Much of recent philosophy of perception is oriented towards accounting for the phenomenal character of perception—what it is like to perceive—in a non-mentalistic way—that is, without appealing to mental objects or mental qualities. In opposition to such views, I claim that the phenomenal character of perception of a red round object cannot be explained by or reduced to direct awareness of the object, its redness and roundness—or representation of such objects and qualities. Qualities of perception that are not captured by (...) what one is directly aware of or by representational content are instances of what Gilbert Harman has called “mental paint” (Block, 1990; Harman, 1990). The claim of this paper is that empirical facts about attention point in the direction of mental paint. The argument starts with the claim (later modified) that when one moves one's attention around a scene while keeping one's eyes fixed, the phenomenology of perception can change in ways that do not reflect which qualities of objects one is directly aware of or the way the world is represented to be. These changes in the phenomenology of perception cannot be accounted for in terms of awareness of or representation of the focus of attention because they manifest themselves in experience as differences in apparent contrast, apparent color saturation, apparent size, apparent speed, apparent time of occurrence and other appearances. There is a way of coping with these phenomena in terms of vague contents, but vague contents cannot save direct realism or representationism because the kind of vagueness required clashes wth the phenomenology itself. (shrink)

Philosophers have lately seized upon Sperling's partial report technique and subsequent work on iconic memory in support of controversial claims about perceptual experience, in particular that phenomenology overflows cognitive access. Drawing on mounting evidence concerning postdictive perception, I offer an interpretation of Sperling's data in terms of cue-sensitive experience which fails to support any such claims. Arguments for overflow based on change-detection paradigms (e.g. Landman et al., 2003; Sligte et al., 2008) cannot be blocked in this way. However, such paradigms (...) are fundamentally different from Sperling's and, for rather different reasons, equally fail to establish controversial claims about perceptual experience. (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)

Is consciousness all in the head, or might the minimal physical substrate for some forms of conscious experience include the goings on in the (rest of the) body and the world? Such a view might be dubbed (by analogy with Clark and Chalmers’s ( 1998 ) claims concerning ‘the extended mind’) ‘the extended conscious mind’. In this article, I review a variety of arguments for the extended conscious mind, and find them flawed. Arguments for extended cognition, I conclude, do not (...) generalize to arguments for an extended conscious mind. (shrink)

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)

Blindsight and vision for action seem to be exemplars of unconscious visual processes. However, researchers have recently argued that blindsight is not really a kind of uncon- scious vision but is rather severely degraded conscious vision. Morten Overgaard and col- leagues have recently developed new methods for measuring the visibility of visual stimuli. Studies using these methods show that reported clarity of visual stimuli correlates with accuracy in both normal individuals and blindsight patients. Vision for action has also come under (...) scrutiny. Recent findings seem to show that information processed by the dor- sal stream for online action contributes to visual awareness. Some interpret these results as showing that some dorsal stream processes are conscious visual processes (e.g., Gallese, 2007; Jacob & Jeannerod, 2003). The aim of this paper is to provide new support for the more traditional view that blindsight and vision for action are genuinely unconscious per- ceptual processes. I argue that individuals with blindsight do not have access to the kind of purely qualitative color and size information which normal individuals do. So, even though people with blindsight have a kind of cognitive consciousness, visual information process- ing in blindsight patients is not associated with a distinctly visual phenomenology. I argue further that while dorsal stream processing seems to contribute to visual awareness, only information processed by the early dorsal stream (V1, V2, and V3) is broadcast to working memory. Information processed by later parts of the dorsal stream (the parietal lobe) never reaches working memory and hence does not correlate with phenomenal awareness. I con- clude that both blindsight and vision for action are genuinely unconscious visual processes. (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)

