always ensured that I took regular breaks to walk. iii Table of Contents Abstract ............................................................................................................................................ i Acknowledgments .......................................................................................................................... ii Table of Contents .......................................................................................................................... iii Chapter 1: The Vegetative State, With Covert Awareness: A Unique Patient Population ..... 1 1.1 Introduction .............................................................................................................................. 1 1.2 The Vegetative State ................................................................................................................ 3 1.2.1 The Vegetative State: Prevalence ...................................................................................... 3 1.2.2 The Vegetative State: Causes and Recovery ..................................................................... 5 1.2.3 The Vegetative State: Symptoms and Assessment ............................................................. 6 1.2.4 The Vegetative State: Comparison to Coma, and Minimally Conscious State ................ 7 1.3 Operationalizing Consciousness in a Neurological Context ................................................. 8 1.4 Functional Neuroimaging in Vegetative Patients ................................................................ 13 1.5 Functional Neuroimaging in Vegetative Patients: The Mental Imagery Task ................. 17 1.6 The Discovery of Covert Awareness in Vegetative Patients: Ethical Issues ..................... 19 1.7 Patient Welfare and Patient Autonomy ............................................................................... 21 1.7.1 Challenges of an Autonomy-Centered Approach ........................................................... 23 1.7.2 Objections to a Focus on Patient Welfare ....................................................................... 26 1.7.3 The Need for a Welfare-Centered Approach .................................................................. 29 Chapter 2: Sentience and Moral Status ..................................................................................... 31 2.1 What is Moral Status? ........................................................................................................... 36 2.2 Who has Moral Status? ......................................................................................................... 38 2.3 Sentience and Moral Status: Historical Background ......................................................... 40 2.4 Sentience and the Capacity for Interests ............................................................................. 43 2.5 Group-Based and Individually-Based Accounts of Moral Status ...................................... 46 2.6 Indirect Duty Views ............................................................................................................... 49 2.7 Alternatives to the Sentience Criterion ................................................................................ 51 2.7.1 Sophisticated Cognitive Capacities .................................................................................. 52 2.7.2 Objections to Sophisticated Cognitive Capacity Views ................................................... 55 2.7.3 The Problem of Marginal Cases ...................................................................................... 57 2.7.4 Potential for Sophisticated Cognitive Capacities ............................................................ 61 iv 2.7.5 Objections to Potentiality Views ...................................................................................... 61 2.7.6 Ethical Egoism ................................................................................................................. 64 2.7.7 Objections to Ethical Egoism .......................................................................................... 67 2.8 Summary ................................................................................................................................