I propose a new argument showing that conscious vision sometimes depends constitutively on conscious attention. I criticise traditional arguments for this constitutive connection, on the basis that they fail adequately to dissociate evidence about visual consciousness from evidence about attention. On the same basis, I criticise Ned Block's recent counterargument that conscious vision is independent of one sort of attention (‘cognitive access'). Block appears to achieve the dissociation only because he underestimates the indeterminacy of visual consciousness. I then appeal to (...) empirical work on the interaction between visual indeterminacy and attention, to argue for the constitutive connection. (shrink)

What is the best way of assessing the extent to which people are aware of a stimulus? Here, using a masked visual identification task, we compared three measures of subjective awareness: The Perceptual Awareness Scale , through which participants are asked to rate the clarity of their visual experience; confidence ratings , through which participants express their confidence in their identification decisions, and Post-decision wagering , in which participants place a monetary wager on their decisions. We conducted detailed explorations of (...) the relationships between awareness and identification performance, looking to determine which scale best correlates with performance, and whether we can detect performance in the absence of awareness and how the scales differ from each other in terms of revealing such unconscious processing. Based on these findings we discuss whether perceptual awareness should be considered graded or dichotomous. Results showed that PAS showed a much stronger performance-awareness correlation than either CR or PDW, particularly for low stimulus intensities. In general, all scales indicated above-chance performance when participants claimed not to have seen anything. However, such above-chance performance only showed when we also observed a correlation between awareness and performance. Thus PAS seems to be the most exhaustive measure of awareness, and we find support for above-chance performance in the absence of subjective awareness, but such unconscious knowledge only contributes to performance when we observe conscious knowledge as well. Similarities and differences between scales are discussed in the light of consciousness theories and response strategies. (shrink)

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)

It is an orthodoxy in cognitive science that perception can occur unconsciously. Recently, Hakwan Lau, Megan Peters and Ian Phillips have argued that this orthodoxy may be mistaken. They argue that many purported cases of unconscious perception fail to rule out low degrees of conscious awareness while others fail to establish genuine perception. This paper presents a case of unconscious perception that avoids these problems. It also advances a general principle of ‘phenomenal coherence’ that can insulate some forms of evidence (...) for unconscious perception from the methodological critiques of Lau, Peters and Phillips. (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)

Block () highlights two experimental studies of neglect patients which, he contends, provide ‘dramatic evidence’ for unconscious seeing. In Block's hands this is the highly non-trivial thesis that seeing of the same fundamental kind as ordinary conscious seeing can occur outside of phenomenal consciousness. Block's case for it provides an excellent opportunity to consider a large body of research on clinical syndromes widely held to evidence unconscious perception. I begin by considering in detail the two studies of neglect to which (...) Block appeals. I show why their interpretation as evidence of unconscious seeing faces a series of local difficulties. I then explain how, even bracketing these issues, a long-standing but overlooked problem concerning our criterion for consciousness problematizes the appeal to both studies. I explain why this problem is especially pressing for Block given his view that phenomenal consciousness overflows access consciousness. I further show that it is epidemic—not only affecting all report-based studies of unconscious seeing in neglect, but also analogous studies of the condition most often alleged to show unconscious seeing, namely blindsight. (shrink)

As for most measurement procedures in the course of their development, measures of consciousness face the problem of coordination, i.e., the problem of knowing whether a measurement procedure actually measures what it is intended to measure. I focus on the case of the Perceptual Awareness Scale to illustrate how ignoring this problem leads to ambiguous interpretations of subjective reports in consciousness science. In turn, I show that empirical results based on this measurement procedure might be systematically misinterpreted.

Phillips argues that blindsight is due to response criterion artefacts under degraded conscious vision. His view provides alternative explanations for some studies, but may not work well when one considers several key findings in conjunction. Empirically, not all criterion effects are decidedly non-perceptual. Awareness is not completely abolished for some stimuli, in some patients. But in other cases, it was clearly impaired relative to the corresponding visual sensitivity. This relative dissociation is what makes blindsight so important and interesting.

