Tutorial workshops

Tutorials will take place on Friday June 23, 2006. Each tutorial will last three hours. The maximum number attendees in a tutorial will be restricted to about 25 people to allow ample opportunities for interactions between presenters and audience. Please feel free to contact presenters via email if you would like to know more about a particular session. The cost of attendance is £35 per tutorial.

MORNING

M1. Marbach: Phenomenological methods for investigating consciousness
M2. O'Regan: The sensorimotor approach to phenomenal consciousness revisited
M3. Tsuchiya & Koch: The relationship between selective attention and consciousness
M4. Verleger: Event-related EEG potential correlates of conscious perception

AFTERNOON

A1. Aleksander, Chrisley, & Shanahan : Machine models of consciousness
A2. Cowey: Exploring aspects of consciousness by TMS
A3. Edelman & Seth: A scientific framework for the study of animal consciousness
A4. Rosenthal: Higher-Order Theories of consciousness



Morning Sessions


M1. Phenomenological methods for investigating consciousness

Eduard Marbach

University of Bern
Institute of Philosophy
Unitobler, Laenggass-Strasse 49A
CH-3009 BERN
Switzerland

Email: eduard.marbach@philo.unibe.ch

Timetable

Each section will take approximately one hour

  1. Basic first-person methods of philosophical phenomenology: reflection and reduction; formation of phenomenological concepts;
  2. Doing phenomenology: examples of detailed analyses of structures of conscious experiences, using a phenomenological notation;
  3. Combining first-person methods with scientific third-person methods and data, illustrated with cognitive neuroscience studies of imagery and episodic memory.

Abstract

This workshop will introduce to the (auto-)phenomenological study of consciousness in the tradition of the philosopher Edmund Husserl (1859 1938). The main emphasis will be on explicating and practicing how one does phenomenology; for Husserl was particularly careful in elaborating methodical tools for the first-person study of consciousness. In his analyses, Husserl has been inspired by mathematics, proceeding by way of contrasting conscious experiences of distinctly different structures (as they obtain in, e.g., perceiving something, in episodic remembering, in merely imagining something, in picturing something, or in judging about a state of affairs, etc.) in order to establish those invariant components that make up the specific structures of conscious experiences of one kind or another. An important aspect of Husserl's pre-experimental, philosophical enterprise concerns the question to what extent a first-person reflective clarification of structures of conscious experiences could serve as a guide for cognitive neuroscientific studies much more specifically than would be possible without a rigorous (auto-)phenomenological analysis preceding the scientific work. Quite generally, this aspect of bringing together first-person phenomenological methods and third-person scientific methods, including Dennettian heterophenomenology, would seem to be of utmost importance for making progress in the scientific study of conscious experiences, given that a specification of the explananda can only help the elaboration of the corresponding explanantia. Participants of the workshop should get a good grasp of the first-person phenomenological methodology, and ideally even discover ways for making good use of phenomenology in the advancement of the scientific study of consciousness.

Reading list

  1. Zahavi, Dan. Husserl's Phenomenology. Stanford University Press, 2003, chapters 1 and 2.
  2. Smith, David Woodruff. "Phenomenology". Stanford Encyclopedia of Philosophy online at http://plato.stanford.edu/entries/phenomenology/
  3. Gallagher, Shaun. "Phenomenology and Experimental Design. Toward a Phenomenologically Enlightened Experimental Science". Journal of Consciousness Studies 10.9/10 (2003): 85-99.
  4. Marbach, Eduard. "On Bringing Consciousness Into the House of Science - With the Help of Husserlian Phenomenology". http://www.philosophie.unibe.ch/E.%20Marbach%20Angelaki%20vol.10,%20no.%201,%202005,%20145-162.pdf. Angelaki. Journal of the theoretical humanities. Special issue: Continental philosophy and the sciences, the German tradition. Issue editor: Damian Veal, volume 10, number 1 (2005): 145-162 (available online).