It is widely thought that focusing on highly skilled movements while performing them hinders their execution. Once you have developed the ability to tee off in golf, play an arpeggio on the piano, or perform a pirouette in ballet, attention to what your body is doing is thought to lead to inaccuracies, blunders, and sometimes even utter paralysis. Here I re-examine this view and argue that it lacks support when taken as a general thesis. Although bodily awareness may often interfere (...) with well-developed rote skills, like climbing stairs, I suggest that it is typically not detrimental to the skills of expert athletes, performing artists, and other individuals who endeavor to achieve excellence. Along the way, I present a critical analysis of some philosophical theories and behavioral studies on the relationship between attention and bodily movement, an explanation of why attention may be beneficial at the highest level of performance and an error theory that explains why many have thought the contrary. Though tentative, I present my view as a challenge to the widespread starting assumption in research on highly skilled movement that at the pinnacle of skill attention to one's movement is detrimental. (shrink)

In this paper I examine the dispute between Hakwan Lau, Ned Block, and David Rosenthal over the extent to which empirical results can help us decide between first-order and higher-order theories of consciousness. What emerges from this is an overall argument to the best explanation against the first-order view of consciousness and the dispelling of the mythological notion of phenomenological overflow that comes with it.

One central brand of representationalism claims that the specific phenomenal character of an experience is fully determined by its content. A challenge for this view is that cognitive and perceptual experiences sometimes seem to have the same representational content while differing in phenomenal character. In particular, it might seem that one can have faint imagery experiences or conscious thoughts with the same contents as vivid perceptual experiences. This paper argues that such cases never arise, and that they are probably metaphysically (...) impossible. I also suggest a fully representational account of differences in vividness between phenomenal experiences. (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)

We owe the problem of the speckled hen to Gilbert Ryle. It was suggested to A.J. Ayer by Ryle in connection with Ayer’s account of seeing. Suppose that you are standing before a speckled hen with your eyes trained on it. You are in good light and nothing is obstructing your view. You see the hen in a single glance. The hen has 47 speckles on its facing side, let us say, and the hen ap­ pears speckled to you. On (...) Ayer’s view, in seeing the hen, you directly see a speckled sense-datum or appearance. Ryle wondered how many speckles there are on the sense-datum. After all, intu­ itively, the hen does not appear to you to have 47 speckles. And if this is the case, then it does not present to you an appearance with 47 speckles. Equally, however, the hen does not appear to you not to have 47 speckles. So, it does not present an appearance that lacks 47 speckles either. (shrink)

Conscious visual perception can fail in many circumstances. However, little is known about the causes and processes leading to failures of visual awareness. In this study, we introduce a new signal detection measure termed subjective discriminability of invisibility that allows one to distinguish between subjective blindness due to reduction of sensory signals or to lack of attentional access to sensory signals. The SDI is computed based upon subjective confidence in reporting the absence of a target . Using this new measure, (...) we found that target misses were subjectively indistinguishable from physical absence when contrast reduction, backward masking and flash suppression were used, whereas confidence was appropriately modulated when dual task, attentional blink and spatial uncertainty methods were employed. These results show that failure of visual perception can be identified as either a result of perceptual or attentional blindness depending on the circumstances under which visual awareness was impaired. (shrink)

Contrary to Block's assertion, “identity-crowding” does not provide an interesting instance of object-seeing without object-attention. The successful judgments and unusual phenomenology of identity-crowding are better explained by unconscious perception and non-perceptual phenomenology associated with cognitive states. In identity-crowding, as in other cases of crowding, subjects see jumbled textures and cannot individuate the items contributing to those textures in the absence of attention. Block presents an attenuated sense in which identity-crowded items are seen, but this is irrelevant to the debate about (...) phenomenal experience of an object in the absence of object-attention. Finally, even unconscious object perception in identity-crowding likely involves an attention-like selective process. (shrink)

Consciousness is now a hot topic in both philosophy and the cognitive sciences, yet there is much controversy over how to measure it. First, it is not clear whether biased subjective reports should be taken as adequate for measuring consciousness, or if more objective measures are required. Ways to benefit from the advantages of both these measures in the form of ‘Type 2’ metacognitive measures are under development, but face criticism. Research into neurophysiological measures of consciousness is potentially very valuable, (...) but often hindered by its dependence on behavioural measures that are themselves controversial. Newer informational measures are theoretically interesting, but as yet not easily applicable, while other measures of consciousness are designed for application in clinical cases . Although much optimism accompanies research into measures of consciousness, the controversies and methodological problems reviewed here suggest that making progress in this area may be more difficult than is often acknowledged. (shrink)

