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The modern analysis of flowers and flowering rests on description and interpretation of plant form. Chief among these is Goethe's foliar theory, which proposes that all aerial plant organs are analogous to a single organ. The foliar theory has underpinned all work on flower development, including modern molecular genetic analyses, as well as providing a frame of reference for evolutionary studies. This chapter describes Goethe's theory with reference to the flower, and its use and expansion by 20th-century botanists. An analysis of the differences and similarities between vegetative and floral organs is presented, which provides a framework for a section that interprets the foliar theory in an evolutionary context. The second half of the chapter moves on to consider historical interpretations of the transition from the vegetative state to the flowering state, describing the mechanisms proposed by early plant physiologists to explain this transition.

In recent years, rapid technological developments in the field of neuroimaging have provided new methods for revealing thoughts, actions and intentions based solely on the pattern of activity that is observed in the brain. In specialized centres, these methods are now being employed routinely in the assessment of patients diagnosed with so-called ‘disorders of consciousness’, mapping patterns of residual function and dysfunction and helping to reduce diagnostic errors between related conditions such as the vegetative and minimally conscious states. In some cases, functional neuroimaging has even been used to detect covert awareness in behaviourally non-responsive patients when standard clinical techniques have been unable to provide that information. In this chapter, those circumstances in which functional neuroimaging data can be used to infer awareness in the absence of a behavioural response will be contrasted with those circumstances in which it cannot. This distinction is fundamental for understanding and interpreting patterns of brain ‘activation’ following acute brain injury.

This chapter evaluates the tenability of the unity thesis by examining the evidence for phenomenal disunity within the context of number of quite different domains. The first third of the chapter addresses the question of whether the unity of consciousness might break-down in the context of the perceptual phenomena of apparent motion and meta‐contrast masking. The second third of the chapter examines objections to the unity thesis that appeal to data derived from studies drawn from developmental psychology. The final third of the chapter evaluates objections to the unity thesis derived from a cluster of conditions that are characterized by minimal responsiveness: the persistent vegetative state, the minimally conscious state, and epileptic fugue states. It is argued that none of these objections undermines the unity thesis.

This chapter examines what we know and are learning about the permanent vegetative state and the minimally conscious state, as well as the new, promising techniques to distinguish between the two. It also reviews the evidence about Terri Schiavo's condition.

This chapter reviews the diagnostic classification of disorders of consciousness, severe brain injuries that span a spectrum of brain states ranging from coma to the vegetative and minimally conscious states. The chapter makes the key point that brain states can – and do – evolve over time and that it is critical to be vigilant of changes that indicate that a patient who was unconscious is now conscious, albeit minimally so. The chapter describes how this traditional nosology is being challenged, and refined, by emergent technologies like neuroimaging and the ethical implications of this evolution for clinical practice and research. Specifically, the chapter addresses the challenge posed by discordant assessments when the clinical examination is brought into question by neuroimaging data that suggests that the patient is operating at a higher functional status than indicated by purely behavioral measures of assessment. Finally, drawing upon in-depth interviews of families touched by disorders of consciousness, the chapter explores family experiences and expectations, and suggests that these data indicates that the overriding goal of care, as understood by families, is the restitution of functional communication for this population silenced, at least in part, by disorders of consciousness.

After having discussed the role of the resting state and its prephenomenal structures, the volume now moves on to how they are manifested on the phenomenal level of consciousness. Qualia are considered the phenomenal hallmarks of consciousness that describe the subjective and qualitative features, the “what it is like” of experience and thus consciousness. The book here takes the loss of consciousness in the pathological disorder of the vegetative state (VS) as a paradigm to investigate the neuronal mechanisms underlying qualia in particular and consciousness in general.

Here we review the philosophical implications of the theory presented in previous chapters, and its consequences for future research. This leads us to demarcate the current theory from classical positions such as dualism, materialism, and functionalism. We discuss dualist arguments such as the case of philosophical 'zombies'. However, while these seem conceivable, they are argued not to be realizable: the construction of neural machinery appropriate for zombies would inevitably give rise to consciousness. Following a discussion of Jackson’s argument on “Mary the Color Scientist”, the reality of phenomenal experience is acknowledged as much as the reality of neural levels of processing, placing the theory away from eliminative materialism and classic functionalism. This characterizes the theory as a non-reductive, multilevel, neurobiological form of representationalism ('neurorepresentationalism'). Although representationalists have not been typically concerned with the problem of how neural aggregates give rise to consciousness, the “externalist” stream in this school is much more distant from the current view than the “narrow” stream emphasizing that representations are generated in and by the brain. Finally, we discuss consciousness in animals and in human-made inventions such as computers and robots, and on future treatment of disorders of consciousness.

Most philosophers agree that some sort of psychological continuity is necessary or sufficient for us to persist – the Psychological Approach to personal identity. Some implications of this view are sketched. The Biological Approach, by contrast, says that our identity, over time, consists in brute biological continuity.

Argues that we must have two concepts of death – the death or ceasing to exist of the person and the death of the human organism. Brain death is not the proper criterion for either of these. Persistent vegetative state involves the death or ceasing to exist of the person, even though the human organism continues to live. This chapter also defends the permissibility of assisted suicide and euthanasia in a broad range of cases and concludes by discussing the authority of advance directives in cases involving dementia.

