Tyler Burge presents an original study of the most primitive ways in which individuals represent the physical world. By reflecting on the science of perception and related psychological and biological sciences, he gives an account of constitutive conditions for perceiving the physical world, and thus aims to locate origins of representational mind.

One of the most important issues concerning the foundations ofconscious perception centerson thequestion of whether perceptual consciousness is rich or sparse. The overflow argument uses a form of ‘iconic memory’ toarguethatperceptual consciousnessisricher (i.e.,has a higher capacity) than cognitive access: when observing a complex scene we are conscious of more than we can report or think about. Recently, the overflow argumenthas been challenged both empirically and conceptually. This paper reviews the controversy, arguing that proponents of sparse perception are committed to the (...) postulation of (i) a peculiar kind of generic conscious representation that has no independent rationale and (ii) an unmotivated form of unconscious representation that in some cases conflicts with what we know about unconscious representation. (shrink)

Block’s well-known distinction between phenomenal consciousness and access consciousness has generated a large philosophical literature about putative conceptual connections between the two. The scientific literature about whether they come apart in any actual cases is rather smaller. Empirical evidence gathered to date has not settled the issue. Some put this down to a fundamental methodological obstacle to the empirical study of the relation between phenomenal consciousness and access consciousness. Block (2007) has drawn attention to the methodological puzzle and attempted to (...) answer it. While the evidence Block points to is relevant and important, this paper puts forward a more systematic framework for addressing the puzzle. To give it a label, the approach is to study phenomenal consciousness as a natural kind. The approach allows consciousness studies to move beyond the initial means of identifying instances of the kind, like verbal report, and to find its underlying nature. It is wellrecognised that facts about an underlying kind may allow identification of instances of the kind that do not match the initial means of identification (cp. non-liquid samples of water). This paper shows that the same method can be deployed to investigate phenomenal consciousness independently of access consciousness. (shrink)

The Oxford Companion to the Mind is a classic. Published in 1987, to huge acclaim, it immediately took its place as the indispensable guide to the mysteries - and idiosyncracies - of the human mind. In no other book can the reader find discussions of concepts such as language, memory, and intelligence, side by side with witty definitions of common human experiences such as the 'cocktail-party' and 'halo' effects, and the least effort principle. Richard Gregory again brings his wit, wisdom, (...) and expertise to bear on this most elusive of subjects. Research into the mind and brain has moved on in bounds in recent years, and interest in the subject has never been so high. There has been a shift in focus away from Freud's concept of the unconscious onto consciousness itself. The new edition of the Companion includes three 'mini symposia' - on consciousness, brain scanning, and artificial intelligence - with contributions from a number of specialists, and encompassing a range of approaches. Cultural as well as scientific in approach, this accessible book offers authoritative descriptions and analysis. With new entries on controversial topics such as artificial life, attachment theory, caffeine, cruetly, drama, extra-terrestrial intelligence, genetics of mental illness, imagination, lying, puzzles, and twins, this highly-anticipated second edition explores the most intriguing of subjects. (shrink)

This article concerns the interplay between two issues that involve both philosophy and neuroscience: whether the content of phenomenal consciousness is 'rich' or 'sparse', whether phenomenal consciousness goes beyond cognitive access, and how it would be possible for there to be evidence one way or the other.

The phenomenon of `consciousness' is intrinsically related to one's awareness of one's self, of time, and of the physical world. What, then, can be learned about consciousness from people who have suffered brain damage such as amnesia which affects their awareness? This is the question explored by Lawrence Weiskrantz, a distinguished neuropsychologist who has worked with such patients over 30 years. Written in an engaging and accessible style, Consciousness Lost and Found provides a unique perspective on one of the most (...) challenging issues in science today. (shrink)