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M2. The Sensorimotor approach to phenomenal consciousness revisited and frequently asked questions answered

J. Kevin O'Regan

Laboratoire Psychologie de la Perception
Centre National de Recherche Scientifique
Institut de Psychologie, Centre Universitaire de Boulogne
71, avenue Edouard Vaillant
92774 Boulogne-Billancourt Cedex
France

Email: oregan@ext.jussieu.fr

web: http://nivea.psycho.univ-paris5.fr

Timetable

30 minutes for the brief recap of the sensorimotor theory, followed by 50 mins for each of the other sections listed below. Ê

Abstract

After briefly synthesizing the current formulation of the sensorimotor approach to phenomenal consciousness, and after quickly reviewing recent empirical results (in particular on colour) and theoretical developments (on pain), the tutorial's main purpose will be to address and discuss (with the help of participants):

Common misunderstandings about the sensorimotor approach

  • Why it does not deny representations
  • Why it does not claim action is required for perception
  • Why hallucinations, dreams and imagery do not contradict it
  • Why it does not deny 'qualia' nor simply explain 'away' phenomenal consciousness
  • Why appealing to cognitive access does not make it circular
  • Why the approach is not a denial of the brain

Relation to other approaches

  • Why the sensorimotor approach is different from the enactive and dynamical systems approaches
  • How the sensorimotor approach is different from behaviorism
  • How it's different from Gibson's ecological approach
  • Is it just a form of functionalism? Is it eliminativist?
  • Is it just another higher order thought theory?
  • How does it differ from global workspace type models?
  • In what way does the approach differ from Dennett's?
  • What is the relation to Merleau Ponty/Heidegger/Bergson/Al Hazen

Limits of the approach

  • What does the theory have to say about the dorsal-ventral distinction, cortical maps, filling-in, mirror neurons, face areas?
  • How does it deal with inverted qualia and the knowledge argument?
  • What does it say about emotions? The notion of self? Free will? The experienced quality of thoughts?
  • Does the approach need a leap of faith?
  • Can the sensorimotor approach be tested (ie is it a scientific theory)?

Reading list

  1. O'Regan, J.K., Myin, E. & Noe, A. Skill, corporality and alerting capacity in an account of sensory consciousness. In: S. Laureys (Ed.) Progress in Brain Research, Vol 150, pp 55-68, 2005. URL: http://nivea.psycho.univ-paris5.fr/Mss/oregan_PBR_vol150_055_068.pdf.

NB: from April 2006, a collaborative web site will be available to prepare the discussion at the tutorial: URL: http://lpp.psycho.univ-paris5.fr/tikiwiki/.

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M3. The relationship between selective attention and consciousness

Naotsugu Tsuchiya and Christof Koch

California Institute of Technology
1200 E California Blvd
Pasadena, CA, 91125

Email: naotsu@gmail.com

Timetable

Approximately 30 minutes devoted to each segment.

  1. Background
    1. Definition of the terms (attention, access versus phenomenal consciousness);
    2. Historical views on the concept of attention and consciousness;
    3. Neuronal basis of attention and consciousness. Can we separate the neuronal correlates of attention from consciousness?
  2. Recent findings in psychophysics
    1. Can we attend to invisible stimuli?
    2. Is attention necessary to get unconscious processing?
    3. Can attention and consciousness result in the opposite directions?

Abstract

Historically, the pervading assumption among sensory psychologists is that what a subject attends to is what she is conscious of. That is, attention and consciousness are very closely related, if not identical, processes. However, a number of recent authors have argued that these are two distinct processes, with different neuronal mechanisms. While the neuronal correlates of consciousness remain elusive, significant progress has been made in studying the neuronal correlates of "unconscious" processing; a multitude of techniques---such as masking, crowding, attentional blink, motion-induced blindness, continuous flash-suppression, and binocular rivalry---permit visual scenes to be presented to subjects without subjects becoming aware of them. Such experiments, coupled to fMRI in humans and single-cell recordings in behaving monkeys, show that vigorous hemodynamic and spiking activity in cortex is often not associated with conscious perception. In this tutorial, we review the experimental literature and argue 1) that invisible stimuli can be attended with top-down attention and can influence subsequent behavior, 2) that to observe some behavioral evidence of unconscious processing, top-down attention to invisible stimuli is necessary and 3) that under some conditions top-down attention and consciousness can result in opposite effects. The philosopher Ned Block has argued on conceptual grounds for two forms of consciousness, access (A) and phenomenal (P) consciousness. Given the data, it may be possible that A is equivalent to top-down attention and read-out (which usually, but not always, goes hand-in-hand with P) while P can occur with or without top-down attention.

