Below are the 45 oral presentations to be delivered in concurrent sessions 1 to 3 during ASSC6.
Disunified Access to a Unified Consciousness?
Tim Bayne (email@example.com)
Department of Philosohpy
Many disorders of consciousness have the following structure: the patient is able to report one state of consciousness (S1) in one report modality but not in another report modality, yet they are also able to report another state of consciousness (S2) with the second report modality but not with the former. For example, when exposed to the word "tea-cup" a split-brain patient may say that she saw the word "cup" but not the word "tea". Yet, if asked to produce a left-handed written report of what she saw, the patient may write the word "tea." Similar dissociations in reportability can be found in unilateral neglect, the "hidden observer" in hypnosis, and Marcel's experiments. Most commentators assume that such dissociation in report modality provides evidence for disunity in the phenomenal structure of the subject's consciousness. Such a position seems to rest on the tacit assumption that it is not possible for phenomenally unified states of consciousness to be accessible to distinct report-modalities. I argue that this assumption is unwarranted, and that disunity in access to consciousness doesn't settle the question of disunity in the structure of phenomenal consciousness.
Knowing 'where' without knowing 'what': Orienting and spatial localization in the split brain
Diego Fernandez-Duque & Sandra E. Black
Diego Fernandez-Duque (firstname.lastname@example.org)
Cognitive Neurology, A421
Sunnybrook and Women's College
Health Science Centre
University of Toronto
CANADA, M4N 3M5
A patient with posterior callosotomy and right mediofrontal stroke was assessed in his ability to recognize and localize objects, as well as in the ability to split attention between and within visual hemifields. When a set of pac-men was briefly displayed in the right visual field, the patient was able to recognize both shape and location. In contrast, when stimuli were displayed in the left visual field, he was unable to report object features either verbally or with his right hand. These data reveal an impaired callosal transfer of object information. In contrast, spatial localization of objects was unimpaired, even in the left visual field. A covert orienting task revealed that attention was split more effectively between visual hemifields than within a given hemifield, a result that suggest a possible role of spatial attention in the localization of unrecognized objects.
FUNDING SUPPORT: This research was supported by a post-doctoral fellowship from the Rotman Research Institute, and by grants to the first author from the Heart and Stroke Foundation of Ontario, and by the Center for Consciousness Studies of the University of Arizona.
'K' is for ketamine: an fMRI study of the neural correlates of a ketamine-induced psychotic state on word generation
Cynthia H.Y. Fu, Kathryn Abel, Matthew Allin, Nanda Vythelingum, Sergi Costafreda, Steve C.R. Williams & Philip K. McGuire
Cynthia H.Y. Fu (email@example.com)
Section of Neuroimaging
Division of Psychological Medicine
Institute of Psychiatry
King's College London
De Crespigny Park
London SE5 8AF
Phencyclidine (PCP) produces a brief psychotic state in healthy volunteers that is comparable with the symptoms of schizophrenia. A fundamental neurocognitive deficit in schizophrenia is impairments in language processing. Letter verbal fluency is a classical measure of general language abilities in which subjects are required to generate a word in response to letter cues. We sought to examine the neural correlates of an acute psychotic state induced by ketamine (an analogue of PCP) in healthy volunteers as they performed a verbal fluency task. Methods: Eleven healthy male volunteers (mean age 28 years) received either intravenous ketamine or placebo in a double-blind manner, while performing an overt verbal fluency task. FMRI data were acquired at 1.5 T. Results: During the ketamine infusion, subjects developed acute psychotic symptoms. The fMRI data revealed a main effect of ketamine, as compared to placebo, with increased activity in the anterior cingulate, prefrontal and parietal cortices, insula and basal ganglia. During the verbal fluency task, relative to placebo, ketamine was associated with greater activation in the prefrontal cortices and basal ganglia. Discussion: A ketamine-induced psychotic state was associated with increased activity in a distributed set of cortical and subcortical regions and a significant modulation of task-related activation during verbal fluency. The latter interaction implicates a prefrontal-striatal network that normally mediates executive aspects of language function in the pathophysiology of an acute psychotic state.
A New Look on Neuropsychological and Psychopathological Syndromes as Derived from a "What" versus "How" Taxonomy of Functions: Its Relevance for Dealing with Consciousness
Paloma Enríquez & Ernst Pöppel
Paloma Enríquez (firstname.lastname@example.org)
Departamento de Psicobiología
In the late eighties a new taxonomy for the understanding of neuropsychological deficits was proposed (Pöppel, 1988, 1989). This taxonomy distinguished two broad kinds of brain functions, from which two distinct categories of neuropsychological disturbances (depending on their aetiological origin) were derived: They were referred to as 'what' and 'how' functions.
'What functions' refer to specific located psychological functions. This approach corresponds to the usual cartographic neuropsychological view, grounded on the classical localisationist perspective. By contrast, 'How functions' refer to more dynamic logistical (less or not located) brain functions which support the specific 'what' activity. This critical kind of brain functions has been neglected as a separate functional domain from a more classical perspective on neuropsychology prevailing even today.
The 'What/How' taxonomy, and specifically the focus on the now re-identified 'How functions' suggests a new and conciliate look on several fields usually treated from very distinct perspectives, allowing to conceive challenging new ways towards a possible future integration between them:
1. Direct applications to neuropsychological deficits.
2. New applications to psychopathological syndromes, as for instance those involving dissociative disturbances.
3. Main derivations for dealing with some of the core (and yet unsolved) problems of psychology and neuroscience, as that of consciousness.
Science of consciousness
A new wave of brain imaging evidence fits novel predictions from global workspace theory: The conscious access hypothesis
Bernard J. Baars
Bernard J. Baars (email@example.com / firstname.lastname@example.org)
The Neurosciences Institute
10640 John Jay Hopkins Drive
San Diego 92121, USA
Consciousness may help mobilize and integrate brain functions that are otherwise separate and independent. Evidence for this 'conscious access hypothesis' was described almost two decades ago, in a framework called global workspace theory (Baars, 1988, 2002). Recent neuroimaging evidence from different laboratories using different methods to compare conscious vs. unconscious sensory input, appears to support the hypothesis (e.g. Dehaene et al, 2001). The methods include visual backward masking, inattentional blindness, change blindness, neglect, extinction, sleep-waking, repetition priming, etc. Versions of the hypothesis are now supported by philosophers like Daniel Dennett and Ned Block, and by some cognitive and neuroscientists.
If consciousness implies global access in the brain it may be needed for any process that is not completely predictable. It therefore has implications for perception, learning, working memory, voluntary control, attention, and self
systems in the brain. Gamma synchrony in the thalamocortical complex may facilitate conscious access.
Baars, B.J. (1988) A cognitive theory of consciousness. Cambridge University Press. Also at www.nsi.edu/users/baars.
Baars, B.J. (2002) The conscious access hypothesis: Origins and recent evidence. Trends in Cognitive Sciences, Jan., 6 (1). Also at www.nsi.edu/users/baars.
Dehaene, S. et al (2001) Cerebral mechanisms of word masking and unconscious repetition priming. Nature Neuroscience, 4, 752-758.