This article challenges Block's ‘overflow argument’ for the conclusion that phenomenal consciousness and access-consciousness are distinct. It shows that the data can be explained just as well in terms of a distinction between contents that are made globally accessible through bottom–up sensory stimulation and those that are sustained and made available in working memory through top-down attention.

In this paper, we address the different ways in which dream research can contribute to interdisciplinary consciousness research. As a second global state of consciousness aside from wakefulness, dreaming is an important contrast condition for theories of waking consciousness. However, programmatic suggestions for integrating dreaming into broader theories of consciousness, for instance by regarding dreams as a model system of standard or pathological wake states, have not yielded straightforward results. We review existing proposals for using dreaming as a model system, (...) taking into account concerns about the concept of modeling and the adequacy and practical feasibility of dreaming as a model system. We conclude that existing modeling approaches are premature and rely on controversial background assumptions. Instead, we suggest that contrastive analysis of dreaming and wakefulness presents a more promising strategy for integrating dreaming into a broader research context and solving many of the problems involved in the modeling approach. (shrink)

This paper concerns the role of the structural properties of representations in determining the nature of their content. I take as a starting point Fodor's (2007) and Heck's (2007) recent arguments making the iconic structure of perceptual representations essential in establishing their content as content of a different (nonconceptual) kind. I argue that the prima facie state–content error this strategy seems to display is nothing but a case of “state–content error error,” i.e., the mistake of considering that the properties that (...) characterize the type of content certain representations have are indeed independent of their structural properties. I also consider another objection to the general strategy, namely that it falls short of showing that the nonconceptual content of perceptual experiences thus established is the kind of content that figures in true explanations of intentional behavior. I concede this point in respect of Fodor's version of the strategy, while denying that it has any bearing on Heck's approach. The success of this objection in Heck's case ultimately depends, I argue, upon an unjustified commitment to a certain empirically suspect model of perception. (shrink)

This introduction presents a state of the art of philosophical research on cognitive phenomenology and its relation to the nature of conscious thinking more generally. We firstly introduce the question of cognitive phenomenology, the motivation for the debate, and situate the discussion within the fields of philosophy, cognitive psychology and consciousness studies. Secondly, we review the main research on the question, which we argue has so far situated the cognitive phenomenology debate around the following topics and arguments: phenomenal contrast, epistemic (...) arguments and challenges, introspection, ontology and temporal character, intentionality, inner speech, agency, holistic perspective, categorical perception, value, and phenomenological description. Thirdly, we suggest future developments by pointing to four questions that can be explored in relation to the cognitive phenomenology discussion: the self and self-awareness, attention, emotions and general the... (shrink)

Two popular theses central to recent theorizing about consciousness are the transitivity principle and the transparency of experience. According to the former, conscious mental states are mental states we are aware of in some way. According to the latter, there is some awareness-relation that we seemingly cannot bear to our experiences. I argue that, within certain reasonable constraints, there is no precisification of these theses that renders them compatible.

Both the global workspace theory and Block’s distinction between phenomenal and access consciousness, are central in the current debates about consciousness and the neural correlates of consciousness. In this article, a unifying global workspace model for phenomenal and access consciousness is proposed. In the model, recurrent neural interactions take place in distinct yet interacting access and phenomenal brain loops. The effectiveness of feedback signaling onto sensory cortical maps is emphasized for the neural correlates of phenomenal consciousness. Two forms of top-down (...) attention, attention for perception and attention for access, play differential roles for phenomenal and access consciousness. The model is implemented in a neural network form, with the simulation of single and multiple visual object processing, and of the attentional blink. (shrink)