Reading list

  1. Block N (2005) Two neural correlates of consciousness. Trends Cogn Sci 9:46-52. URL: http://www.nyu.edu/gsas/dept/philo/faculty/block/papers/longerTiCS.pdf.
  2. Koch C (2004) The Quest for Consciousness: A neurobiological Approach. CO: Roberts and Publishers.
  3. Lamme VA (2004) Separate neural definitions of visual consciousness and visual attention; a case for phenomenal awareness. Neural Netw 17:861-872. URL: http://www.nyu.edu/gsas/dept/philo/courses/consciousness05/LammeNetworks.pdf.
  4. Suzuki S, Grabowecky M (2003) Attention during adaptation weakens negative afterimages. J Exp Psychol Hum Percept Perform 29:793-807. URL: www.psych.northwestern.edu/psych/people/faculty/suzuki/PDF's/Suzuki&Grabowecky'01a.pdf.
  5. Tsuchiya N, Koch C (2005) Continuous flash suppression reduces negative afterimages. Nat Neurosci 8:1096-1101. (Available at http://www.klab.caltech.edu/cgi-bin/publication/reference-view.pl?refdbname=paper&paper_id=510)

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M4. Event-related EEG potential correlates of conscious perception: The P3 and N2pc components

Rolf Verleger

Department of Neurology
University of Lubeck
D 23538 Lubeck

Email: rolf.verleger@neuro.uni-Luebeck.de

Timetable

Each section will take 20-30 minutes

  1. Evidence linking P3 to conscious awareness
  2. Evidence linking N2pc to conscious awareness
  3. ERP Studies on Hemi-Neglect
  4. Theory of N2pc
  5. Theory of P3
  6. Final Discussion

Abstract

Averaged event-related EEG potentials (ERPs) indicate cortical activity with extremely good temporal resolution and therefore continue being the most illustrative means of looking at the brain's activities in perceiving single events. For decades, the P3 (or P300) component of the ERP has been linked to conscious awareness of stimuli. More recently, similar claims have been raised with regard to the N2pc component. This tutorial will provide basic knowledge about psychological and neurophysiological aspects of P3 and N2pc and will give a detailed account of the relevant evidence that relates P3 and N2pc, as well as other ERP components, to conscious awareness, focusing on evidence from studies on conscious vs. non-conscious perception and from studies on hemi-neglect patients. The discussion is open for new, more detailed theories about the functional meaning of these components, based on the available evidence of their neurophysiological basis and of their psychological determinants.

Reading list

  1. Vogel, E.K., Luck, S.J., & Shapiro, K.L. (1998) Electrophysiological evidence for a postperceptual locus of suppression during the attentional blink. Journal of Experimental Psychology: Human Perception and Performance 24:1656-1674. URL: http://www.psychology.uiowa.edu/faculty/Luck/lucklab/pdfs/Vogel_1998_JEPHPP.pdf.
  2. Deouell, L. (2002) Pre-requisites for conscious awareness: Clues from electrophysiological and behavioral studies of unilateral neglect patients. Consciousness and Cognition 11:546-567. http://pissaro.soc.huji.ac.il/~leon/Lab/PDFs/prerequisites_for_awareness.pdf
  3. Verleger R, Jaskowski P (2006) Effects of masked stimuli on attention and response tendencies as revealed by event-related EEG potentials. Possible application to understanding neglect. In: …gmen H, Breitmeyer B, Eds, The First Half Second: The Microgenesis and Temporal Dynamics of Unconscious and Conscious Visual Processes. Cambridge (Mass.): MIT Press, in press. URL: http://www.neuro.uni-luebeck.de/PDF/AGVerleger/B56%2Epdf.
  4. Sergent, C., Baillet, S., & Dehaene, S. (2005) Timing of the brain events underlying access to consciousness during the attentional blink. Nature Neuroscience 8:1391-1400. URL: http://www.unicog.org/publications/SergentBailletDehaene_AttentionalBlinkConsciousness_NatNeurosci2005.pdf.

