To study consciousness, scientists need to determine when participants are conscious and when they are not. They do so with consciousness detection procedures. A recurring skeptical argument against those procedures is that they cannot be calibrated: there is no way to make sure that detection outcomes are accurate. In this article, I address two main skeptical arguments purporting to show that consciousness scientists cannot calibrate detection procedures. I conclude that there is nothing wrong with calibration in consciousness science.

The Hard Problem is surrounded by a vast literature, to which it is increasingly hard to contribute to in any meaningful way. Accordingly, the strategy here is not to offer any new metaphysical or ‘in principle’ arguments in favour of the success of materialism, but to assume a Type Q(uinian) approach and look to contemporary consciousness science to see how the concept of consciousness fares there, and what kind of explanations we can hope to offer of it. It is suggested (...) that while they will be materialist explanations, they will not be of the form that many scientists and philosophers would have us believe, but instead prompt a very different set of expectations and research projects. (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)

Contemporary studies in unconscious cognition are essentially founded on dissociation, i.e., on how it dissociates with respect to conscious mental processes and representations. This is claimed to be in so many and diverse ways that one is often lost in dissociation. In order to reduce this state of confusion we here carry out two major tasks: based on the central distinction between cognitive processes and representations, we identify and isolate the main dissociation paradigms; we then critically analyze their key tenets (...) and reported findings. (shrink)

Baars contends that we must ask answerable questions about consciousness, and that to do so will require definitions of consciousness that permit "contrastive analysis". I endorse this general approach, but find several of Baars claims of processing without consciousness, unconvincing. I show that a more cautious definition of "non-conscious" than Baars' need not impede experimentation and is more likely to enjoy universal agreement.

A number of ways of taxonomizing human learning have been proposed. We examine the evidence for one such proposal, namely, that there exist independent explicit and implicit learning systems. This combines two further distinctions, between learning that takes place with versus without concurrent awareness, and between learning that involves the encoding of instances versus the induction of abstract rules or hypotheses. Implicit learning is assumed to involve unconscious rule learning. We examine the evidence for implicit learning derived from subliminal learning, (...) conditioning, artificial grammar learning, instrumental learning, and reaction times in sequence learning. We conclude that unconscious learning has not been satisfactorily established in any of these areas. The assumption that learning in some of these tasks is predominantly based on rule abstraction is questionable. When subjects cannot report the “implicitly learned” rules that govern stimulus selection, this is often because their knowledge consists of instances or fragments of the training stimuli rather than rules. In contrast to the distinction between conscious and unconscious learning, the distinction between instance and rule learning is a sound and meaningful way of taxonomizing human learning. We discuss various computational models of these two forms of learning. (shrink)

This is my first publication of the distinction between phenomenal consciousness and access consciousness, though not using quite those terms. It ends with this: "The upshot is this: If Searle is using the access sense of "consciousness," his argument doesn't get to first base. If, as is more likely, he intends the what-it-is-like sense, his argument depends on assumptions about issues that the cognitivist is bound to regard as deeply unsettled empirical questions." Searle replies: "He refers to what he calls (...) an "access sense of consciousness." On my account there is no such sense.". (shrink)

This reply to five continuing commentaries on my 1991 target article on “Is human information processing conscious” focuses on six related issues: 1) whether focal attentive processing replaces consciousness as a causal agent in third-person viewable human information processing, 2)whether consciousness can be dissociated from human information processing, 3) continuing disputes about definitions of "consciousness" and about what constitutes a “conscious process” , 4) how observer-relativity in psychology relates (and does not relate) to relativity in physics, 5) whether the first-person (...) viewable causal efficacy of consciousness counts as ‘real’ causal efficacy and 6) a clarification of the sense in which first- and third-person causal accounts of mental processing are complementary and mutually irreducible. (shrink)

Block's P-/A-consciousness distinction rules out P's involving a specific kind of cognitive access and commits him to a “strong” Pconsciousness. This not only confounds plausible research in the area but betrays an anosognosia about Wittgenstein's diagnosis about our philosophical “introspection” of mysterious inner processes.

Block has attempted to reduce the confusion and controversy concerning the term “consciousness” by suggesting that there are two forms or types of consciousness, each of which has several characteristics or properties. This suggestion appears to further becloud the topic, however. Perhaps consciousness cannot be defined adequately and should not be considered as a topic that can be studied scientifically.

