We introduce a distinction between cortical dominance andcortical deference, and apply it to various examples ofneural plasticity in which input is rerouted intermodally orintramodally to nonstandard cortical targets. In some cases butnot others, cortical activity `defers’ to the nonstandard sourcesof input. We ask why, consider some possible explanations, andpropose a dynamic sensorimotor hypothesis. We believe that thisdistinction is important and worthy of further study, bothphilosophical and empirical, whether or not our hypothesis turnsout to be correct. In particular, the question of how the distinction should be explained is linked to explanatory gapissues for consciousness. Comparative and absolute explanatorygaps should be distinguished: why does neural activity in aparticular area of cortex have this qualitative expressionrather than that, and why does it have any qualitativeexpression at all? We use the dominance/deference distinction toaddress the comparative gaps, both intermodal and intramodal (notthe absolute gap). We do so not by inward scrutiny but rather by expanding our gaze to include relations between brain, body and environment.

Key words: consciousness, cortical deference, cortical dominance, dynamic sensorimotor contingencies, explanatory gaps, neural plasticity, perceptual adaptation, phantom limbs, synaesthesia.

A significant impediment to the study of perceptual consciousness is our dependence on simplistic ideas about what experience is like. This is a point that has been made by Wittgenstein, and by philosophers working in the Phenomenological Tradition, such as Husserl and Merleau-Ponty. Importantly, it is an observation that has been brought to the fore in recent discussions of consciousness among philosophers and cognitive scientists who have come to feel the need for a more rigorous phenomenology of experience. The central thought of this paper is that art can make a needed contribution to the study of perceptual consciousness. The work of some artists can teach us about perceptual consciousness by furnishing us with the opportunity to have a special kind of reflective experience. In this way, art can be a tool for phenomenological investigation. The paper focuses on the work of Richard Serra and offers a comparison of his work with that of Tony Smith.

This paper investigates a new species ofskeptical reasoning about visual experience that takesits start from developments in perceptual science(especially recent work on change blindness andinattentional blindness). According to thisskepticism, the impression of visual awareness of theenvironment in full detail and high resolution isillusory. I argue that the new skepticism depends onmisguided assumptions about the character ofperceptual experience, about whether perceptualexperiences are ‘internal’ states, and about how bestto understand the relationship between a person’s oranimal’s perceptual capacities and the brain-level orneural processes on which they depend. I propose aconception of perceptual experience as a form ofskillful engagement with the environment on the partof the whole person or animal.

Key words: High resolution, recent work, blindness, full detail, perceptual experience.

As perceivers we are able to keep track of the ways in which our perceptual experience depends on what we do (e.g., on our movements). This capacity, which Hurley calls perspectival self‐consciousness, is a special instance of our more general ability as perceivers to keep track of how things are. I argue that one upshot of this is that perspectival self‐consciousness, like the ability to perceive more generally, relies on our possession of conceptual skills.

In this paper I explore a brand of scepticism about perceptual experience that takes its start from recent work in psychology and philosophy of mind on change blindness and related phenomena. I argue that the new scepticism rests on a problematic phenomenology of perceptual experience. I then consider a strengthened version of the sceptical challenge that seems to be immune to this criticism. This strengthened sceptical challenge formulates what I call the problem of perceptual presence. I show how this problem can be addressed by drawing on an enactive or sensorimotor approach to perceptual consciousness. Our experience of environmental detail consists in our access to that detail thanks to our possession of practical knowledge of the way in which what we do and sensory stimulation depend on each other.

“Perception is not something that happens to us, or in us, ” writes Alva Noë. “It is something we do. ” In Action in Perception, Noë argues that perception and perceptual consciousness depend on capacities for action and thought – that perception is a kind of thoughtful activity. Touch, not vision, should be our model for perception. Perception is not a process in the brain, but a kind of skillful activity of the body as a whole. We enact our perceptual experience. To perceive, according to this enactive approach to perception, is not merely to have sensations; it is to have sensations that we understand. In Action in Perception, Noë investigates the forms this understanding can take. He begins by arguing, on both phenomenological and empirical grounds, that the content of perception is not like the content of a picture; the world is not given to consciousness all at once but is gained gradually by active inquiry and exploration. Noë then argues that perceptual experience acquires content thanks to our possession and exercise of practical bodily knowledge, and examines, among other topics, the problems posed by spatial content and the experience of color. He considers the perspectival aspect of the representational content of experience and assesses the place of thought and understanding in experience. Finally, he explores the implications of the enactive approach for our understanding of the neuroscience of perception.