Blindsight is the term commonly used to describe visually guided behaviour elicited by a stimulus falling within the scotoma (blind area) caused by a lesion of the striate cortex. Such is normally held to be unconscious and to be mediated by subcortical pathways involving the superior colliculus. Blindsight is of considerable theoretical importance since it suggests that destriate man is more like destriate monkey than had been previously believed and also because it supports the classical notion of two visual systems. (...) It is also of potential clinical importance, since it has been claimed recently that systematic practice in blindsight can lead to the recovery of normal visual function in patients with cortical lesions. From a review of the literature it is concluded that all of the phenomena of blindsight can be attributed either to light scatter into unimpaired parts of the visual field or to residual vision resulting from spared striate cortex. The possible contribution f other factors is also considered. It is concluded that blindsight studies have generally failed to control for such nonblindsight interpretations partly because of poor methodology and partly because of difficulties in defining the term. (shrink)

When the stored representation of the meaning of a stimulus is accessed through the processing of a sensory input it is maintained in an activated state for a certain amount of time that allows for further processing. This semantic activation is generally accompanied by conscious identification, which can be demonstrated by the ability of a person to perform discriminations on the basis of the meaning of the stimulus. The idea that a sensory input can give rise to semantic activation without (...) concomitant conscious identification was the central thesis of the controversial research in subliminal perception. Recently, new claims for the existence of such phenomena have arisen from studies in dichotic listening, parafoveal vision, and visual pattern masking. Because of the fundamental role played by these types of experiments in cognitive psychology, the new assertions have raised widespread interest. (shrink)

This article reports four subliminal perception experiments using the relationship between confidence and accuracy to assess awareness. Subjects discriminated among stimuli and indicated their confidence in each discrimination response. Subjects were classified as being aware of the stimuli if their confidence judgments predicted accuracy and as being unaware if they did not. In the first experiment, confidence predicted accuracy even at stimulus durations so brief that subjects claimed to be performing at chance. This finding indicates that subjects's claims that they (...) are ''just guessing'' should not be accepted as sufficient evidence that they are completely unaware of the stimuli. Experiments 2-4 tested directly for subliminal perception by comparing the minimum exposure duration needed for better than chance discrimination performance against the minimum needed for confidence to predict accuracy. The latter durations were slightly but significantly longer, suggesting that under certain circumstances people can make perceptual discriminations even though the information that was used to make those discriminations is not consciously available. (shrink)

As an alternative to establishing awareness thresholds, stimulus contexts in which there were either greater conscious or greater unconscious influences were defined on the basis of performance on an exclusion task. Target words were presented for brief durations and each target word was followed immediately by its three-letter stem. Subjects were instructed to complete each stem with any word other than the target word. With this task, failures to exclude target words indicate greater unconscious influences, whereas successful exclusion indicates greater (...) conscious influences. Conscious influences were dominant at long durations , but unconscious influences were dominant at short durations . Performance on the exclusion task successfully predicated both qualitative differences in Stroop priming and qualitative differences in recognition memory previously associated with the different effects of conscious and unconscious influences. Taken together, these results demonstrate that an exclusion task allows both unconscious and conscious influences to be defined in terms of significant deviations from baseline performance. As such, exclusion tasks provide a method for distinguishing conscious from unconscious influences that does not require establishing thresholds for null awareness. (shrink)

Do studies of perception without awareness and studies of perception without attention address a similar underlying concept of awareness? To answer this question, we compared qualitative differences in performance across variations in stimulus quality with qualitative differences in performance across variations in the direction of attention . The qualitative differences were based on three different phenomena: Stroop priming, false recognition, and exclusion failure. In all cases, variations in stimulus quality and variations in the direction of attention led to parallel findings. (...) These results suggest that perception with and without awareness and perception with and without attention are equivalent ways of describing the same underlying process distinction. (shrink)