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Afternoon sessions

A1. Machine models of consciousness

Igor Aleksander, Ron Chrisley, and Murray Shanahan

Department of Electrical and Electronic Engineering
Imperial College
London SW7 2BT
U.K.

Email: i.aleksander@imperial.ac.uk

Timetable

Each section approximately one hour in length.

  1. Computational modelling: Review of the work of Baars, Chrisley, Haikonen. These models aim at capturing behaviour through computational means. They include important frameworks within which consciousness can be discussed as an informational structure. Presenter: Ron Chrisley
  2. The challenge of anatomy and phenomenology: Review of Edelman, Taylor, Cotterill and Aleksander. These models take cognisance of brain architecture and the properties thought necessary for the creation of a representation that have a phenomenal character. Presenter: Igor Aleksander
  3. Implications for robotics: Review of Kritchmer, Shanahan and Holland. Here the modelling is grounded in the behaviour of a robot. The work includes architectures for navigation and action selection. Presenter: Murray Shanahan

Abstract

The work of several laboratories on the modelling of consciousness is reviewed. This ranges, on one hand, from purely functional models where behaviour is important and leads to an attribution of consciousness, to, on the other hand, material work closely derived from what is known about the anatomy of the brain and addresses the problem of phenomenology. At the functional end of the spectrum is the attribution of consciousness by a user to an artefact that is reviewed (Franklin) as well as general schematic frameworks (Sloman/Chrisley, Haikonen). At the material end, attempts at modelling brain mechanisms (Edelman, Baars), and basic bio-chemical processes are discussed (Taylor/Cotterill). There are also general prescriptions for functional schemas which facilitate discussions for the presence of consciousness in computational systems and axiomatic structures that define necessary architectural features without which it would be difficult to represent sensations (Aleksander). Another distinction between these two approaches is whether one attempts to model phenomenology (material end) or not (functional end). The former is sometimes called 'synthetic phenomenology'. Finally the work of those who use robot vehicles is reviewed (Kritchmer, Shanahan and Holland).

Reading list

  1. Sloman A. Chrisley R.: Virtual Machines and Consciousness, Journal of Consciousness Studies, 10(4-5), 2003, 133-172(40). URL: http://www.cs.bham.ac.uk/research/cogaff/sloman-chrisley-jcs.pdf.
  2. Aleksander I., Dunmall B: Axioms and Tests for the Presence of Minimal Consciousness in Agents Journal of Consciousness Studies, 10(4-5), 2003, 7-18(12).
  3. Shanahan, M: Consciousness, Emotion, and Imagination A Brain-Inspired Architecture for Cognitive Robotics. In Proc. AISB 2005 Workshop: Next Generation Approaches to Machine Consciousness, pp. 26-35 http://www.aisb.org.uk/publications/proceedings.shtml.

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A2. Exploring aspects of consciousness by TMS

Alan Cowey

Department of Experimental Psychology
Oxford University
South Parks Road
Oxford OX1 3UD
U.K.

Email: alan.cowey@psy.ox.ac.uk

Timetable

Roughly 45 minutes devoted to each of four sections.

  1. History of attempts to stimulate the brain electrically, from Fritsch and Hitzig (1870) and Ferrier (1873) to Penfield and his collaborators in the middle of the last century and Brindley and Lewin in 1968. Why stimulating the brain directly might throw light on functional localization and perceptual awareness.
  2. The nature of magnetic induction and why it is not necessarily a simple way of selectively exciting the cortex beneath the stimulating coil.
  3. Examples of the triumphs and drawbacks of using TMS to understand visual cognition and visual awareness.
  4. What we can now realistically expect from the use of TMS - alone or in combination with other techniques like EEG and fMRI - to study awareness, including increased awareness as well as disrupted awareness.