Excerpt: We perceive as much as we do because, in a way, we perceive so little. Traditional approaches to perception have found it difficult to accommodate the distinctive amodality of perceptual consciousness. Take vision, for example. If we think of what is visible in terms of projective geometry and artificial perspective, then, however paradoxical it may sound, vision is not confined to the visible. We visually experience much more than that. We experience what is hidden (occluded) and what is out of view. For example, we have a sense of the visual presence of the back of a tomato when we look at one sitting before us, even though the back of the tomato is out of view; and we experience the circularity of a plate, its actual shape, even when, seen from an angle, the circularity itself can’t be seen. Or consider your sense of the detail of the scene before your eyes now. You have a sense of the presence the detail; the scene is replete with detail. But it is not the case that you seem to yourself actually to see all the detail; you can no more see every bit of detail in sharp focus and high resolution than you can see the tomato from all sides at once. Just as the back of the tomato shows up in your experience although it is hidden from view, so the detailed scene before you shows up in your experience, although the detail outstrips by far what can be taken in at a glance. The world outstrips what we can take in at a glance; but we are not confined to what is available in a glance.

Our culture is obsessed with the brain―how it perceives; how it remembers; how it determines our intelligence, our morality, our likes and our dislikes. It’s widely believed that consciousness itself, that Holy Grail of science and philosophy, will soon be given a neural explanation. And yet, after decades of research, only one proposition about how the brain makes us conscious―how it gives rise to sensation, feeling, and subjectivity―has emerged unchallenged: we don’t have a clue. In this inventive work, Noë suggests that rather than being something that happens inside us, consciousness is something we do. Debunking an outmoded philosophy that holds the scientific study of consciousness captive, Out of Our Heads is a fresh attempt at understanding our minds and how we interact with the world around us.

In the past decade, the notion of a neural correlate of consciousness (or NCC) has become a focal point for scientific research on consciousness (Metzinger, 2000a). A growing number of investigators believe that the first step toward a science of consciousness is to discover the neural correlates of consciousness. Indeed, Francis Crick has gone so far as to proclaim that ‘we need to discover the neural correlates of consciousness. For this task the primate visual system seems especially attractive. No longer need one spend time attempting to endure the tedium of philosophers perpetually disagreeing with each other. Consciousness is now largely a scientific problem’ (Crick, 1996, p. 486). Yet the question of what it means to be a neural correlate of consciousness is actually far from straightforward, for it involves fundamental empirical, methodological, and philosophical issues about the nature of consciousness and its relationship to the brain. Even if one assumes, as we do, that states of consciousness causally depend on states of the brain, one can nevertheless wonder in what sense there is, or could be, such a thing as a neural correlate of consciousness.

Our aim in ‘Are There Neural Correlates of Consciousness?’ was to call attention to some problematic assumptions of one widespread approach to investigating the relation between consciousness and the brain – the research programme based on trying to find neural correlates of the contents of consciousness (content-NCCs). Our aim was not to cast doubt on the importance of neuroscientific research on consciousness in general (contrary to Baars’s impresssion). Nor was it to engage in philosophical debates far removed from the concerns of scientists (as McLaughlin & Bartlett may think). Rather, it was to target some problematic assumptions of a particular empirical research programme, and by bringing them to light, to suggest that there may be other, more profitable ways to investigate the contribution of brain processes to conscious experience than searching for content NCCs. Most of the commentators (Bayne, Freeman, Hardcastle, Haynes & Rees, Hohwy & Frith, Metzinger, Myin, Roy, Searle, Van Gulick), though certainly not all (Baars, Jack & Prinz, McLaughlin & Bartlett) seem to have read us this way, and we are grateful for their critical reflections on our article. In this Authors’ Reply, we cannot respond in detail to every point raised by the commentators, so we shall limit ourselves to addressing the most important issues that we see arising from the commentaries collectively.