How can we disentangle the neural basis of phenomenal consciousness from the neural machinery of the cognitive access that underlies reports of phenomenal consciousness? We can see the problem in stark form if we ask how we could tell whether representations inside a Fodorian module are phenomenally conscious. The methodology would seem straightforward: find the neural natural kinds that are the basis of phenomenal consciousness in clear cases when subjects are completely confident and we have no reason to doubt their (...) authority, and look to see whether those neural natural kinds exist within Fodorian modules. But a puzzle arises: do we include the machinery underlying reportability within the neural natural kinds of the clear cases? If the answer is ‘Yes’, then there can be no phenomenally conscious representations in Fodorian modules. But how can we know if the answer is ‘Yes’? The suggested methodology requires an answer to the question it was supposed to answer! The paper argues for an abstract solution to the problem and exhibits a source of empirical data that is relevant, data that show that in a certain sense phenomenal consciousness overflows cognitive accessibility. The paper argues that we can find a neural realizer of this overflow if assume that the neural basis of phenomenal consciousness does not include the neural basis of cognitive accessibility and that this assumption is justified by the explanations it allows. (shrink)

The disjunctive theory of perception claims that we should understand statements about how things appear to a perceiver to be equivalent to statements of a disjunction that either one is perceiving such and such or one is suffering an illusion (or hallucination); and that such statements are not to be viewed as introducing a report of a distinctive mental event or state common to these various disjoint situations. When Michael Hinton first introduced the idea, he suggested that the burden of (...) proof or disproof lay with his opponent, that what was needed was to show that our talk of how things look or appear to one.. (shrink)

Consciousness is a mongrel concept: there are a number of very different "consciousnesses." Phenomenal consciousness is experience; the phenomenally conscious aspect of a state is what it is like to be in that state. The mark of access-consciousness, by contrast, is availability for use in reasoning and rationally guiding speech and action. These concepts are often partly or totally conflated, with bad results. This target article uses as an example a form of reasoning about a function of "consciousness" based on (...) the phenomenon of blindsight. Some information about stimuli in the blind field is represented in the brains of blindsight patients, as shown by their correct "guesses," but they cannot harness this information in the service of action, and this is said to show that a function of phenomenal consciousness is somehow to enable information represented in the brain to guide action. But stimuli in the blind field are BOTH access-unconscious and phenomenally unconscious. The fallacy is: an obvious function of the machinery of access-consciousness is illicitly transferred to phenomenal consciousness. (shrink)

No mental phenomenon is more central than consciousness to an adequate understanding of the mind. Nor does any mental phenomenon seem more stubbornly to resist theoretical treatment. Consciousness is so basic to the way we think about the mind that it can be tempting to suppose that no mental states exist that are not conscious states. Indeed, it may even seem mysterious what sort of thing a mental state might be if it is not a conscious state. On this way (...) of looking at things, if any mental states do lack consciousness, they are exceptional cases that call for special explanation or qualification. Perhaps dispositional or cognitive states exist that are not conscious, but nonetheless count as mental states. (shrink)

Most contemporary theorists regard the traditional thesis that perception is essentially conscious as just another armchair edict to be abandoned in the wake of empirical discovery. Here I reconsider this dramatic departure from tradition. My aim is not to recapture our prelapsarian confidence that perception is inevitably conscious (though much I say might be recruited to that cause). Instead, I want to problematize the now ubiquitous belief in unconscious perception. The paper divides into two parts. Part One is more purely (...) philosophical. It explains how standard arguments for unconscious perception rely on contentious background assumptions concerning the relation between ordinary perception and the explanatory constructs of scientific psychology. Part Two, in contrast, offers detailed engagement with relevant empirical work. It exposes how, even setting aside the concerns identified in Part One, a dilemma confronts the believer in unconscious perception. This dilemma arises because ordinary perception is an individual-level state or occurrence, yet criteria sufficiently stringent to guarantee that a putatively perceptual state is unconscious vitiate the grounds for its attribution to the individual. The dilemma foments a hypothesis, namely that the conditions for genuine, individual-level perception are sufficient conditions for perceptual consciousness. The viability of this hypothesis should unnerve anyone who thinks unconscious perception is simply an empirical given. (shrink)