Consciousness scientists have not reached consensus on two of the most central questions in their field: first, on whether consciousness overflows reportability; second, on the physical basis of consciousness. I review the scientific literature of the 19th century to provide evidence that disagreement on these questions has been a feature of the scientific study of consciousness for a long time. Based on this historical review, I hypothesize that a unifying explanation of disagreement on these questions, up to this day, is (...) that scientific theories of consciousness are underdetermined by the evidence, namely, that they can be preserved “come what may” in front of (seemingly) disconfirming evidence. Consciousness scientists may have to find a way of solving the persistent underdetermination of theories of consciousness to make further progress. (shrink)

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)

Introspective and phenomenological methods are once again being used to support the use of subjective reports, rather than objective behavioural measures, to investigate and measure consciousness. Objective measures are often seen as useful ways of investigating the range of capacities subjects have in responding to phenomena, but are fraught with the interpretive problems of how to link behavioural capacities with consciousness. Instead, gathering subjective reports is seen as a more direct way of assessing the contents of consciousness. This article explores (...) three different ways of gathering subjective reports that have been discussed in recent literature on consciousness, including immediate retrospection (Schwitzgebel [2007]) and two types of introspective training (Overgaard et al. [2004]; Schwitzgebel [2008]). Although not an exhaustive survey of the range of introspective methods now used, the discussion below highlights a range of general methodological problems with introspective methods, many identified up to a century ago. It is argued that none of the methodological problems established in earlier criticisms of the use of subjective reports have been dealt with, yet are still valid criticisms. Given that this is not the first time proponents of introspective, subjective measures of conscious have failed to answer these criticisms, this raises the question of whether the goal of providing a measure of consciousness is a methodological muddle worth pursuing. (shrink)

This paper argues for a position of ‘dark pessimism’ towards introspective reports playing a strong justificatory role in consciousness science, based on the application of frameworks and concepts of measurement. I first show that treating introspective reports as measurements fits well within current discussions of the reliability of introspection, and argue that introspective reports must satisfy at least a minimal definition of measurement in order to play a justificatory role in consciousness science. I then show how treating introspective reports as (...) measurements makes it possible to identify the foundational methodological problems that underlie much of the current philosophical and scientific debate about the status of introspective evidence in studying consciousness. I argue that these problems prevent introspective reports from playing a strong justificatory role and resolving long-standing debates in consciousness science, both in contemporary work and in the future. (shrink)

This paper argues for a position of ‘dark pessimism’ towards introspective reports playing a strong justificatory role in consciousness science, based on the application of frameworks and concepts of measurement. I first show that treating introspective reports as measurements fits well within current discussions of the reliability of introspection, and argue that introspective reports must satisfy at least a minimal definition of measurement in order to play a justificatory role in consciousness science. I then show how treating introspective reports as (...) measurements makes it possible to identify the foundational methodological problems that underlie much of the current philosophical and scientific debate about the status of introspective evidence in studying consciousness. I argue that these problems prevent introspective reports from playing a strong justificatory role and resolving long-standing debates in consciousness science, both in contemporary work and in the future. (shrink)

Sandberg et al. show that the Perceptual Awareness Scale scale is sensitive compared to confidence ratings and wagering in detecting accurate perception. They go on to argue that the PAS scale is hence a sensitive measure of conscious perception compared to confidence ratings, a claim disputed here. The fact that some visual content is conscious does not entail that the visual content relevant to making a discrimination is conscious. For example, if one saw a square but was only aware of (...) seeing a flash of something, then one has not consciously seen a square. When PAS and confidence ratings come in conflict, we suggest that it is confidence ratings that more reliably indicate the conscious status of contents allowing discrimination. (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)

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.

Critics have often misunderstood the higher-order theory (HOT) of consciousness. Here we clarify its position on several issues, and distinguish it from other views such as the global The higher-order theory (HOT) of consciousness has often been misunderstood by critics. Here we clarify its position on several issues, and distinguish it from other views such as the global workspace theory (GWT) and early sensory models (e.g. first-order local recurrency theories). For example, HOT has been criticized for over-intellectualizing consciousness. We show (...) that while higher-order states are cognitively assembled, the requirements are actually considerably less than often presumed. In this sense HOT may be viewed as an intermediate position between GWT and early sensory views. Also, we clarify that most proponents of HOT do not stipulate consciousness as equivalent to metacognition or confidence. Further, compared to other existing theories, HOT can arguably account better for complex everyday experiences, such as of emotions and episodic memories. This makes HOT particularly useful as a framework for conceptualizing pathological mental states. (shrink)