Blindsight, the ability to blindly discriminate wavelength and other aspects of stimuli in a blind field, sometimes occurs in people with lesions to striate (V1) cortex. There is currently no consensus on whether qualitative color information of the sort that is normally computed by double opponent cells in striate cortex is indeed computed in blindsight but doesn’t reach awareness, perhaps owing to abnormal neuron responsiveness in striate or extra-striate cortical areas, or is not computed at all. The existence of primesight, (...) the experience of colored afterimages in blindsight, has been taken to suggest that qualitative color information is computed either in pre-striate or striate cortical areas but is not broadcast to working memory. I argue here that a recent study in which color phosphenes were induced in a blindsighter using bilateral transcranial magnetic stimulation indicates that computations necessary for conscious color vision are lost in blindsight. Owing to this loss, the neural responsiveness in extrastriate cortical areas is abnormal and hence is unable to give rise to color awareness. Blindsight is thus degraded vision in which the computations necessary for conscious color vision have been lost. (shrink)

Self-awareness is viewed here as the phenotypic expression of an interaction between genes and the environment. Brain and behavioral development of fetuses and newborn infants are a rich source of information regarding what might constitute minimal self-awareness. Research indicates that newborns have feeling experience. Unlike automata, they do not just sense and respond to proximal stimulations. In light of the explosive brain growth that takes place inside and outside of the womb, first signs of feeling as opposed to sensing experience (...) are discussed. Feeling experience is considered as the necessary condition for having minimal self-awareness. Both would co-emerge in development. However, minimal self-awareness is rapidly supplemented with an awareness that is not just perceptual, but also conceptual and ethical, primarily defined in relation to and by others. (shrink)

The well-known distinction between access consciousness and phenomenal consciousness has moved away from the conceptual domain into the empirical one, and the debate now is focused on whether the neural mechanisms of cognitive access are constitutive of the neural correlate of phenomenal consciousness. In this paper, I want to analyze the consequences that a negative reply to this question has for the cognitive phenomenology thesis – roughly the claim that there is a “proprietary” phenomenology of thoughts. If the mechanisms responsible (...) for cognitive access can be disentangled from the mechanisms that give rise to phenomenology in the case of perception and emotion, then the same disentanglement is to be expected in the case of thoughts. This, in turn, presents, as I argue, a challenge to the cognitive phenomenology thesis: either there are thoughts with cognitive phenomenology we lack cognitive access to or there are good reasons to doubt that there is such a thing as cognitive phenomenology. I discuss a... (shrink)

In a recent commentary, Memmert critiqued claims that attentional misdirection is directly analogous to inattentional blindness and cautioned against assuming too close a similarity between the two phenomena. One important difference highlighted in his analysis is that most lab-based inductions of IB rely on the taxing of attention through a demanding primary task, whereas attentional misdirection typically involves simply the orchestration of spatial attention. The present commentary argues that, rather than reflecting a complete dissociation between IB and attentional misdirection, this (...) difference highlights potential grounds for delineating mechanistically distinct forms of IB: spatial inattentional blindness, which stems from the covert misallocation of spatial attention, and central inattentional blindness, which stems from disruption or preoccupation of perceptual mechanisms that interface with higher-level processes such as working memory. Recognition of such distinctions can help situate theoretical understanding of IB more firmly within the context of the broader attention literature. (shrink)

Most materialist responses to the zombie argument against materialism take either a “type-A” or “type-B” approach: they either deny the conceivability of zombies or accept their conceivability while denying their possibility. However, a “type-Q” materialist approach, inspired by Quinean suspicions about a priority and modal entailment, rejects the sharp line between empirical and conceptual truths needed for the traditional responses. In this paper, I develop a type-Q response to the zombie argument, one stressing the theory-laden nature of our conceivability and (...) possibility intuitions. I argue that our first-person access to the conscious mind systematically misleads us into thinking that the distinctive qualities of conscious experience—qualia—are nonfunctional. Qualia, I contend, are functional, even though they do not seem to be. To support my claim, I introduce the “meditations” of Rene Descartes’ zombie twin. This establishes the plausibility of an appearance/reality distinction for consciousness and it undermines various anti-materialist objections based on privileged first-person access. I conclude that the best overall theory posits an appearance/reality distinction for qualia, and this, for the type-Q materialist, is decisive. (shrink)