What IDA says about conscious and unconscious language processing and verbal reports
Stan Franklin (email@example.com)
University of Memphis
Memphis, TN, 38152
A conceptual and computational model of consciousness provides its answers to questions of the relationship between consciousness and verbal report, of the role of verbal reports in the scientific study of consciousness, and of the characteristics of conscious and unconsciousness processing of language. In the IDA model, a complex software agent based on Baars¹ global workspace theory, incoming language is processed unconsciously by the perception module prior to selected derived meanings coming to consciousness. Computational mechanisms for both perception and consciousness, and their interaction, will be described, providing hypotheses about the characteristics of unconscious vs. conscious processing. There is currently no provision for verbal reports in the model. However, adding it conceptually or computationally would present no difficulty. Existing mechanisms within the model will suffice. Consciousness would work perfectly well with or without verbal report. IDA¹s understanding and generation of language, while real, is rudimentary by human standards due to her narrow domain. As a result, the model should prove useful as an extreme case in the study of the relationship between consciousness and language. Researchers can see what relations hold even in a relatively primitive system.
Searching for a unified science of consciousness
Antti Revonsuo (firstname.lastname@example.org)
Department of Philosophy, Center for Cognitive Neuroscience
University of Turku
If the diverse studies on consciousness are supposed to develop into coherent science, then we should expect a unified research program to emerge at some point. The unified research program should define a set of widely shared background assumptions that guide both empirical and theoretical research, and it should give a clear and empirically plausible answer to the philosophical questions concerning the place of consciousness in nature (Revonsuo 2000). My suggestion for the core assumptions of a unified research program is Biological Realism or treating consciousness as a biological phenomenon. This basic assumption implies that the explanation of consciousness should be done within a biological framework. Recent advances in the philosophy of neuroscience indicate that to explain a particular biological phenomenon involves tracing the different dimensions in a causal-mechanical network surrounding the phenomenon. This biological explanatory framework greatly clarifies what it really means to "explain" consciousness: it turns out that the explanation of consciousness consists of several different dimensions of explanation, and different sorts of questions and evidence are relevant for illuminating each of these explanatory dimensions. The biological framework also illuminates in a new way the nature of the central research problems in consciousness studies (e.g. the neural correlates of consciousness [Revonsuo 2001], the binding problem [Revonsuo 1999]), and could eventually lead to a unified research program on consciousness.
Revonsuo A (1999) Binding and the phenomenal unity of consciousness. Consciousness and Cognition 8(2), 173-185.
Revonsuo A (2000) Prospects for a scientific research program on consciousness. In: Metzinger T (Ed.) Neural Correlates of Consciousness, 57-75. Cambridge, MA: MIT Press.
Revonsuo A (2001) Can functional brain imaging discover consciousness in the brain? Journal of Consciousness Studies 8 (3): 3-23.
Consciousness and Revolution
Language of Thought
The language of conscious thought
Antoni Gomila (email@example.com)
Univ. Balearic Islands
07071 Palma de Mallorca (Spain)
There is a growing consensus in Cognitive Science in establishing a dual view of cognition; one that distinguishes between either implicit and explicit processes, or automatic and controlled, or associative and rule-based. There are plenty of varieties of this view, which was much encouraged by the success of the notion of modularity.
I want to explore to what extent this dual view of cognition coincides with the distinction between unconscious and conscious processes, and to what extent language acquisition can be thought of as the key developmental process in giving rise to the duality of processes. My contention is that the difference between these two sorts of processes is representational, rejecting the view that what makes a mental state conscious is different from what characterizes it functionally.
I will present, first, a range of dual theories of basic processes (attention, perception, memory, learning, reasoning); second, I will show that neither of the pairs of opposite processes can be seen as exclussive and exhaustive, since in development, what is implicit can become explicit, what is controlled can become automatic (through practice), what is associative can become rule-based, and viceversa. Third, I will content that the main reasons for the existence of a language of thought hold only for linguistic minds, thus finding a representational difference between both kinds of processes; and fourth, that linguistic development correlates with development of the executive function, which typically involves awareness.
Structured Representations and Systematic Revision in Conscious Mental Processes
Joe Lau (firstname.lastname@example.org)
Department of Philosophy
The University of Hong Kong
Fodor and Pylyshyn have famously argued that the systematicity of cognition is best explained by postulating structured, mental representations. Many connectionists disagree, and they believe that connectionist networks can exhibit systematicity without invoking structured representations. In this paper I present a new version of the systematicity argument. It is suggested that representations involved in conscious mental processes are subject to systematic manipulation and revision. For example, part of the phenomenology of formulating linguistic intentions and action plans is that they have components that can be modified and replaced easily. This can be readily explained if the representations involved in such processes are indeed classically structured representations. A connectionist alternative might involve representational schemes using for example RAAM, simple recurrent nets, or holographic reduced representations. However, I shall argue that there are various difficulties and inadequacies in employing such schemes to explain systematic revision in a non-classical manner.
Is there any good introspective argument for the language of thought?
Edouard Machery (email@example.com)
Université de Paris-Sorbonne, philosophy dpt
80-82, rue de la Roquette
The language of thought hypothesis (LOTH) claims that thoughts are complex mental representations (MRs) compounded out of simpler MRs (concepts) in a syntactic way. Now the conscious inner speech seems to corroborate partly this thesis. The introspective argument draws on that point (Carruthers, 1996):
- The introspection suggests that our conscious thoughts tokens are subvocalized natural language sentences.
- Barring any cogent objection, we are entitled to trust the outcome of introspection.
- There are no cogent objections.
- Hence, conscious thoughts are subvocalized natural language sentences.
- Hence, LOTH is at least true of the conscious thought, though it does not require any mentalese.
This paper claims that at least when the truth of LOTH is in question, the introspection cannot be justifiably trusted : hence the crucial premise 2. is wanting. Our objection consists of two theses:
A/ LOTH concerns the vehicles of our thoughts.
B/ We don't have any introspective access to the properties of the vehicles of our thoughts.
This paper argues for both theses and responds to a possible argument against B/ :
/ The forms of inner speech sentences causally drive the reasoning.
/ We have an introspective access to these forms.
/ Only properties of the vehicles of our MRs are causally efficient.
Compositionality and Introspection
Markus Werning (firstname.lastname@example.org)
The opinions that introspective thoughts are possible and that thought is semantically compositional, the paper argues, can only be reconciled if we assume that introspective thoughts are formed in a language that combines symbolic elements from expressible sub-symbolic elements.
Since an introspective thought reports another thought, it should be understood analogous to the report of a sentence by another sentence, i.e., as quotation. There are two options to analyze quotation. The first option postulates the rule: If p is a well-formed symbol of the language, then 'p' is a well-formed symbol of the language and the meaning of 'p' is p. This option, it is shown, violates the principle that the meaning of a syntactically complex symbol is determined by the meanings of its syntactic parts and the syntactic rule by which the parts are combined. The second option treats quotations as concatenations from a finite set of sub-symbolic elements. This option is consistent with compositionality, but requires that sub-symbolic elements are expressible in the language.