This chapter discusses the United States Supreme Court Opinion on the case of Nancy Cruzan who had been severely injured in an automobile accident on January 11, 1983. It notes that Cruzan remained in a coma for approximately three weeks and then progressed to an unconscious state in which she was able to orally ingest some nutrition. It further notes that subsequent rehabilitative efforts proved unavailing and Cruzan was in a persistent vegetative state: generally, a condition in which a person exhibits motor reflexes but evinces no indications of significant cognitive function. It states that the Cruzan Majority in the United States Supreme Court endorsed the Missouri Supreme Court's presumption in favor of human life. It notes that this approach is identified as deeply grounded in the common law tradition.

After having discussed the direct relationship of the resting state activity to consciousness, the book now turns to stimulus-induced activity. More specifically, he aims to investigate how the purely neuronal stimulus-induced activity can become associated with consciousness and its phenomenal features. For that, it again relies on the loss of consciousness in the vegetative state (VS) as a paradigm.

This chapter explains and contrasts various scales that neurologists use to measure consciousness. These scales attempt to differentiate patients in a minimally conscious state from those in a vegetative state. They include the Glasgow Coma Scale, the Coma Recovery Scales, the Nociception Coma Scale, and the author’s own Coma Recovery Scale‒Revised. These scales are crucial for avoiding misdiagnosis and misunderstanding of patients with severe brain damage. Findings of studies on residual brain activity are described, with a focus on distinguishing conscious from unconscious states.

This chapter summarizes the recently developed methods by which neuroscientists can detect consciousness in severely brain-damaged patients. These methods involve the use of functional magnetic resonance imaging or electroencephalography to discern willful brain activity in patients and healthy volunteers. Subjects are asked to use mental imagery of particular motor functions, and these can be used to indicate answers to “yes or no” questions. The authors discuss how far these methods can succeed in determining thoughts, intentions, feelings, and other mental states in patients who show no outward signs of consciousness as well as the diagnostic and judicial implications.

In this chapter, Hardcastle questions whether consciousness determines how much we should care about a living being. Instead of consciousness, Hardcastle focuses on pain and argues that consciousness is not required for pain. We do not know what it is like to be in a minimally conscious state, and misdiagnoses are numerous. For these reasons, it is reckless to assume that patients who have been diagnosed as being in a permanent vegetative state or a minimally conscious state lack pain or consciousness. That assumption could result in extreme and extended suffering, so we should assume that pain is possible and treat it.

This chapter examines issues of social justice as it pertains to the provision of health care for individuals suffering from profound neurological injury and brain death. Advances in neurology enable detection of the presence or absence of activity in different parts of the brain, allowing doctors to sustain the lives of patients whose neurological damage prevents consciousness. These advances have, in turn, raised questions about what sort of care is owed to such individuals, for how long, and why. The chapter first provides a medical background on coma, brain death, vegetative state, minimally conscious state, and locked-in state before discussing the social and ethical implications of sustaining a patient like Terri Schiavo, including the justice of abiding by or rejecting the values of people who do not accept the brain death standard. It also considers the role of efficacy in resource distribution.

This introductory chapter begins with an overview of the Terri Schiavo case. In 1998, eight years after the collapse that caused Terri to enter a vegetative state, her husband, Michael Schiavo, began a long court battle to remove her feeding tube. Without it, Terri would certainly die. Michael insisted that this was what Terri would want. Her parents, Robert and Mary Schindler, disagreed. In court, they argued that Terri would not have wanted the feeding tube removed. The chapter then sets out the book's two main goals. The first is to provide an explanation of what happened and why in the battle over the removal of Terri Schiavo's feeding tube. A second aim is to see what lessons can be learned the Schiavo controversy in the larger context of the law, ethics, and culture of end-of-life decision making.

This chapter examines the impetus, motivations, and ultimate goals of the provision of basic care, and how these relate to the patient in a permanent vegetative state. It argues that while providing food and water to someone who hungers or thirsts is a most basic sign of human compassion and responsibility, such as not the case a person who cannot experience hunger or thirst. When a person's life has become only a biological effort, and when we recognize that nutrition and hydration are likely to be provided only to satisfy our own sense of caring rather than to respond to what the person can feel or would want, then we are not helping at all. The fear of letting another die when we might extend that life must be balanced by our understanding that we cannot use—or demand—another human being's existence to improve our own.

Chapter 4 is devoted to a critical consideration of brain-based objections to the sole reliance on the traditional criteria for determining death. Starting with the assumption that brain death constitutes physiological decapitation, some commentators have argued that it is absurd to maintain that brain dead bodies remain alive. We contend, however, that decapitation does not signify death, understood as the cessation of the functioning of the organism as a whole. In the second half of the chapter we critically examine the "higher brain" standard of death. According to this conception, "brain dead" individuals are dead not because they have ceased to function biologically but because they have irreversibly lost the capacity for consciousness. The higher brain standard founders for both theoretical and practical reasons: it depends on the inherently vague and contested concept of personhood; and no reliable criteria are available for diagnosing the irreversible absence of consciousness.

Hawkins sees the moral debates surrounding brain-damaged patients as coming down to two questions: whether the patients suffer and whether they derive benefit from their lives. In Hawkins’ view, life brings benefits only to those who have the capacities to form relationships and to value. Patients in permanent vegetative states and even minimally conscious states lack these capacities. For this reason, Hawkins defends the choice to allow such patients to die. In responding to the likely objection that such patients could express a desire to live, Hawkins questions the value of such messages on the basis that we cannot assess the quality of the decision making or the process behind it.