Can one be fooled into believing that one intended an action that one in fact did not intend? Past experimental paradigms have demonstrated that participants, when provided with false perceptual feedback about their actions, can be fooled into misperceiving the nature of their intended motor act. However, because veridical proprioceptive/perceptual feedback limits the extent to which participants can be fooled, few studies have been able to answer our question and induce the illusion to intend. In a novel paradigm addressing this (...) question, participants were instructed to move a line on the computer screen by use of a phony brain–computer interface. Line movements were actually controlled by computer program. Demonstrating the illusion to intend, participants reported more intentions to move the line when it moved frequently than when it moved infrequently. Consistent with ideomotor theory, the finding illuminates the intimate liaisons among ideomotor processing, the sense of agency, and action production. (shrink)

How is it that, as fiction readers, we are nonplussed by J. K. Rowling's prescription to imagine Ronan, Bane, and Magorian, three different centaurs of the Forbidden Forrest at Hogwarts? It is usually held in the philosophical literature on fictional discourse that singular imaginings of fictional objects are impossible, given the blatant nonexistence of such objects. In this paper, I have a dual purpose: on the one hand, to show that, without being committed to Meinongeanism, we can explain the phenomenon (...) of singular imaginings of different nonexistents of the same kind; while, at the same time, to attribute this position to Thomas Reid, thus correcting some misunderstandings of his view on imagination. (shrink)

Normal perception involves conscious experience of the world. What I call the Content View, (CV), attempts to account for this in terms of the representational content of perception (Brewer, 2011, esp. ch. 4). I offer a new argument here against this view. Ascription of personal level content, either conceptual or nonconceptual, depends on the idea that determinate predicational information is conveyed to the subject. This determinate predication depends upon the exercise of certain personal level capacities for categorization and discrimination. Exercise (...) of such personal level capacities depends in turn upon conscious selective attention. Yet conscious visual acquaintance with the world is the prior ground for the possibility of any such conscious selective attention. Acquaintance obtains throughout the visual field: where conscious attention is not actually directed as well as where it is. So acquaintance does not depend upon conscious selective attention. Thus, acquaintance is not sufficient for the exercise of the relevant personal level capacities. Exercise of these capacities is nevertheless necessary for personal level content. Therefore visual acquaintance cannot be understood in terms of perceptual content: basic conscious experience of the world is not a matter of anything like the predication involved in perceptual content. It is rather the relational ground for the possibility of such predication. (shrink)

One of the possible ways to explain the experience of visual richness is to posit a level of nonconceptual or phenomenal experience. The contents of this level of experience have recently been equated with the contents of sensory memory. It will be argued that sensory memory cannot provide these contents along two broad points. First, the conception of sensory memory relied on by these authors conflates the phenomena of visible and informational persistence, and makes use of an outdated “iconic” model (...) of visual short-term memory. Second, the way in which subjects’ reports are used to show that specific unreported contents are nevertheless experienced on a phenomenal level is questioned, using evidence on gist and high-level categorical perceptual processing. It is concluded that sensory memory, properly understood, cannot provide the kind of visual content required to support a level of richly detailed phenomenal experience, or a pictorial account of perception. Finally, alternative ways of explaining visual richness are suggested. (shrink)

In this paper, I propose that those who reject higher-order theories of consciousness should not rule out the possibility of having conscious experiences that they cannot introspect. I begin by offering four arguments that such non-introspectible conscious experiences are possible. Next, I offer two arguments for thinking that we actually have such experiences. According to the first argument, it is unlikely that evolution would have furnished us with a faculty of introspection that worked flawlessly. According to the second argument, there (...) are many plausible potential sources of non-introspectible experiences. Given that all of these sources are at least somewhat plausible, it is fairly probable that we have some kind or other. Finally, I consider whether we might be justified in believing that we can introspect all of our conscious experiences if in fact we can. I show that current approaches to justifying belief in epiphenomenal qualia do not carry over. The upshot of these arguments is that we should be less certain that we really know what it feels like to be us. There may be much more to our experiences than we are aware of. (shrink)