Unlike formal languages and Mentalese, natural languages do build symbolic elements, i.e., morphemes, from expressible sub-symbolic elements, i.e., phonemes. It is concluded that introspective thoughts necessarily are formed in (imagined) natural (i.e. phonetic) language.
A Home for Wayward HOTs
Jared Blank (email@example.com)
769 Greenwich Street
New York, New York 10014
I intend to defend the Higher Order Thought (HOT) theory of consciousness, advocated by Rosenthal, from its most damaging criticism: the Wayward HOTs Objection. A principle explanatory virtue of the HOT theory is that it analyzes consciousness in terms of a semantic relation between HOTs and their targets. A mental state is conscious, according to the theory, when one is in a higher order state the content of which is just that one is in the target state. The character of the conscious experience, though, is determined by the representational content of the HOT even when the HOT is wayward or misrepresents the target state. Given wayward HOTs power to determine one's conscious experience, the explanatory relevance of the relation between HOTs and their targets has been questioned; if HOTs determine the character of conscious experience when they misrepresent their target states then the general explanatory function of the target states seems to be rendered impotent. Though I show how Rosenthal's response to this criticism is inadequate, certain aspects of it prove to be instructive: I demonstrate how they point the way towards a proper understanding of the relation between HOTs and their targets and so to a resolution of this criticism.
Self-Ascription and Co-Consciousness: A Neo-Kantian view
Alan Thomas (firstname.lastname@example.org)
Department of Philosophy
University of Kent at Canterbury
Canterbury, Kent, CT2 7NF
This paper explains our capacity to self-ascribe our mental states and the unity of consciousness expressed by the exercise of such a capacity. Shoemaker has argued that a functionalistically describable subject "self-tokens" its first-order beliefs, via reliably functioning cognitive mechanisms, so as to meet a defensible co-consciousness requirement. This paper develops a rival view (more radically Kantian). Kant offers a tri-partite account of consciousness: an adverbial theory of first order consciousness, an account of the necessity of self-ascription, and an account of self-consciousness as clearly distinct from the other two phenomena. The perspectival character of first order conscious experience is the basis of a capacity to self-ascribe conscious mental states that shows, but does not say, the unity of the conscious mental life of that subject. This avoids an important problem for higher order theories of consciousness: the fact that our conscious mental lives are unified is shown by the exercise of a capacity for self-ascription that can be deployed by a subject who does not possess the concepts of a self, or of mental kinds. Thus, an account can be given of the unity of the self that avoids crediting a conscious subject with a concept of itself that makes the account circular. Overall, the paper serves to undermine the idea that a mental state is conscious if it is in some way "targeted" by an inner analogue of the intentionality of those states that are directed "outwards".
Wine, Words, and What It's Like
Josh Weisberg (email@example.com)
236 Dekalb Ave.
In the course of learning the art of wine tasting, one acquires a variety of new words for picking out subtle variations in the taste of wine. Words like "flinty" "tannic" and "peppery" are taught to the novice, who then learns to categorize wines appropriately. Arguably, learning these words, and the mental concepts that they express, actually influences what it is like to consciously experience the rich gustatory sensations of the wine. Prior to acquiring the concepts, the wine tastes one way; afterwards, the experience is different.
David M. Rosenthal (1997, forthcoming) has argued that wine tasting, and related cases, provide a degree of support for the "higher-order-thought" (HOT) hypothesis of mental state consciousness. In this presentation, I will explore this claim, and consider if there are viable competing explanations of the cases. I will also investigate the close connection between consciousness and the learning of words and concepts, from the perspective of the HOT theory.
Rosenthal, David M. (1997) "Apperception, Sensation, and Dissociability," Mind and Language 12, 2 (June): 206-223.
Rosenthal, David M. (forthcoming) "Explaining Consciousness," in Philosophy of Mind: Classical and Contemporary Readings, ed. David J. Chalmers, New York: Oxford University Press, 2002.
The Self-Consciousness of Consciousness: Conceptual Convergence and Clues to an Ontology
Kenneth W. Williford (firstname.lastname@example.org)
Department of Philosophy
The University of Iowa
Iowa City, IA 52242 USA
The claim that all consciousness is self-consciousness is typically met with a number of important objections. Doesn't the claim lead to an infinite regress? Doesn't it seem phenomenologically inaccurate: surely we can think of objects other than ourselves? What about infants and animals lacking a "self-concept"? What about long-distance truck driving? What about unconscious mental processing? The present paper seeks to obviate some of and accommodate the rest of these objections by recovering, clarifying (both phenomenologically and conceptually), and defending a version of the thesis that has largely been forgotten, viz., that all consciousness is implicit, marginal, tacit, or non-positional consciousness of itself. The thesis, articulated notably by Sartre, Merleau-Ponty, and Gurwitsch, has more recently been defended by David Woodruff Smith and Tomis Kapitan. I distinguish the thesis from its relatives, so-called "higher-order thoughts" theories of consciousness, and note some of its advantages. In particular, I argue that a proper understanding of the thesis leads to the following: 1) A unification of many apparently disparate descriptions of consciousness found in theorists as different as Douglas Hofstadter, Antonio Damasio, et al. 2) A clarification of the often misunderstood relation between the constant, implicit reflexivity of consciousness and the sporadic, explicit reflectivity manifest in thoughts that employ a robust concept of the self. 3) A unification of phenomenological work on consciousness with work inspired by the logic of self-reference (e.g., Hofstadter,Perlis, Bojadziev), along with an articulation of a phenomenological method that stresses the importance of the formal features of consciousness as opposed to its overly emphasized qualitative ones. 4) An indication of vital clues to the solution of several outstanding problems in the theory of consciousness: qualia, the semantic determinacy of thought!, the unity of consciousness, the capacity for reflection, volitional causation, and the hard problem itself.
Neuromagnetic correlates of perceptual convergence in primary visual cortex
John-Dylan Haynes, Gerhard Roth, Michael Stadler & Hans-Jochen Heinze
John-Dylan Haynes (email@example.com)
c/o Abteilung fuer Neuropsychologie
Grazer Str. 6
28334 Bremen / Germany
Among the various experimental paradigms that can be interpreted within the framework of neural correlates of consciousness one has unjustly received little attention:
"Perceptual convergence" refers to experiments designed to track at which stage visual processing of stimuli that are physically different but are perceived to be identical converges. This is complementary to the "perceptual divergence" approach as in multistable perception where a single stimulus can lead to alternation between several interpretations. Here we demonstrate that perceptual convergence for low level features such as contrast may occur as early as primary visual cortex using a combination of EEG and MEG with source localisation. Stimuli with the same physical contrast but very different perceived contrasts due to lateral masking elicit very different responses in primary visual cortex. However stimuli that are psychophysically adjusted to match but have very different physical contrasts evoke highly similar responses in V1, especially at a later feedback stage of processing. This is discussed in the light of recent evidence that primary visual cortex may play a larger role in direct conscious representation of low level visual features than previously thought.