Here, we explore the sensitivity of different awareness scales in revealing conscious reports on visual emotion perception. Participants were exposed to a backward masking task involving fearful faces and asked to rate their conscious awareness in perceiving emotion in facial expression using three different subjective measures: confidence ratings , with the conventional taxonomy of certainty, the perceptual awareness scale , through which participants categorize “raw” visual experience, and post-decision wagering , which involves economic categorization. Our results show that the CR (...) measure was the most exhaustive and the most graded. In contrast, the PAS and PDW measures suggested instead that consciousness of emotional stimuli is dichotomous. Possible explanations of the inconsistency were discussed. Finally, our results also indicate that PDW biases awareness ratings by enhancing first-order accuracy of emotion perception. This effect was possibly a result of higher motivation induced by monetary incentives. (shrink)

In agreement with some of the ideas expressed by Perruchet & Vinter (P&V), we believe that some phenomena hitherto attributed to processing may in fact reflect a fundamental distinction between direct and reflexive forms of consciousness. This dichotomy, developed by the phenomenological tradition, is substantiated by examples coming from experimental psychology and lesion neuropsychology.

The single-word semantic priming paradigm is a tool for investigating how and when word meaning activation occurs during visual word recognition. The prime task effect refers to the elimination of the typically robust semantic priming effect by a nonsemantic prime task . The purpose of this paper is to provide a tutorial review of the literature examining the prime task effect. Understanding the nature of this effect has implications for delineating how selective attention modulates evidence for semantic activation during word (...) reading. These implications are outlined. Additionally, speculations for how these issues of selective attention relate to awareness are offered. (shrink)

Subjects classified visible 2-digit numbers as larger or smaller than 55. Target numbers were preceded by masked 2-digit primes that were either congruent (same relation to 55) or incongruent. Experiments 1 and 2 showed prime congruency effects for stimuli never included in the set of classified visible targets, indicating subliminal priming based on long-term semantic memory. Experiments 2 and 3 went further to demonstrate paradoxical unconscious priming effects resulting from task context. For example, after repeated practice classifying 73 as larger (...) than 55, the novel masked prime 37 paradoxically facilitated the “larger” response. In these experiments task context could induce subjects to unconsciously process only the leftmost masked prime digit, only the rightmost digit, or both independently. Across 3 experiments, subliminal priming was governed by both task context and long-term semantic memory. (shrink)

This is a bibliography of books and articles on consciousness in philosophy, cognitive science, and neuroscience over the last 30 years. There are three main sections, devoted to monographs, edited collections of papers, and articles. The first two of these sections are each divided into three subsections containing books in each of the main areas of research. The third section is divided into 12 subsections, with 10 subject headings for philosophical articles along with two additional subsections for articles in cognitive (...) science and neuroscience. Of course the division is somewhat arbitrary, but I hope that it makes the bibliography easier to use. This bibliography has first been compiled by Thomas Metzinger and David Chalmers to appear in print in two philosophical anthologies on conscious experience . From 1995 onwards it has been continuously updated by Thomas Metzinger, and now is freely available as a PDF-, RTF-, or HTML-file. This bibliography mainly attempts to cover the Anglo-Saxon and German debates, in a non-annotated, fully formatted way that makes it easy to "cut and paste" from the original file. To a certain degree this bibliography also contains items in other languages than English and German - all submissions in other languages are welcome. Last update of current version: July 13th, 2001. (shrink)

The repercussions of unconscious priming on the neural correlates subsequent cognition have been explored previously. However, the neural dynamics during the unconscious processing remains largely uncharted. To assess both the complexity and temporal dynamics of unconscious cognition the present study contrasts the evoked response from classes of masked stimuli with three different levels of complexity; words, consonant strings, and blanks. The evoked response to masked word stimuli differed from both consonant strings and blanks, which did not differ from each other. (...) This response was qualitatively different to any evoked potential observed when stimuli were consciously visible and peaked at 140 ms, earlier than is usually associated with differences between words and strings and 100 ms earlier than word-consonant string differences in the visible condition. The evoked response demonstrates a qualitatively distinct signature of unconscious cognition and directly demonstrates the extraction of abstract information under subliminal conditions. (shrink)

To what extent do we know our own minds when making decisions? Variants of this question have preoccupied researchers in a wide range of domains, from mainstream experimental psychology to cognitive neuroscience and behavioral economics. A pervasive view places a heavy explanatory burden on an intelligent cognitive unconscious, with many theories assigning causally effective roles to unconscious influences. This article presents a novel framework for evaluating these claims and reviews evidence from three major bodies of research in which unconscious factors (...) have been studied: multiple-cue judgment, deliberation without attention, and decisions under uncertainty. Studies of priming and the role of awareness in movement and perception are also given brief consideration. The review highlights that inadequate procedures for assessing awareness, failures to consider artifactual explanations of “landmark” results, and a tendency to uncritically accept conclusions that fit with our intuitions have all contributed to unconscious influences being ascribed inflated and erroneous explanatory power in theories of decision making. The review concludes by recommending that future research should focus on tasks in which participants' attention is diverted away from the experimenter's hypothesis, rather than the highly reflective tasks that are currently often employed. (shrink)

O'Brien & Opie's (O&O's) theory demands a view of unconscious processing that is incompatible with virtually all current PDP models of neural activity. Relative to the alternatives, the theory is closer to an AI than a parallel distributed processing (PDP) perspective, and its treatment of phenomenology is ad hoc. It raises at least one important question: Could features of network relaxation be the “switch” that turns an unconscious into a conscious network?

