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Ethical Issues in the Use of Human Brain Tissue for Therapeutic And J7ournal ofMedical Ethics 1998;24:118-122 J Med Ethics: first published as 10.1136/jme.24.2.118 on 1 April 1998. Downloaded from The brain-mind quiddity: ethical issues in the use ofhuman brain tissue for therapeutic and scientific purposes Larry Burd, Jennifer M Gregory and Jacob Kerbeshian University ofNorth Dakota, USA Abstract understanding the unique construct of brain The use ofhuman brain tissue in neuroscience activity which we call "the mind". This term, "the research is increasing. Recent developments include mind", is the conceptual vehicle used to commu- transplanting neural tissue, growing or maintaining nicate many of the brain activities which have yet neural tissue in laboratories and using surgically defied either anatomical or functional localization. removed tissuefor experimentation. Also, it is likely In some people with substantial amounts of miss- that in thefuture there will be attempts at partial or ing brain tissue all of these activities occur. Other complete brain transplants. A discussion of the ethical people with apparently normal brains demon- issues of using human brain tissuefor research and strate very few of these activities. Although the brain transplantation has been organized around role ofindividual parts ofthe brain remains poorly nine broadly defined topic areas. Criteria for human understood neuroscience seems posed to make use remarkable progress in the near future. A recent brain tissue transplantation and laboratory of copyright. brain tissue are proposed. development in clinical neuroscience has been the (Journal ofMedical Ethics 1998;24:118-122) isolation and laboratory growth ofbrain tissue cell Keywords: Brain transplantation; neuroscience; person- lines in laboratories around the world.4 These hood; life; ethics; brain; mind efforts at the cellular level and the whole brain or total body transplants in animals completed more than three decades ago by White and colleagues In a previous issue of the journal, Dr Gillon's edi- seem certain to be the focus of increasing empha-http://jme.bmj.com/ torial provided a framework and commentary as a sis from neuroscientists in the future. These companion piece to an article by Dr Northoff on strategies offer attractive methodologies for re- ethical issues of brain transplantation.' 2 These searchers and clinicians who seek to ameliorate articles provided an important first step for the sequelae of human central nervous system discussion of the philosophical and ethical issues disease and dysfunction."8 In contrast to the suc- surrounding brain transplantation. In this paper cess in animals of head transplants, the current we wish to add to this ongoing discussion and to science base suggests that mature cerebral tissue on September 24, 2021 by guest. Protected describe several additional relevant areas in this in large blocks cannot be homotransplanted into discussion. These issues relate to development of mature brains.7 8 These efforts at the cellular level the mind-brain duality, personhood, and self- on the one hand and at the level of whole brain identity. The 1990s have been designated as the transplants (limited to animals to date) on the "Decade of the Brain" to recognize both the other, give rise to nine important ethical, social, tremendous progress that has been made in the and scientific questions which are the focus of this basic and clinical neurosciences and to call atten- discussion: tion to the work yet to be done.3 Late into this decade important advances have revealed insights 1 Is it possible to grow brain tissue without the into the molecular basis of several neurological occurrence of corresponding mind (mental) disorders, for example, the diagnosis of Hunting- activities? ton's Chorea and Fragile X Syndrome. Impressive 2 If activity is present in this tissue, does it advances have accompanied these basic science support a mind-brain unit and as a result generate efforts in the understanding of functioning of the emotions, sensations, or other internally gener- central nervous system. Functional imaging stud- ated brain activity? ies have substantially enhanced the scientific 3 Should developmental experience be a criterion understanding of brain organization. However, for the brain-mind unit to have the qualities of a relatively little parallel progress has been made in person? Burd, Gregory, Kerbeshian 119 J Med Ethics: first published as 10.1136/jme.24.2.118 on 1 April 1998. Downloaded from 4 Might brain tissue separated from a body can be difficult to define and has been the subject of manifest fear, hopelessness, euphoria or creativity? numerous legal, moral, and ethical debates, this 5 Does the brain-mind unit need a body to have discussion looks the other way. At what level of the qualities of a person? brain activity is the mind functional? If the absence 6 If mental activities occur in laboratory brain ofthis activity defines brain death does the presence tissue specimens, how