Two Modes of Conscious Visual Perception: Cerebral Sites & Cortical Mechanisms
Shaul Hochstein & Merav Ahissar
Shaul Hochstein (firstname.lastname@example.org)
Institute of Life Sciences
Neural Computation Center
Jerusalem, Israel 91904
We report a new view, dividing conscious perception into two modes: rapid "vision at a glance" and slower "vision with scrutiny". The dichotomy encompasses a wide variety of phenomena, including our ability to perceive complex images even when these are presented at very rapid rates (RSVP) but a surprising inability to note seemingly large changes in flashed pictures (change blindness). We attributes rapid conscious vision with spread attention to the large receptive fields of high-level cortical areas, where neurons respond to complex images but generalize over precise object location, orientation, size, lighting or particular details that originally formed the recognized category. In contrast, slower perception with focused attention is seen as a conscious return to lower cortical levels following reverse-hierarchy feedback connections to the ultimate sources of higher level activation, recovering detailed information available in the specialized receptive fields found there. Indeed, the characteristics of these perceptual modes match those of higher and lower areas, respectively. This dual correspondence is especially apparent in the two modes of visual search: Spread- attention feature search ("what" without "where") derives not from low-level cortical areas as previously assumed, but from higher-level position-insensitive receptive fields. On the other hand, scanning-attention difficult or conjunction search derives from explicit perception's return to low-level position-encoding receptive fields. We present additional perceptual phenomena, backed by physiological data, in support of this novel Reverse Hierarchy Theory. Thus, conscious perception begins at post-hierarchical processing high cortical levels where complex images are perceived with spread attention, and later dips back down in reverse hierarchy fashion to focus attention on specific details represented in low cortical level receptive fields.
Change Detection, Visual Representation, and Consciousness
Douglas B. Meehan
Douglas B. Meehan (email@example.com)
CUNY Graduate Center, Philosophy Program
365 Fifth Ave.
New York, NY 10016-4309...
Change blindness experiments show that subjects are often unaware of significant changes in visual scenes. This suggests that we don't see in as much detail as we believe we do. Kevin O'Regan and Alva Noë (forthcoming) conclude that visual perception doesn't involve detailed picture-like representations, giving an alternative explanation of visual experience in terms of our implicit knowledge of correlations between visual stimulation and eye-movement.
This rejection of visual representations assumes, however, that if they did occur, we would have exhaustive access to them. But we don't have exhaustive access to our perceptual states, as unconscious perception shows. Further, there is evidence that we can detect changes in visual scenes even when we cannot report doing so (Fernandez-Duque and Thornton, 2000).
These considerations suggest, I argue, that we can best explain change blindness not by supposing that there are no visual representations but by recognizing that we sometimes aren't conscious of them. That, in turn, is best explained in terms of a higher-order theory of consciousness (e.g., Rosenthal, 1997). Finally, I explain the nature of the representations involved in visual experience with Sellars' (1956) view that families of mental properties are
homomorphic to families of visible stimulus properties.
Fernandez-Duque and Thornton (2000). Change detection without awareness: Do explicit reports underestimate the representation of change in the visual system. Visual Cognition, 7, 324-344.
O'Regan, Kevin and Noë, Alva (forthcoming). A Sensorimotor Account of Vision and Visual Consciousness. Behavioral and Brain Sciences, 24(5).
Rosenthal, David M. (1997). A Theory of Consciousness. In N. Block, O. Flanagan, G. Güzeldere (Eds.). The Nature of Consciousness. Cambridge: MIT Press.
Sellars, Wilfrid (1956). Empiricism and the Philosophy of Mind. In Science, Perception and Reality. Atascadero: Ridgeview, 1963.
Evidence for a non-continuous transition between conscious and unconscious processing of visual stimuli
Claire Sergent & Stanislas Dehaene
Claire SERGENT (firstname.lastname@example.org)
4, place du General Leclerc
If two targets are to be identified among distractors displayed in rapid sequence, correct identification of the 1st target hinders identification of the 2nd. This phenomenon is called the Attentional Blink. We used in this phenomenon to investigate the nature of the transition between unconscious and conscious processing of visual stimuli.
We asked participants to evaluate the visibility degree of the 2nd target on a continuous scale. There were two main conditions : a condition in which identification of the 1st target was required ("dual task") which produced an attentional blink on the 2nd target, and a condition in which no identification of the 1st target was required ("single task") producing no impairment on the 2nd target. In both conditions, the target was absent in half of the trials.
During the attentional blink (dual task), participants used the continuous scale in a bimodal way : they mainly used the higher or the lower visibility degrees and hardly ever used intermediate visibility. A multiple regression on this pattern of response revealed that it was a combination of the patterns obtained when the 2nd target was absent and when it was present and easily detected (single task).
These results suggest that, during the attentional blink, the 2nd target is either perfectly identified or not detected at all. Thus, unconscious processing obtained by manipulation of attention would be better discribed as an alternative to the conscious processing than as an impoverishment of the conscious processing.
Consciousness, Inner Speech & Language
Garry Briscoe (email@example.com)
Computer Science Department
University of Wisconsin Oshkosh
800 Algoma Blvd.,
Oshkosh, Wisconsin, 54901, USA
While some contend that language is important for higher states of consciousness, this presentation proposes that it is not language per se that is essential, but rather inner speech, our ability to converse with ourselves.
The traditional view of language holds that external speech sounds are processed within Wernicke's area in the left posterior temporal cortex, where composite words are recognized. This model further proposes that language signals then travel to Broca's area in the left inferior frontal lobe where expressive language is encoded into articulatory form. Recently, however, this view of language has come under challenge as researchers, using mainly imaging techniques, have noted language tasks that seem to involve cortical regions outside of those associated with the classical models.
A new neural model of cortical processing will be outlined in which streams of neural activations enter the system at primary sensory areas, and proceed through association and frontal areas. These flows are multiply recurrent, and so represent a highly dynamic system. The majority of flows are concerned with unconscious bodily behaviors, and involve the learning of perceptual (nameless) concepts that link external sensory inputs with corresponding learned motor behaviors; in other words, learned skills.
The language component of the proposed model extends that of the classical theory, suggesting that multiple areas of the cortex are involved in the processing of language. For example, it is now known that flows along the superior temporal cortex are involved in speech recognition. The model proposes that the function of the temporal cortex is that of a differentiation device, allowing sounds to be recognized as particular words. Recurrently linked self-organizing maps allow just such an interpretation.
The model proposes that incoming auditory inputs are divided into essentially two streams (as is supported by recent experimental results), one stream traveling along the superior temporal lobe, and the second traveling through the insular region to the frontal lobe. It is this second flow that forms the major component of inner speech. Recurrent linkages from Broca's area back to Wernicke's area allow for the generation of internally-generated pseudo-sound sequences that form inner speech. In other words, a part of the cortex (Broca's area) that is adjacent to motor areas responsible for expressive speech, is able to generate internal speech that travels directly to auditory input areas rather than travel through the external medium of the environment. A similar proposal for the visual modality allows for inner signing.
The presentation will describe primary consciousness as resulting from neural flows not involved with inner speech. This form of consciousness is shared by other animals, and involves being awake and alert, and being able to link sensory inputs with connected motor outputs.
