This introductory chapter attempts to clarify the philosophical, empirical, and theoretical bases on which a cognitive neuroscience approach to consciousness can be founded. We isolate three major empirical observations that any theory of consciousness should incorporate, namely (1) a considerable amount of processing is possible without consciousness, (2) attention is a prerequisite of consciousness, and (3) consciousness is required for some specific cognitive tasks, including those that require durable information maintenance, novel combinations of operations, or the spontaneous generation of intentional (...) behavior. We then propose a theoretical framework that synthesizes those facts: the hypothesis of a global neuronal workspace. This framework postulates that, at any given time, many modular cerebral networks are active in parallel and process information in an unconscious manner. An information becomes conscious, however, if the neural population that represents it is mobilized by top-down attentional amplification into a brain-scale state of coherent activity that involves many neurons distributed throughout the brain. The long-distance connectivity of these `workspace neurons' can, when they are active for a minimal duration, make the information available to a variety of processes including perceptual categorization, long-term memorization, evaluation, and intentional action. We postulate that this global availability of information through the workspace is what we subjectively experience as a conscious state. A complete theory of consciousness should explain why some cognitive and cerebral representations can be permanently or temporarily inaccessible to consciousness, what is the range of possible conscious contents, how they map onto specific cerebral circuits, and whether a generic neuronal mechanism underlies all of them. We confront the workspace model with those issues and identify novel experimental predictions. Neurophysiological, anatomical, and brain-imaging data strongly argue for a major role of prefrontal cortex, anterior cingulate, and the areas that connect to them, in creating the postulated brain-scale workspace. (shrink)

Our aim in this paper is to raise a question about the relationship between theories of responsibility, on the one hand, and a commitment to conscious attitudes, on the other. Our question has rarely been raised previously. Among those who believe in the reality of human freedom, compatibilists have traditionally devoted their energies to providing an account that can avoid any commitment to the falsity of determinism while successfully accommodating a range of intuitive examples. Libertarians, in contrast, have aimed to (...) show that either physical indeterminacy or a certain kind of agent causation can find a place in the world for what they take to be genuine freedom. Few have considered whether moral responsibility requires a commitment to conscious attitudes.2 Our question derives from a confluence of two sources. First, there is reason to think that conscious attitudes matter to theories of responsibility, either directly, as a result of the latter’s commitments, or indirectly, by virtue of the assumptions that they make about certain intuitive examples. Second, there is accumulating evidence suggesting that there aren’t any conscious mental states possessing the sorts of causal roles required of propositional attitudes. Since theorists of responsibility should in general be concerned to make their views compatible with plausible claims about the natural world, the implications of this data should be carefully considered. Our aim is therefore to motivate and begin exploring answers to the following conditional question: If it should turn out that there are no conscious attitudes, then what would be the implications of this fact (if any) for theories of responsibility? We propose that theorists who aren’t skeptics about moral responsibility should examine their accounts, asking whether their theories (or the examples that motivate them) could survive the discovery that there are no conscious judgments, decisions, or evaluations. Since we take it that moral theorizing in general should operate with the weakest possible empirical assumptions about the natural world, such theorists should consider whether their accounts could be motivated in such a way as to be free of any commitment to the existence of conscious attitudes.. (shrink)

In a recent paper in this journal, Matt King and Peter Carruthers argue that the common assumption that agents are only (or especially) morally responsible for actions caused by attitudes of which they are conscious needs to be rethought. They claim that there is persuasive evidence that we are never conscious of our propositional attitudes; we ought therefore to design our theories of moral responsibility to accommodate this fact. In this reply, I argue that the evidence they adduce need not (...) worry philosophers. There is an ongoing debate over the role that consciousness of our attitudes plays in morally responsible behaviour, but the evidence they produce does not favour either side. Even if we are not conscious of our propositional attitudes as such - even if we lack introspective access to their content - we nevertheless reliably come to know their content. There are systematic differences between those attitudes of whose content we come to be aware and those we do not, and these differences are directly relevant to our moral responsibility. Moreover, coming to be aware of the content of our attitudes has effects on our behaviour, and these effects are directly relevant to our moral responsibility. The causal route whereby we come to be conscious of the content of our attitudes is irrelevant to whether they play the right kinds of roles to distinguish between actions for which we are responsible and actions for which we ought to be excused. (shrink)