Often when there is no attention to an object, there is no conscious perception of it either, leading some to conclude that conscious perception is an attentional phenomenon. There is a well-known perceptual phenomenon—visuo-spatial crowding, in which objects are too closely packed for attention to single out one of them. This article argues that there is a variant of crowding—what I call ‘‘identity-crowding’’—in which one can consciously see a thing despite failure of attention to it. This conclusion, together with new (...) evidence that attention to an object occurs in unconscious perception, suggests there may be a double dissociation between conscious perception of an object and attention to that object, constraining the extent to which consciousness can be constitutively attentional. The argument appeals to a comparison between the minimal resolution (or ‘‘grain’’) of object-attention and object-seeing. (shrink)

Consciousness and Mind presents David Rosenthal's influential work on the nature of consciousness. Central to that work is Rosenthal's higher-order-thought theory of consciousness, according to which a sensation, thought, or other mental state is conscious if one has a higher-order thought that one is in that state. The first four essays develop various aspects of that theory. The next three essays present Rosenthal's homomorphism theory of mental qualities and qualitative consciousness, and show how that theory fits with and helps sustain (...) the HOT theory. A crucial feature of homomorphism theory is that it individuates and taxonomizes mental qualities independently of the way we're conscious of them, and indeed independently of our being conscious of them at all. So the theory accommodates the qualitative character not only of conscious sensations and perceptions, but also of those which fall outside our stream of consciousness. Rosenthal argues that, because this account of mental qualities makes no appeal to consciousness, it enables us to dispel such traditional quandaries as the alleged conceivability of undetectable quality inversion, and to disarm various apparent obstacles to explaining qualitative consciousness and understanding its nature. Six further essays build on the HOT theory to explain various important features of consciousness, among them the complex connections that hold in humans between consciousness and speech, the self-interpretative aspect of consciousness, and the compelling sense we have that consciousness is unified. Two of the essays, one an extended treatment of homomorphism theory, appear here for the first time. There is also a substantive introduction, which draws out the connections between the essays and highlights their implications. (shrink)

Blindsight is a kind of residual vision found in people with lesions to V1. Subjects with blindsight typically report no visual awareness, but they are nonetheless able to make above-chance guesses about the shape, location, color and movement of visual stimuli presented to them in their blind field. A different kind of blindsight, sometimes called type 2 blindsight, is a kind of residual vision found in patients with V1 lesions in the presence of some residual awareness. Type 2 blindsight differs (...) from ordinary visual experience in lacking the particularity, transparency and fine-grainedness often taken to be essential to visual experience, at least in veridical cases. I argue that the case of type 2 blindsight provides a counterexample to the view that these characteristics are essential to veridical visual experience and that this gives us reason to resist the view that visual experience is essentially a perceptual relation to external objects. In the second part of the paper I argue that the case of type 2 blindsight yields important insights into the effects of attentional modulation on perceptual content and that cases of attentional modulation of appearance are not at odds with the view that the phenomenology of visual experience flows from its content. (shrink)

The aim of this paper is to raise some serious worries about anti-representationalism: the recently popular view according to which there are no perceptual representations. Although anti-representationalism is more and more popular, I will argue that we have strong empirical reasons for mistrusting it. More specifically, I will argue that it is inconsistent with some important empirical findings about dorsal perception and about the multimodality of perception.

For the past three decades there has been a substantial amount of scientific evidence supporting the view that attention is necessary and sufficient for perceptual representations to become conscious (i.e., for there to be something that it is like to experience a representational perceptual state). This view, however, has been recently questioned on the basis of some alleged counterevidence. In this paper we survey some of the most important recent findings. In doing so, we have two primary goals. The first (...) is descriptive: we provide a literature review for those seeking an understanding of the present debate. The second is editorial: we suggest that the evidence alleging dissociations between consciousness and attention is not decisive. Thus, this is an opinionated overview of the debate. By presenting our assessment, we hope to bring out both sides in the debate and to underscore that the issues here remain matters of intense controversy and ongoing investigation. (shrink)

The higher order approach to consciousness attempts to build a theory of consciousness from the insight that a conscious state is one that the subject is conscious of. There is a well-known objection1 to the higher order approach, a version of which is fatal. Proponents of the higher order approach have realized that the objection is significant. They have dealt with it via what David Rosenthal calls a “retreat” (2005b, p. 179) but that retreat fails to solve the problem.