Inner speech, however, forms a major part of the experience of consciousness for humans, and this additional component of consciousness is termed secondary consciousness. Inner speech allows us to bifurcate the world into multifaceted concepts, and provides a mechanism for direct inner awareness. Without inner speech, conscious experience is greatly reduced, and several neurological deficits (such as blindsight) will be used to illustrate this point.
The Statistical Brain: Reply to Marcus' The Algebraic Mind
Francisco Calvo Garzón
Francisco Calvo Garzón (firstname.lastname@example.org)
Departamento de Filosofía
Edificio Luis Vives
Universidad de Murcia
E-30100 Murcia (Spain)
Gary Marcus (The Algebraic Mind, Cambridge, Mass.: MIT Press, 2001) distinguishes two separate ontologies in the connectionist realm: implementational connectionism and eliminative connectionism. The former accounts for cognitive phenomena by positing sets of explicit rules that serve the purpose of symbolic manipulation. The latter, in terms of computational abilities which are the result of an associative memory. Marcus argues that the connectionist models which preserve their computational equivalency with respect to classical ones are those that implement classical rules. In this notice, I shall offer a three-fold reply to Marcus: First, (i) I shall argue that he does not provide a robust criterion to decide when a network implements a rule. Second, (ii) I'll argue that his proposal to implement recursive combinations by means of encodings where tokens that belong to the same representational type are identical lacks biological plausibility. And finally, (iii) I'll argue that even if points (i) and (ii) were wrong, the neural substrate may impose limitations on the mechanisms that permit the system carry out the appropriate computations. These limitations may tip the balance in favour of a (biologically plausible) Hebbian arquitecture. I shall conclude that Marcus fails in his attempt to override eliminative connectionism.
Automaticity of Semantic Processing on a Sentence Level
Dana Ganor & Joseph Tzelgov
Dana Ganor (email@example.com)
Dept. of Behavioral Sciences
Ben Gurion University of the Negev
Beer Sheva, Israel 84105
Tzelgov's (1997) definition of automatic processing as being processing that takes place although it is not part of a task requirement, was used as a basis for investigating automaticity of semantic processing on a sentence level. In the first series of studies the effect of type of experimental task on the conditions under which the automatic process would take place was investigated. Will automatic processing occur only when the experimental task triggers it? To study automatic semantic processing, the type of experimental task was varied from one which involves a process similar to semantic processing (i.e., syntactic processing), to one that involves a linguistic process on a lexical level, and to one that involves a non-linguistic process (i.e., font judgment). Under all three tasks evidence was found for automatic semantic processing. The second series of studies examined whether automatic semantic processing took place when sentences were not well formed (i.e., containing grammatical errors or presented in a scrambled order). It was found that subjects extracted meaning from sentences that were poorly constructed even though they were not asked to do so. The results suggest that semantic processing of sentences occurs automatically, regardless of experimental task and the quality of presented material.
Time and space in phoneme perception
Kei Omata & Ken Mogi
Ken Mogi (firstname.lastname@example.org)
Takanawa Muse Bldg.
Shinagawa-ku, Tokyo, 141-0022 Japan
Phoneme perception is an important step in language cognition. The McGurk effect (McGurk & MacDonald 1976), where a simultaneous presentation of incompatible visual and auditory stimuli leads to a misperception of phonemes, demonstrates that audiovisual integration plays an essential role in phoneme perception. Here, we report a series of psychophysical experiments aimed at elucidating the spatio-temporal constraints involved in the integration process. Using modern technologies, incompatible visual and auditory stimuli were presented with various timing and localization
conditions. Presentation of the visual and auditory stimuli in the right egocentric field resulted in a stronger McGurk type effect, possibly related to the left hemisphere dominance of language processing. The effect of the proximity of audio and visual stimuli also exhibited a marked lateral asymmetry. Taking into account the results on the effect of timing in experiments of our own and others (e.g. Munhall et al.1996), we construct a model of the spatio-temporal ?streamlining? involved in the integration process. Our model puts phoneme perception within the context of the more general neural mechanisms of multimodal integration, with a particular emphasis on the relation to the egocentric spatio-temporal
perception, such as body image.
Reflective consciousness and intentionality
Lisa Bortolotti (email@example.com)
Philosophy Program RSSS
Coombs Building ANU
ACT 0200 Canberra
According to Davidson, one can be a believer only if one has the concept of 'belief' and is able to recognise oneself and others as believers. These requirements are often tied to the presence of reflective consciousness and linguistic abilities. In the literature on animal cognition there is scepticism about non-human animals (even primates and dolphins) being reflectively conscious and viewing themselves and others as intentional systems. Thus, Davidson's view seems to imply that non-human animals cannot entertain beliefs. In Rational Animals (1982) and The Emergence of Thought (1997), he explicitly denies that non-human animals and human infants can be believers. I find this consequence of Davidson's requirements on belief possession implausible and I suggest an alternative view. Suppose we construe a minimal account of belief, where beliefs are simply mental states with content that are formed on the basis of some evidence, can be revised on the basis of some other evidence and can be acted upon. Then perceptual consciousness, but not reflective consciousness, seems to be necessary for a creature to be a believer.The requirements for rational believers, instead, require the capacity of the creature to critically examine her own mental states, evaluate evidence and aim at consistency and coherence. This is the kind of cognitive achievement that seems precluded to most non-human animals. My suggestion has one clear advantage over Davidson's. It allows us to see continuity between human and non-human animal cognition and to describe non-human animals as intentional systems when they categorise, learn and communicate.
Content and Infant Consciousness
Sarah E. Clegg
Sarah Eleanor Clegg (firstname.lastname@example.org)
Department of Philosophy
University of Sheffield, Western Bank
Sheffield, S10 2TN
In recent years representational theories of phenomenal consciousness have grown in both popularity and number. Among these theories are the much discussed higher-order thought (HOT) theories which state that a mental state is conscious just in case it is, or is disposed to be, targeted by a higher-order thought about itself. One of the most common objections levelled against such theories (e.g. Dretske 1995) is that they exclude infants and autistic individuals. In this paper I argue that the objection can be answered, but that doing so depends on both the account of content and on the version of HOT theory adopted. In particular, I outline how adopting a teleosemantic theory of intentional content will allow *dispositional* higher-order thought theories to escape from this objection. Such an account of intentional content, allows us to show that an infant's experiences are phenomenally conscious in virtue of their function. I argue that, given a normal development, the function of the infant's perceptual experiences is to feed into higher-order thoughts about themselves regardless of whether the relevant higher-order systems are in place. In the same way, I shall argue that autistic people will also be phenomenally conscious according to Dispositional HOT theory.
Language and Theory-of-Mind Development: 4-Year-Old Spanish Children's Linguistic Abilities in the Understanding of False Belief
Belén Pascual, Jaime Nubiola, Gerardo Aguado & María Sotillo
Belén Pascual (email@example.com)
Universidad de Navarra
The main period of theory-of-mind development, the ability to seeing oneself and others in terms of mental states (beliefs, desires, intentions, imagination, emotions, and so on), is also the major period of language acquisition, from 2- to 5-year-olds. Studies of thought and language in child development are usually focused on two fields: 1) the capacity of children to represent false-beliefs, and 2) their linguistic abilities that provide the representational format needed to understand false-belief, including the contributions of syntax and semantics.