Abstract

Transcranial magnetic stimulation (TMS) is a technique now widely used to study brain function. Unfortunately it is also widely misunderstood, even by some of us who use it. TMS allows us to stimulate parts of the cerebral cortex and underlying white matter by a brief electrical current induced by a similarly brief, rapidly fluctuating magnetic field which is itself produced by rapidly discharging a current through an insulted coil held against the scalp. TMS can produce positive signs, such as movements or phosphenes (illusory visual percepts), but its major effect when applied beyond sensory or moror cortex is to disrupt cortical processing, which is reflected in longer response times and/or a failure to be aware of particular sensory events. When combined with magnetic resonance structural and functional images of the subject's brain the stimulation can be directed at specific cortical areas. Over a period of only 15 years TMS has revealed hitherto unsuspected aspects of brain function, such as the role of distant parts of the brain in recovery from stroke, and has helped to resolve several previously intractable disputes, notably the neuronal basis of conscious awareness. The proposed workshop would describe and discuss the origins and nature of TMS, its applications and limitations, and its especial usefulness in conjunction with other techniques of evaluating or imaging brain activity. The technique would also be demonstrated.

Reading list

Numbers 1, 3 and 4 are reviews. Number 2 is a short experimental paper that makes a particularly important point More detailed references will be provided with the tutorial.

  1. Cowey, A. The Ferrier Lecture 2004. What can transcranial magnetic stimulation tell us about how the brain works? Philosophical Transactions of the Royal Society, London, B. 360, 1185-1205, 2005. URL: this link requires a subscription to the journal.
  2. Silvanto, J., Cowey, A., Lavie, N. and Walsh, V. Striate cortex (V1) activity gates awareness of motion. Nature Neuroscience, 8, 143-144, 2005. URL: http://www.psychol.ucl.ac.uk/attention.lab/reprints/Silvanto-et-al-NN-2005.pdf.
  3. Walsh, V. and Cowey, A. Transcranial magnetic stimulation and cognitive neuroscience. Nature Reviews Neuroscience, 1, 73-79, 2000. URL: http://www.indiana.edu/~iung/fmriPapers/review_walsh.pdf.
  4. Walsh, V. and Cowey, A. Magnetic stimulation studies of visual cognition. Trends in Cognitive Sciences, 2, 103-110, 1998. this link requires a subscription to the journal.

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A3. A scientific framework for the study of animal consciousness

David Edelman and Anil Seth

The Neurosciences Institute
10640 John Jay Hopkins Drive
San Diego, California 92121

Email: david_edelman@nsi.edu
Email: seth@nsi.edu

Timetable

The tutorial will be divided into three 45 minute sessions. After each session, fifteen minutes will be devoted to discussion among audience members and presenters.

  1. Present a picture of animal consciousness (i.e., which species are likely to possess it) that has been gleaned from comparative psychological, physiological, and anatomical studies;
  2. draw a clear distinction between sensory and higher order consciousness and justify that distinction;
  3. lay out an interdisciplinary framework for the study of animal consciousness.

Abstract

Accurate report of conscious experience is the benchmark of consciousness studies in humans. In species without a language faculty, however, accurate reports are difficult to acquire. Fortunately, recent advances in functional neuroanatomy, neurophysiology, and genetics offer alternative strategies for amassing evidence for consciousness in non-human mammals, birds, and possibly other species. It is now possible to pursue evolutionary homologies in anatomical substrates and to measure physiological correlates of conscious states across species [1]. For example, the basic structure of the thalamocortical complex seems to have been conserved among mammals for some 200 million years. Moreover, data from human studies can provide a benchmark, and frame of reference, as we search for evolutionary homologs or analogs of the substrates of consciousness in non-human animals. We know, for instance, that an intact thalamocortical system is necessary for mammalian consciousness [2], and there are suggestive similarities between this system and structures in the avian brain. Finally, creative means can be developed for eliciting behaviors consistent with consciousness (e.g., the "commentary key" paradigm employed by Cowey and Stoerig in their studies of blindsight in monkeys [3]). This tutorial will 1) present a picture of animal consciousness (i.e., which species are likely to possess it) that has been gleaned from comparative psychological, physiological, and anatomical studies; 2) draw a clear distinction between sensory and higher order consciousness and justify that distinction; and 3) lay out an interdisciplinary framework for the study of animal consciousness.

