Here is a link to a paper by Evan Thompson clarifying the relation of consciousness to perception:
Look Again: Consciousness and Mental Imagery
Evan Thompson
http://espra.scicog.fr/LookAgain.pdf
Extract:
". . . conceptual confusion remains about the nature of imagery experience and its relation to the brain and behavior. If there is to be progress in understanding mental imagery, let alone any “resolution of the imagery debate,” 7 then we need to do better.
Using imagery research as an exemplar, I intend to show how cognitive science stands to gain from phenomenological analysis of experience. Let me explain what I mean by phenomenology for the purposes of this paper.
Phenomenology is concerned with what constitutes the experience of a given sort of activity, such as perceiving or imagining. It focuses not simply on the qualitative character of what is experienced, the objects of experience, but also on the subjective character of the activity itself, the acts of experiencing. For example, a phenomenological analysis focuses not only on the qualitative character of what we see— color, shape, things in space, and so on; it focuses also on what the activity of seeing is like, on what it feels like to encounter the world visually. Phenomenology is concerned with what seeing is like, as compared with hearing, or imagining, or remembering. What experience is like in this sense is constitutive of what experience is. Phenomenology is thus concerned with the constitution of experience.
Phenomenology understood in this way includes any philosophical analysis that makes the qualitative and subjective character of experience its subject matter. It is not limited to the phenomenological school or tradition stemming from Husserl. Nevertheless, this tradition’s analyses of imagery experience offer resources for understanding mental imagery untapped by cognitive science, and they inspire much of what I have to say in this paper. 8
Phenomenological analysis operates at the personal level. When we describe experience we are describing experiential contents and activities as belonging to the whole person, and our descriptions have a holistic and normative character. We describe the interrelations of perceiving, intending, feeling, imagining, and acting, and we try to make sense of these interrelations in various norm-governed ways. By contrast, when we describe the neural processes on which experience depends, we are describing subpersonal phenomena, and our descriptions do not have this holistic and normative character. When, for example, in an experiment on mental imagery, I attribute to you a certain mental state, such as visualizing the rotation of some geometrical figure, I make an attribution at the personal level. Whether this attribution makes sense depends partly on what else I take you to believe (e.g., about object geometry and spatial relations, but also about your understanding of the task instructions). On the other hand, when I attribute to an area of your brain a certain pattern of electromagnetic activity, I make an attribution at the subpersonal level, and this attribution is not subject to these sorts of holistic and normative considerations.
Phenomenological analysis can do important philosophical and scientific work. It can help to clarify the conceptual relation between accounts of experience at the personal level and accounts of the brain at the subpersonal level, and it can help to guide experimental research in cognitive science.
In this paper, I sketch a phenomenological analysis of imagery experience. Its main upshot is to challenge the widespread belief in cognitive science that imagery experience is the experience of “phenomenal mental images.” As we will see, both pictorialists and descriptionalists, the two rivals of the imagery debate, accept this characterization of imagery experience; what they disagree about is whether the subpersonal representations used in visual problem-solving are depictive or propositional in form. I argue, however, that in visual imaging or visualizing, we do not experience phenomenal mental images (“pictures in the head”), but rather mentally represent visual experiences to ourselves in certain ways. The content of these experiences (either as actual visual experiences or as mentally represented ones) cannot be given in an image or picture. On the basis of this phenomenological analysis, I propose an alternative to both pictorialism and descriptionalism. My proposal also builds on the enactive or dynamic sensorimotor approach to perception in cognitive science. 9 According to my enactive proposal, visualizing is the vicarious exercise of the skillful sensorimotor knowledge actually exercised in perception.
I. Experience and the Imagery Debate
The subjective experience of mental imagery has occupied a problematic place in the imagery debate since this debate’s inception in the early nineteen-seventies. On the one hand, everyone agrees that the experience of imagery exists and that any adequate theory of imagery must ultimately be able to account for it. On the other hand, the main concern of imagery theories has not been to explain imagery experience, but rather to explain the ability of individuals to solve problems in various kinds of cognitive tasks in which they report using imagery. Examples are judging whether two objects of different orientation have identical shapes by “mentally rotating” one to see whether it can be brought into correspondence with the other, or “mentally scanning” a visualized map in order to determine whether a particular object is present on it. 10 Although imagery research relies on reports of imagery experience as a source of data, the two main rival theories of imagery, pictorialism and descriptionalism, have left imagery experience as such unaccounted for.
Pictorialism and descriptionalism are theories about the subpersonal representations and processes that are supposed to be causally implicated in imagery tasks. According to pictorialism (whose principal exponent is Stephen Kosslyn), these representations are depictive or pictorial, which means that they represent by virtue of their spatial format. In a depictive representation, each part of the object is represented by a pattern of points, and the spatial relations among these patterns correspond to the spatial relations among the object’s parts. 11 It is well known, for example, that area V1 of the visual cortex in primates is organized retinotopically. In other words, neurons in this area are organized in a way that roughly preserves the spatial structure of the retina. Although this cortical representation of the retina is laid out in physical space, the depictive space need not be physical, according to Kosslyn, but could be specified purely functionally, like an array in a computer. On the other hand, according to descriptionalism (whose principal exponent is Zenon Pylyshyn), the mental representations involved in vision and imagery represent by virtue of their propositional structure. Pylyshyn argues that the notion of a purely functional space has no explanatory value in accounting for the actual format of mental representations. 12 He also argues that the activation of retinotopically organized brain areas in visual mental imagery (which remains controversial) 13 does not show that imagery or vision involves depictive representations laid out in the physical space of the brain, for mental images and topographical patterns of activation in V1 fail to correspond in numerous ways (e.g., the 3D spatial structure of what we perceive or imagine was never present on the 2D retina or its retinotopic cortical projections). 14 On Pylyshyn’s descriptionalist view, imagery is the representation of how things look or would look, based on our tacit propositional knowledge of visual properties and relations.
Although scientific research on imagery designed to test these two theories must rely on first-person reports of imagery experience as an indispensable source of data, neither descriptionalism nor pictorialism provides any explanatory bridge back to imagery experience at the personal level from their postulated subpersonal representations. Imagery experience is used on the way in, but is left in limbo on the way out. . . . ."