The present study explores the relationship between natural language production and the classic false-belief task performance in a sample of twenty-five children between 3;11 and 4;2-year-old. The natural language, transcribed and analyzed using CHAT codes and CLAN programs provided by the CHILDES Project (MacWhinney, 1995), was assessed according to four focal components: mean length of utterance (MLU), syntactic complexity, grammatical form of sentences with mental verbs and the frequency of their occurrence. Findings are consistent with the claim that language is fundamental to theory-of-mind development (Astington & Jenkins, 1999; Segal, 1998; de Villiers, 2000; Zelazo, 1999).
Rationality and Access Consciousness
Matteo Mameli (firstname.lastname@example.org)
London School of Economics
Dept. of Philosophy, Logic and Scientific Method
Houghton Street, London WC2A 2AE
Is access consciousness necessary for (theoretical or practical) rationality? Does one need to be able to register one's own mental states in order to be rational? Does rationality require the ability to represent to oneself the contents of one's own thoughts? Does it require the ability to report to others the contents of one's own thoughts? The answers to these questions depend on what one means by 'rationality'. I argue that there are at least two distinct theoretical roles that 'rationality' plays in discussions about the correctness of thought and behaviour. That is, there are at least two distinct concepts of rationality. If one is thinking about rationality in terms of one of these two concepts, then it can be shown that access consciousness and reportability are not required for rational thought and behaviour, and that, in some cases and for some tasks, one can be more rational by not having access consciousness or by not using it. In contrast, if one is thinking about rationality in terms of the other concept, then access consciousness becomes an essential feature of rationality, and reportability (in case this is distinct from access consciousness) becomes a tool for being more rational.
Why are some verbal-like thoughts amenable to consciousness?
Benny SHANON (email@example.com)
Department of Psychology
The Hebrew University
The relationship between consciousness, thought processes and language is examined on the basis of the analysis of thought sequences, that is - trains of verbal-like expressions that spontaneously pass through people's heads. A large corpus of such sequences was collected and subject to various structural analyses. In this presentation, I consider the possible functional advantages of the conscious experience of thought sequences. I propose that such an experience affords mentation with a quality of rawness analogous to that associated with perception. This entails three functional benefits. First, rawness allows for non-fixedness in terms of prior codification, and thus affords fluidity in the progression of thinking and hence potential cognitive novelty. Second, rawness provides a medium that makes the thinking process akin to action in the real world. In this fashion, consciousness may be viewed as affording a virtual reality in which cognitive agents may act when concrete action in the real world is not feasible. Third, verbal-like articulation results in objectivization that provides compartmentalization of thought and serves as the basis for further reflection. While the present discussion is based primarily on the analysis of verbal-like expressions, it is pointed out that analogous patterns are encountered in other domains of cognitive activity. Together, these suggest a new perspective by which the function of consciousness may be considered.
Access consciousness and its phenomenal properties
Finn Spicer (firstname.lastname@example.org)
13 Herbert Crescent
This paper offers a model of how we have authoritative access to consciously held propositional attitudes-an account of what access-consciousness consists in. The account is in terms of an ability one has to token a first-order thought at will (an 'entertaining' of a content), and then (by inner demonstrative) form a demonstrative concept which types propositional attitudes according to content (Fregean sense). The ability to entertain a thought at will is described as a product of the language faculty, and is close to what is known as 'inner speech'. Like inner speech, an entertaining of a content has phenomenal-conscious properties; hence this account offers an explanation of why certain phenomenal properties attach to access- consciousness propositional attitudes.
Impaired implicit cognition following frontal brain injury
Lynne Barker & Jackie Andrade
Jackie Andrade (email@example.com)
Dept of Psychology
University of Sheffield
Sheffield S10 2TP, UK
Frontal brain injury is associated with deficits in conscious cognition such as planning, sustained attention, decision making. Marked changes in personality, emotional lability and social behaviour are also seen. Theoretical accounts that emphasise disorders of controlled attention and goal-directed behaviour give little insight into these more socially-mediated aspects of the disorder. We hypothesised that deficits in implicit cognition may contribute to behavioural changes manifested after frontal damage. We tested 15 people with frontal brain injury on a battery of tests including the WAIS, WMS and BADS, the latter giving measures of executive function. We compared their performance with that of 14 age- and IQ-matched controls on two tests of implicit cognition: a serial reaction time task (SRTT) and an implicit memory task that measured the mere exposure effect as an increase in preference for previously presented non-words. The control group showed significant learning on the SRTT (p < .001) and a mere exposure effect (p < .03). Frontal patients showed no evidence of learning on the SRTT and no effect of exposure to the non-words (p > .10). We will discuss the relationship between these impairments in implicit cognition and patients' problems with social behaviour and explicit cognition.
Evidence for unconscious learning during anaesthesia
Catherine Hanna & Jackie Andrade
Catherine Hanna (firstname.lastname@example.org)
University of Sheffield
Department of Psychology
Sheffield, S10 2TP UK
Studies of learning during general anaesthesia have produced mixed results. One explanation of the findings is that learning occurs only during light anaesthesia, and may not be truly unconscious. We suggested an alternative explanation (1), that surgery facilitates implicit learning during anaesthesia through the release of stress hormones. We tested this prediction by presenting words either during steady-state anaesthesia before surgery, or during surgery. Word stem completion scores showed implicit memory for patients receiving the words during surgery but not for those receiving the words before surgery. There was no evidence of explicit memory. Clinical measures and bispectral index (EEG) recordings indicated equally deep anaesthesia in both groups. The mean bispectral index score was 42, indicating deep anaesthesia. However, a post-hoc analysis of the surgery group showed implicit memory only for those patients with bispectral index scores exceeding 40 during word presentation. Patients received no neuromuscular blockers, and so were free to move or open their eyes if they became conscious. None did so. We therefore conclude that unconscious learning does occur during general anaesthesia, but only when the anaesthetic is relatively light and when there is a stress response caused by surgery or other stimulus.
1. Andrade J, Englert L, Harper C, Edwards ND: Comparing the effects of stimulation and propofol infusion rate on implicit and explicit memory formation. British Journal of Anaesthesia 2001; 86: 189-95
'Fringe consciousness' and intuitions: Empirical investigations
Elisabeth Norman & Mark C. Price
Elisabeth Norman (Elisabeth.Norman@psysp.uib.no)
Institutt for Samfunnspsykologi, UiB
Fringe consciousness has been proposed as a specific class of conscious experience (Mangan, 2001). 'Fringe' feelings or intuitions are said to include tip-of-the-tongue states, feelings of knowing, feelings of familiarity and feelings of rightness/wrongness. Mangan proposes that fringe consciousness reflects unconscious knowledge which is relevant to the current contents of conscious awareness but which would exceed the limited capacity of consciousness if brought into awareness (Mangan, 1993). If fringe consciousness provides a mechanism for monitoring and controlling large amounts of information to which attention could potentially be re-directed, it might play a role in a number of cognitive processes.