It’s often held that undetectable inversion of mental qualities is, if not possible, at least conceivable. It’s thought to be conceivable that the mental quality your visual states exhibit when you see something red in standard conditions is literally of the same type as the mental quality my visual states exhibit when I see something green in such circumstances. It’s thought, moreover, to be conceivable that such inversion of mental qualities could be wholly undetectable by any third-person means. And since (...) first- person access is limited to a single individual, and so could not reveal a disparity in mental quality between us, third-person undetectability means undetectability tout court. (shrink)

Can we consciously see more items at once than can be held in visual working memory? This question has elud- ed resolution because the ultimate evidence is subjects’ reports in which phenomenal consciousness is filtered through working memory. However, a new technique makes use of the fact that unattended ‘ensemble prop- erties’ can be detected ‘for free’ without decreasing working memory capacity.

How should we measure metacognitive sensitivity, i.e. the efficacy with which observers’ confidence ratings discriminate between their own correct and incorrect stimulus classifications? We argue that currently available methods are inadequate because they are influenced by factors such as response bias and type 1 sensitivity . Extending the signal detection theory approach of Galvin, Podd, Drga, and Whitmore , we propose a method of measuring type 2 sensitivity that is free from these confounds. We call our measure meta-d′, which reflects (...) how much information, in signal-to-noise units, is available for metacognition. Applying this novel method in a 2-interval forced choice visual task, we found that subjects’ metacognitive sensitivity was close to, but significantly below, optimality. We discuss the theoretical implications of these findings, as well as related computational issues of the method. We also provide free Matlab code for implementing the analysis. (shrink)

The first edition of Blindsight, written by Lawrence Weiskrantz was an important and highly cited account of studies of the phenomenon - Blindsight. The updated edition retains the original text of the first edition, but brings the book up to date with developments in this area in the past decade.

A recent report by Persaud et al. [Persaud, N., McLeod, P. & Cowey, A. . Post-decision wagering objectively measures awareness. Nature Neuroscience 10, 257–261] addresses a fundamental issue in consciousness science: the experimental measurement of conscious content. The authors propose a novel technique, ‘post-decision wagering’, in which subjects place bets on the correctness of decisions or discriminations. In this note, I critique the authors’ claim that their method “measures awareness directly”.

Subliminal perception (SP) is today considered a well-supported theory stating that perception can occur without conscious awareness and have a significant impact on later behaviour and thought. In this article, we first present and discuss different approaches to the study of SP. In doing this, we claim that most approaches are based on a dichotomic measure of awareness. Drawing upon recent advances and discussions in the study of introspection and phenomenological psychology, we argue for both the possibility and necessity of (...) using an elaborated measure of subjective states. In the second part of the article, we present findings where these considerations are implemented in an empirical study. The results and implications are discussed in detail, both with reference to SP, and in relation to the more general problem of using elaborate introspective reports as data in relation to studies of cognition. (shrink)

Blindsight is the ability of patients with an impaired visual cortex to perform visually in their blind field without acknowledging that performance. This ability has been interpreted as a sign of the absence of phenomenal consciousness, and neuroscientific studies have extensively studied cases of it. Different proposals separate visual form recognition from motion perception, and attempt to show that either the former or the latter is solely responsible for blindsight performance. However, a review of current experimental evidence shows that a (...) poor performance (on both form and motion) is accompanied by poor awareness. Blindsight cases do not influence the qualia debate, because they denote a severe visual performance deficit, and not because of a purportedly non-phenomenal nature of consciousness. (shrink)