would these activities be of brain activity define life? The brain is a neural detectable? structure which develops very early in pregnancy, 7 If the mind-brain unit is present in laboratory and continues to develop throughout pregnancy brain tissue specimens should these laboratory and in the first years of life. The brain assumes specimens be used to study mental activities? control over a number of extremely important 8 Can a person give consent for his or her brain functions and becomes responsive to changes in the tissue to be grown or maintained in a laboratory environment very early in the developmental setting if the tissue had or later develops the inde- period. If removed from the head and maintained pendent capacity to respond at some level? would brain tissue have similar functional capaci- 9 Should a human subjects institutional review ties? Could this tissue support mental activities? In board review these activities and how could such a what way are the individual neurons grown in a board determine when a person is being studied culture different from the neurons that comprise rather than a collection of neurons? the brain of an airline pilot struggling to land a damaged plane, a first-grader walking home imag- ining the birthday presents he will receive tomor- 1) Is it possible to grow brain tissue without the row at his party, or of a physician walking into his occurrence of corresponding mind activities? office to tell one of his close friends that the friend There are several useful measures ofbrain activity has a fatal illness? Using the fictitious case of Susan and the absence of these are the most useful crite- referred to by Gillon,' questions 1) and 2) ask when ria for the diagnosis of brain death.9 The criteria does a collection of brain tissue become large for clinical death in use today refer to loss offunc- enough or have sufficiently organized neurophysi- copyright. tion of both the brain and the mind.'" Brain death ological activity to develop mental activities and results in a cessation ofthe brain-mind duality and become a "Susan". the loss ofpersonhood that makes possible the use 3) Should developmental experience be a crite- of all body parts for donation, experimental rion for the brain-mind unit to have the qualities dissection, or simply burial. Relatively little of a person? If a large number of neurons can be discussion has taken place about the maintenance grown in the laboratory setting and then develop http://jme.bmj.com/ or growth of brain tissue in laboratory settings. organized neural activity, could one argue that the Brain tissue grown in a laboratory dish is alive or lack of developmental experience prevents this dead. The "alive" state implies that the cells are at brain tissue from achieving mental activities? some level functional and responsive. The cells Would a lack of developmental experience pre- have metabolism and demonstrate some actions clude personhood status so that the tissue would similar to cells that are a part of the human brain always remain just tissue? Must brain tissue be when it is functional. It is obvious that whole attached to a body for developmental experience on September 24, 2021 by guest. Protected brains are not required for mental activity and to occur? psychological development to occur. Herein 4) Might brain tissue separated from a body resides the quiddity of the mind-brain relation- manifest mental experiences offear, hopelessness, ship. Are they, mind and brain, always biologically euphoria or creativity? The constructs used to and functionally linked? There is no evidence that describe or define many mind-brain activities are mental activity exists without brain tissue. But, poorly delineated but at their extremes easily rec- does living brain tissue always equate to mental ognized. The functional limitations of people with activity? From an ethical and philosophical view is profound mental retardation or the prodigious the relationship of brain -o neural activity -* capacity demonstrated by persons with savant mental activity (mind) always present. Or is the skills are easily recognized. People demonstrate a relationship trivial for small amounts of brain tis- wide range of responses to what appear to be vir- sue where the equation could be stated brain -e tually identical injuries. In the locked-in syndrome neural activity (neurochemical and electrical a person is unable to express himself while his organization).mental activity (mind)? brain has considerable functional capacity." This 2) If activity is present in brain tissue does it condition is surely amongst the most tragic of support a mind-brain unit and as a result generate those which afflict human beings. During general emotions, sensations or internally generated mental anaesthetic for surgery brain activity is markedly activity? While the boundary between life and death reduced but, because of the reversibility of this 120 The brain-mind quiddity J Med Ethics: first published as 10.1136/jme.24.2.118 on 1 April 1998.
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