Empirical investigations of the nature and role of fringe consciousness require an operationalization that includes both phenomenological and behavioural criteria and that allows fringe consciousness to be measured within existing paradigms of implicit cognition. We suggest the following operationalization of fringe consciousness: (a) the presence of a subjectively experienced `feeling' that can be reported by the subject, (b) correlation between this feeling and implicitly guided behaviour, (c) dissociation between the subjectively experienced feeling and conscious access to the implicit knowledge on which the feeling is based, but (d) global accessibility to the subjective feeling, allowing it to be used flexibly to direct behaviour in a controlled manner. We report empirical work which assesses the occurrence of fringe consciousness within an implicit learning paradigm.
Contextual Cueing of Visuo-Spatial Attention: Direct and Indirect Measures of Learning
Robert A.P. Reuter & Axel Cleeremans
Robert A.P. Reuter (email@example.com)
Cognitive Science Research Unit
ULB - CP 191 - Av. F.D. Roosevelt, 50
1050 Brussels, Belgium
Chun and colleagues (Chun et al. 1998, 1999; Chun, 2000) have repeatedly shown that visuo-spatial attention can be guided by implicit top-down visual knowledge. In a visual search task Ss have indeed be shown to make efficient use of global contexts (the spatial layout of distractor items) to detect a specific target stimulus. Visual search RTs are thus faster when Ss respond to targets imbedded in invariant visual configurations than in variable configurations. ŒContextual cueing effects¹ have been observed despite poor explicit recognition performance. In the present study we present a replication of the contextual cueing effect with more heterogeneously distributed distractor configurations. In opposition with Chun et al.¹s studies, our results suggest that in an explicit recognition task (1) Ss can discriminate between invariant and variant visual configurations, but also that (2) they generally claim to be guessing. These results are discussed in the context of ongoing controversy about the extent to which learning can be implicit.
Could synaesthesia be the rule?
Erik Myin (firstname.lastname@example.org)
Centre for Logic and Philosophy of Science
Vrije Universiteit Brussel
Pleinlaan 2, B1050 Brussel, BELGIUM
In a passage in the 'Phenomenology of Perception', Merleau-Ponty states that "synaesthetic perception is the rule". This seems to run counter to the received psychological and neurophysiological models of synesthesia, in which it is seen as an abnormal and arbitrary association between the end products of modality specific input processing streams that are normally kept segregated.
In this presentation, it will be argued that the idea of "synaesthetic perception as the rule" is quite sensible, and that it receives considerable support from the recently proposed 'sensorimotor contingency theory' of vision and visual awareness (O'Regan and Noë, Behavioral and Brain Sciences 2001; Myin & O'Regan, Journal of Consciousness Studies 2002).
The sensorimotor contingency theory shares Merleau-Ponty's fundamental skill theoretic perspective according to which perceptual content is constituted by implicit knowledge about further potential for action offered by the perceived situation, rather than by internal qualities that necessarily have an arbitrary relation with respect to their external stimuli. As perceptual quality then is thought of in terms of bodily determined potential for action, it becomes 'synaesthetic' from the start. Moreover, as some kinds of potential for action are specific for specific senses , this approach provides a natural explanation for the modalities. Yet it also offers a natural explanation for why perceptual content easily becomes synaesthestic in the broader sense that, for example, one can "see the brittleness of a glass". It will be argued that the sensorimotor approach also is able to give a plausible account of the more extreme forms of synaesthesia that have proved so puzzling for traditional theories.
Unconscious Imagery - impossible?
Verena Gottschling (email@example.com)
University of Mainz
I argue that there are problems concerning consciousness and visual mental imagery that neither of the main proponents is aware of. Usually imagery is seen as a conscious cognitive process. All recent empirical possibilities (psychological and neuropsychological findings) we know to examine whether mental imagery takes place, contain necessarily reportability of imagery. And reportability requires conscious experience. My claim is that the possibility of unconscious Imagery is excluded methodically. Unconscious Imagery is theoretically possible but cannot be testet empirically, because imagery is not dissociable from conscious experience of imagining. The recent research program on imagery is restricted to conscious imagery. In Pylyshyn's descriptionalism the main explanandum is tacit knowledge, that is unconscious knowledge represented in propositions. With tacit knowledge we simulate in imagery the corresponding perceptual situation and "produce" the empirical findings. I argue that the explanatory power of this approach is low. With unconscious hidden knowledge you can explain almost every finding. Especially we get no explanation why imagery is conscious. Kosslyn's pictoralism has the same problem: He states conscious imagination takes place in the early vision system - but he cannot explain convincingly why imagery is conscious while early vision is not. A satisfying theory of mental imagery has to include an explanation, (1) of the relationship of imagery and consciousness and their neurological basis (2) if there is unconscious imagery, we need to investigate it. This means a well-defined research program different from the one we have now. All recent approaches do not face these challenges.
Conscious and unconscious processes in craving
Jon May, Jackie Andrade, Nathalie Panabokke & David Kavanagh
Jon May (firstname.lastname@example.org)
Dept of Psychology
University of Sheffield
UK - S10 2TP
Craving is accepted as a key subjective experience leading to substance use and abuse, and as instrumental in relapse from abstinence. Theorists see it as reflecting underlying physiology, or conditioned learning. In contrast, we propose that craving has a causative role in behaviour, and that understanding the conscious and unconscious processes that underpin craving episodes can help in designing interventions to prevent substance use and relapse from abstinence.
A central aspect of our model is the construction of mental images concerning the craved substance. To test this, we asked 20 smokers to abstain for 14 hours, matched with 20 who were allowed to smoke ad lib. All were asked to construct mental images in response to written cues: half constructing visual and half auditory images. Both groups of abstainers reported high craving compared to the smokers before the imagery intervention began. The auditory abstainers continued to report high levels of craving throughout the study, while the visual abstainers reported a sharp decrease in craving as soon as the imagery began. The decrease lasted throughout the study.
This supports our suggestion that visual imagery is central to craving, and in fact that conscious activity is causative. Interfering with a specific conscious content (visual imagery) may be effective in controlling an unconsciously invoked experience (craving).
Pain and Verbal Report
C. Richard Chapman & Ruth Zaslansky
C. Richard Chapman (email@example.com)
Univ of Utah Pain Reseearch Center
615 Arapeen Dr., Suite 200
Salt Lake City, UT 84108
Pain is the most common reason for persons to seek medical services, and yet no objective measures for pain exist. Clinical measurement of pain depends entirely upon introspection and verbal report. It is now completely clear that pain is a complex human experience with sensory, emotional and cognitive aspects; pain is not a primitive sensation. We propose that clinical pain report reflects bodily ill-being, as opposed to well-being, and as such is a negative, multidimensional form of somatic awareness. Pain differs from nociception (non-conscious neural activity invoked by tissue trauma) in several important ways. Moreover, pain can exist in the absence of nociception, and nociception can take place without pain. The most fundamental challenge in pain measurement is to decide what pain actually is and what the pain report should gauge. Current clinical pain measurement practices are fraught with difficulties and inconsistencies. This presentation describes current issues and challenges in pain measurement with case examples and research data.
Mentalism and Introspection: First- or third-person data language?