This paper replies to the first 36 commentaries on my target article on “Is human information processing conscious?” (Behavioral and Brain Sciences,1991, pp.651-669). The target article focused largely on experimental studies of how consciousness relates to human information processing, tracing their relation from input through to output, while discussion of the implications of the findings both for cognitive psychology and philosophy of mind was relatively brief. The commentaries reversed this emphasis, and so, correspondingly, did the reply. The sequence of topics (...) in the reply roughly follows that of the target article. The discussion begins with a reconsideration of the details of the empirical findings, whether they can be extrapolated to non-laboratory settings, and the extent to which one can rely on their use of subjective reports. This is followed by an in-depth discussion of what is meant by “conscious processing” and of how phenomenal consciousness relates to attentional processing. We then turn to broader philosophical and theoretical issues. I point out some of the reasons why I do not support epiphenomenalism, dualist-interactionism, or reductionism, and elaborate on how first- and third-person views of the mind can be regarded as complementary and mutually irreducible. I suggest how the relation of conscious experiences to their neural correlates can be understood in terms of a dual-aspect theory of information,and how this might be used to resolve some of the paradoxes surrounding the causal interactions of consciousness and brain. I also suggest that, viewed from a first-person perspective, consciousness gives purpose to existence, which allows a different way of viewing its role in evolution. (shrink)

What, in essence, characterizes the mind? According to Searle, the potential to be conscious provides the only definitive criterion. Thus, conscious states are unquestionably "mental"; "shallow unconscious" states are also "mental" by virtue of their capacity to be conscious (at least in principle); but there are no "deep unconscious mental states" - i.e. those rules and procedures without access to consciousness, inferred by cognitive science to characterize the operations of the unconscious mind are not mental at all. Indeed, according to (...) Searle, they have no ontological status - they are simply ways of describing some interesting facets of purely physiological phenomena. (shrink)

This essay is a sustained attempt to bring new light to some of the perennial problems in philosophy of mind surrounding phenomenal consciousness and introspection through developing an account of sensory and phenomenal concepts. Building on the information-theoretic framework of Dretske (1981), we present an informational psychosemantics as it applies to what we call sensory concepts, concepts that apply, roughly, to so-called secondary qualities of objects. We show that these concepts have a special informational character and semantic structure that closely (...) tie them to the brain states realizing conscious qualitative experiences. We then develop an account of introspection which exploits this special nature of sensory concepts. The result is a new class of concepts, which, following recent terminology, we call phenomenal concepts: these concepts refer to phenomenal experience itself and are the vehicles used in introspection. On our account, the connection between sensory and phenomenal concepts is very tight: it consists in different semantic uses of the same cognitive structures underlying the sensory concepts, such as the concept of red. Contrary to widespread opinion, we show that information theory contains all the resources to satisfy internalist intuitions about phenomenal consciousness, while not offending externalist ones. A consequence of this account is that it explains and predicts the so-called conceivability arguments against physicalism on the basis of the special nature of sensory and phenomenal concepts. Thus we not only show why physicalism is not threatened by such arguments, but also demonstrate its strength in virtue of its ability to predict and explain away such arguments in a principled way. However, we take the main contribution of this work to be what it provides in addition to a response to those conceivability arguments, namely, a substantive account of the interface between sensory and conceptual systems and the mechanisms of introspection as based on the special nature of the information flow between them. (shrink)

The implicit-explicit distinction is applied to knowledge representations. Knowledge is taken to be an attitude towards a proposition which is true. The proposition itself predicates a property to some entity. A number of ways in which knowledge can be implicit or explicit emerge. If a higher aspect is known explicitly then each lower one must also be known explicitly. This partial hierarchy reduces the number of ways in which knowledge can be explicit. In the most important type of implicit knowledge, (...) representations merely reflect the property of objects or events without predicating them of any particular entity The dearest cases of explicit knowledge of a fact are representations of one's own attitude of knowing that fact. These distinctions are discussed in their relationship to similar distinctions such as procedural-declarative, conscious unconscious, verbalizable-nonverbalizable, direct-indirect tests, and automatic voluntary control. This is followed by an outline of how these distinctions can be used to integrate and relate the often divergent uses of the implicit-explicit distinction in different research areas. We illustrate this for visual perception, memory, cognitive development, and artificial grammar learning. (shrink)