Reading list

  1. Edelman, D.B., B.J. Baars, and A.K. Seth. 2005. Identifying the hallmarks of consciousness in non-mammalian species. Consciousness and Cognition, 14(1): pp.169-187. URL: http://www.nsi.edu/users/seth/Papers/HallmarksWeb.pdf.
  2. Seth, A.K., B.J. Baars, and D.B. Edelman. 2005. Criteria for consciousness in humans and other mammals. Consciousness and Cognition, 14(1): p. 119-139. URL: http://www.nsi.edu/users/seth/Papers/SethEdelmanBaarsCC.pdf.
  3. Cowey, A. & Stoerig, P. 1995. Blindsight in monkeys. Nature, 373(6511): pp.247-249. URL: http://www.nature.com/cgi-taf/DynaPage.taf?file=/nature/journal/v373/n6511/abs/373247a0.html.

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A4. Higher-Order Theories of Consciousness

David M. Rosenthal

Program in Philosophy and Interdisciplinary Concentration in Cognitive Science
Graduate Center
City University of New York
365 Fifth Avenue
New York, NY 10016-4309

Email: davidrosenthal@nyu.edu

Timetable

30 minutes devoted to each segment

  1. Theories
    1. Higher-order versus first-order theories
    2. Alternative versions: higher-order thoughts versus higher-order perceiving, and occurrent versus dispositional higher-order states
    3. Distinct higher-order states versus intrinsic higher-order content
  2. Applications
    1. Qualitative consciousness
    2. The function of consciousness, and why higher-order states occur
    3. Consciousness and speech, blindsight, and timing

Abstract

Any satisfactory theory of consciousness must explain how conscious thoughts, feelings, and perceptions differ from those which are not conscious. One promising explanation starts by noting that, whenever such states are conscious, we are conscious of those states, whereas we're never conscious in the same way of mental states that aren't conscious. Being conscious of something, moreover, requires being in some mental state that pertains to that thing. It's natural to conclude that a mental state is conscious only if there is some higher-order state in virtue of which one is conscious of the state that's conscious. Such is the basic motivation for the higher-order theories of consciousness that have proliferated over the last 20 years.

Alternative higher-order approaches differ on several crucial issues. Do the requisite higher-order states resemble perceiving? Or are they thoughts? And does consciousness require occurrent higher-order states? Or do dispositions suffice? Further, must we posit distinct higher-order states, or might the requisite higher-order content be intrinsic to conscious states. Finally, some have raised a challenge to all higher-order theories, arguing that we aren't actually conscious of those thoughts, perceptions, and feelings which occur consciously. These issues will occupy the first half of the workshop.

In the second half, we'll consider several specific applications of higher-order theories. The first is how these theories might explain conscious qualitative character: How can higher-order states result in there being something it's like for one to be in qualitative states? And can higher-order states explain all the subtle qualitative variation that occurs among conscious states?

The second application concerns the function of consciousness. Can higher-order theories explain what role, if any, is played by mental states' being conscious? Are there selection pressures that might have made such higher-order states adaptive? If not, why would higher-order states occur so often, and why would they typically be so accurate?

Finally, we'll briefly consider how higher-order theories can accommodate the strong intuitive tie between consciousness and speech, as well as such dissociative disorders as blindsight and the striking results about timing found in experimental work by Benjamin Libet and Patrick Haggard.

Reading list

  1. Rosenthal, David M., "Explaining Consciousness," in David J. Chalmers, ed., Philosophy of Mind: Classical and Contemporary Readings, New York: Oxford University Press, 2002, pp. 406-421 (available online at http://web.gc.cuny.edu/cogsci/explg.pdf).
  2. Dretske, Fred, Naturalizing the Mind, MIT Press/Bradford Books, 1995, ch. IV, "Are Experiences Conscious?"
  3. Lycan, William G., "The Superiority of HOP to HOT," Rocco J. Gennaro, ed., Higher-Order Theories of Consciousness, Amsterdam and Philadelphia: John Benjamins Publishers, 2004, pp. 93-113 (available online at http://www.unc.edu/~ujanel/HOPHOT.htm
  4. Carruthers, Peter, "Higher-Order Theories of Consciousness," Stanford Encyclopedia of Philosophy, online at http://plato.stanford.edu/entries/consciousness-higher/.
  5. Levine, Joseph, Purple Haze: The Puzzle of Consciousness, New York: Oxford University Press, 2000, ch. 3.
  6. Rosenthal, David M., "Sensory Quality, Consciousness, and Perception," ch. 7 of Rosenthal, Consciousness and Mind, Oxford: Clarendon Press, 2005, pp. 175-226.