Relationalism holds that perceptual experiences are relations between subjects and perceived objects. But much evidence suggests that perceptual states can be unconscious. We argue here that unconscious perception raises difficulties for relationalism. Relationalists would seem to have three options. First, they may deny that there is unconscious perception or question whether we have sufficient evidence to posit it. Second, they may allow for unconscious perception but deny that the relationalist analysis applies to it. Third, they may offer a relationalist explanation (...) of unconscious perception. We argue that each of these strategies is questionable. (shrink)

Visual control of our actions can be unconscious as well as conscious. The book explores unconscious and conscious vision, investigated using psychophysical and brain-recording methods. The book sheds new light on and advances experimental, philosophical, and scholarly research on visual consciousness.

The source of endless speculation and public curiosity, our scientific quest for the origins of human consciousness has expanded along with the technical capabilities of science itself and remains one of the key topics able to fire public as much as academic interest. Yet many problematic issues, identified in this important new book, remain unresolved. Focusing on a series of methodological difficulties swirling around consciousness research, the contributors to this volume suggest that ‘consciousness’ is, in fact, not a wholly viable (...) scientific concept. Supporting this ‘eliminativist‘ stance are assessments of the current theories and methods of consciousness science in their own terms, as well as applications of good scientific practice criteria from the philosophy of science. For example, the work identifies the central problem of the misuse of qualitative difference and dissociation paradigms, often deployed to identify measures of consciousness. It also examines the difficulties that attend the wide range of experimental protocols used to operationalise consciousness—and the implications this has on the findings of integrative approaches across behavioural and neurophysiological research. The work also explores the significant mismatch between the common intuitions about the content of consciousness, that motivate much of the current science, and the actual properties of the neural processes underlying sensory and cognitive phenomena. Even as it makes the negative eliminativist case, the strong empirical grounding in this volume also allows positive characterisations to be made about the products of the current science of consciousness, facilitating a re-identification of target phenomena and valid research questions for the mind sciences.​. (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.

Consciousness is currently a thriving area of research in psychology and neuroscience. While this is often attributed to events that took place in the early 1990s, consciousness studies today are a continuation of research that started in the late 19th century and that continued throughout the 20th century. From the beginning, the effort built on studies of animals to reveal basic principles of brain organization and function, and of human patients to gain clues about consciousness itself. Particularly important and our (...) focus here is research in the 1950s, 1960s, and 1970s involving three groups of patients—amnesia, split brain, and blindsight. Across all three groups, a similar pattern of results was found—the patients could respond appropriately to stimuli that they denied seeing (or in the case of amnesiacs, having seen before). These studies paved the way for the current wave of research on consciousness. The field is, in fact, still grappling with the implications of the findings showing that the ability to consciously know and report the identity of a visual stimulus can be dissociated in the brain from the mechanisms that underlie the ability to behave in a meaningful way to the same stimulus. (shrink)

Berger and Mylopoulos (2019) critique recent scepticism about unconscious perception, focusing on experimental work from Peters and Lau, and theoretical work of my own. Central to their wide-ranging discussion is the claim that unconscious perception occupies a default status within both experimental and folk psychology. Here, I argue to the contrary that a conscious-perception-only model should be our default. Along the way, I offer my own analysis of Peters and Lau's study, assess the folk psychological status of unconscious perception, discuss (...) vision-for-action, and confront an important dilemma which Berger and Mylopoulos raise for the sceptic concerning the existence of unconscious mentality in general. (shrink)

While there seems to be much evidence that perceptual states can occur without being conscious, some theorists recently express scepticism about unconscious perception. We explore here two kinds of such scepticism: Megan Peters and Hakwan Lau's experimental work regarding the well-known problem of the criterion -- which seems to show that many purported instances of unconscious perception go unreported but are weakly conscious -- and Ian Phillips' theoretical consideration, which he calls the 'problem of attribution' -- the worry that many (...) purported examples of unconscious perception are not perceptual, but rather merely informational and subpersonal. We argue that these concerns do not undermine the evidence for unconscious perception and that this sceptical approach results in a dilemma for the sceptic, who must either deny that there is unconscious mentality generally or explain why perceptual states are unique in the mind such that they cannot occur unconsciously. Both options, we argue, are problematic. (shrink)