Donelson E. Dulany
Donelson E. Dulany (firstname.lastname@example.org)
Department of Psychology
University of Illinois
603 East Daniel Street
Champaign, IL 61820
On a mentalistic metatheory (Dulany, 1997), mental episodes consist of conscious states, of modes and contents, interrelated by nonconscious mental operations. Introspective (first-person) reports of conscious states should then be central to a productive mentalistic inquiry. On well-established criteria for data language, however, data assertions are defensible if they meet standards of face validity, or if these are at issue, show reliability over observers given common external experimental events. In first-person (phenomenological) data language, reports refer to conscious states of the observer, which are intrinsically variable within external conditions, thereby excluding the second criterion despite common challenges to the first.
Conscious states can, however, be represented in a phenomenological theory language with first-person reports of those states represented in the experimenter's third-person (physicalistic) data language. Conditions for face validity of reports may then be suggested by the metatheory, with challenges evaluated by a strategy of competitive support, embodying network logic and Bayesian inference. I will sketch a general strategy with illustrative theoretical-experimental analyses of causal inference, with concurrent reports, and of intentional action, with retrospective reports.
Dulany, D.E. (1997). Consciousness in the explicit (deliberative) and implicit (evocative). In J.D. Cohen, & J.W. Schooler
(Eds.) Scientific approaches to consciousness. (pp. 179-211).
Mahwah, NJ: Lawrence Erlbaum Associates, Inc.
Expressing conscious experience in language: What is possible and what is not
Zoltan Jakab (email@example.com)
1922-195 Clearview Avenue
Ottawa, Ontario, K1Z 6S1
As actual reports of some subjects suggest, it seems not possible to explain to someone achromat from birth what it is like to see the colors. Even though currently we do not have a completed knowledge of visual neuroscience, learning what we already have is certainly not enough to teach the congenitally (color) blind the subjective nature of color experience. I shall argue that no description in any language could ever do such a job - hence having completed neuroscience would not help either. This, however, amounts to no argument against physicalism along the lines of Jackson's Mary scenario since I do not claim, indeed, do not believe, that everything that is physical has to be fully expressible in language. I shall argue that color experience, and most other sorts of sensory experience, are not expressible in language because they are too simple, instead of being too complex. Particular color experiences are perceptual states with no constituent structure or a rather minimal one; this prevents us from generating any linguistic description about them that could facilitate the imagination in the unacquainted. On the other hand, perceptual experience that is sufficiently complex can possibly be conveyed to the unacquainted via language, even when at first this seems utterly impossible. This happens, for instance, in the famous case of the chicken sexers explored by Irving Biederman.(1)
NOTE: (1) This topic is closely related to one of the author's papers [Ineffability of qualia: a straightforward naturalistic explanation. Consciousness and Cognition, 9 (3), 329-351, 2000]. My reason for proposing it after publication is that it fits into the topic of the conference (Consciousness and Language), and I wish to have some more feedback on it from the participants.
Qualia, Multiple Realizability and the Identity Thesis
David Hunter (firstname.lastname@example.org)
Buffalo State College, SUNY
1300 Elmwood Avenue
Buffalo, NY 14222 USA
John Perry argues that qualia are identical with non-functional yet causally effective properties of brain states. He offers no specific identities. But the most plausible candidates-such as neural firings or activities-are probably functional states. Moreover, Perry's view resembles Epiphenomenalism: if qualia are not functional, then changes in an agent's qualia need make no difference to what she would notice, say or do. To reply that, while not functionally defined, different qualia in fact play different roles would eliminate an advertised virtue of Perry's view: that unlike Functionalism, it need not explain why qualia play the roles they do. Finally, Perry wrongly assumes that to be multiply realizable qualia must be functional. A given experience occupies a position in an agent's cognitive economy, related to the agent's beliefs, desires and memories. Occupying such a position is not itself a functional property. But it is multiply realizable: a given position could be occupied by different experiences in different agents or times. And to describe an experience's position in such a system would be, in one clear sense, to say what it is like for the agent to have it. My paper develops these points.
Expressing Our Thoughts
William S. Robinson
William S. Robinson (email@example.com)
402 Catt Hall, Iowa State University,
Ames, IA 50011-1306
We have a powerful intuition that (A) our actions express our thoughts. Since this intuition is sometimes mentioned in dismissing epiphenomenalism, "express" in (A) is apparently causal. It is far less plausible to say that (B) our actions are caused by our subvocal speech. I argue that some of the reasons for this lesser plausibility of (B) are generalizable in such a way as to cast doubt on (A), whenever "thoughts" in (A) are regarded as occurrents, whether conscious or not. If, however, the "thoughts" that our actions may express are not conscious occurrents, then it is puzzling how the intuition (A) could seem so compelling. I attempt to unravel this puzzle. The resulting view emphasizes integrative capacities that must underlie cognition, and explains the intuitiveness of (A) as a consequence of those capacities. Since tokenings of sentential representations are occurrents, they will not, on this view, play a fundamental role in explaining thought and action; instead, they will themselves have to be explained by reference to more basic states and mechanisms.
A trilemma regarding spectrum inversion
Pär Sundström (firstname.lastname@example.org)
Dept of Philosophy and Linguistics
SE-903 38 Umeå
In my talk I explore a trilemma for the idea of spectrum inversion: Suppose you and I are the same with respect to how we apply and are disposed to apply a set of predicates (the predicates of interest are such predicates as 'red', 'looks red', 'has the same colour as', 'has the colour it looks to have'). Then it is reasonable to assume that (1) what we say with these predicates is the same. Furthermore, it is reasonable to assume that (2) what we say is what we believe. Now from (1) and (2) one can infer that if you and I are nevertheless inverted with respect to our colour experiences, then at least one of us must be mistaken about what colour things look to that person to have. That is, the unfortunate one of us will believe that an object looks to him to have one colour while in fact it looks to him to have another colour. Anyone who holds that you and I in the described circumstance can be inverted experientially must reject either of (1) or (2), or embrace the consequence. In the talk I explore what the prospects are for taking any of these three routes.
Metaphysics of modality and the failure of reductive explanation
Bettina Walde (Bettina.Walde@lrz.uni-muenchen.de)
Chalmers (1996) argued that we can conceive of scenarios in which physical (functional) isomorphs of human beings lack experience; from the conceivability-implies-possibility-hypothesis it purportedly follows that those scenarios are possible and that materialism must be false. I will argue to the opposite and show (relying on the hypothesis that a priori analyses of macroscopic common sense expressions are not available) that the same kind of modal reasoning may be used to argue that any kind of empirically supported a posteriori necessary identity (or supervenience) statements must be wrong. This result is unacceptable. I will therefore suggest that the metaphysical presuppositions of the modal arguments are flawed. The questionable point seems to be the identification of logical possibility with metaphysical possibility on the level of worlds. I suggest to strictly separate logically possible worlds from metaphysically possible worlds. Metaphysically possible worlds are a subset of logically possible worlds. It is easily shown that denying the alleged identification neither the reductive explanation of the mind-brain nor the reductive explanation of water-H2O is wrong. Modal arguments of the Chalmers variety (under the modified modal space) are strong enough to make an epistemological point but not an ontological one.