This is a précis of my recent monograph John McDowell on Worldly Subjectivity: Oxford Kantianism Meets Phenomenology and Cognitive Sciences. I first describe the key question the book is trying to answer via understanding McDowell’s thinking and the general outline of it. The key question is a Kantian how-possible question, and the outline includes the distinction between first and second nature, the contrast between Cogito and Homo sapience, and how a minded human animal can be a perceiver, knower, thinker, speaker, (...) agent, person, and conceptual cum self-conscious being in the world. I then focus on two key notions of the subtitles—phenomenology and cognitive sciences—and explain how they figure in the text. After that, a chapter-by-chapter summary is provided, albeit selectively. This introductory piece ends with a prediction that McDowell’s works will still be widely discussed in the reasonable distant future. (shrink)

DETERMINACY is the claim that covert shifts in visual attention sometimes affect the determinacy of visual content (capital letters will distinguish the claim from the familiar word, 'determinacy'). Representationalism is the claim that visual phenomenology supervenes on visual representational content. Both claims are popular among contemporary philosophers of mind, and DETERMINACY has been employed in defense of representationalism. I claim that existing arguments in favor of DETERMINACY are inconclusive. As a result, DETERMINACY-based arguments in support of representationalism are not strong (...) ones. (shrink)

The Conscious Brain: How Attention Engenders Experience by Jesse J. Prinz. . ???aop.label???. doi: 10.1080/09515089.2013.838829.

The phenomenon of consciousness has received through the centuries a profusion of interpretations, engaging researchers across many disciplines. Nevertheless, consensus still floats at large. The aim of the present work is therefore twofold. Through the review of a selected number of existing proposals, it will first be considered the extents of their reciprocal compatibility, tentatively shaping an integrated, theoretical profile of consciousness. A new theory, the Endogenous Feedback Network will consequently be introduced which, besides being able to accommodate the main (...) tenets of the reviewed theories, appears able to compensate for the explanatory gaps they leave behind. The EFN proposes consciousness as the phenomenon emerging from a distinct neural network broadcasting the changes associated to mental activations across the brain. It additionally argues for the need to include a 5th element to Ned Block’s taxonomy that is, non-cognitive consciousness. (shrink)

The question of whether phenomenal consciousness is limited to the capacity of cognitive access remains a contentious issue in philosophy. Overflow theorists argue that the capacity of conscious experience outstrips the capacity of cognitive access. This paper demonstrates a resolution to the overflow debate is found in acknowledging a difference in phenomenological timing required by both sides. It makes clear that the “no overflow” view requires subjects to, at the bare minimum, generate an unconscious visual image of previously presented items (...) if it is to explain performance in the change detection paradigm. It then demonstrates that conscious imagery should support better task performance than unconscious imagery because of a necessary difference in representational strength. However, this contradicts empirical findings, and so a new argument for overflow is presented without requiring the premise that subjects need to obtain a specific phenomenology of presented items during change detection. (shrink)

Inattentional blindness is the failure to perceive salient stimuli presented at unattended locations. Whereas the behavioral manifestation of inattentional blindness has been investigated, the neural basis of this phenomenon has remained elusive. In the current study, event-related fMRI was used to identify the neural substrates associated with inattentional blindness. During central fixation, participants named colored digits presented at a peripheral location. On a subset of trials, an unexpected checkerboard circle was presented at the same eccentricity along with the colored digits (...) . Neural activity during inattentional blindness was observed in the prefrontal cortex. Together with previous findings, these results call into question the widespread view that activity in the prefrontal cortex reflects conscious processing. (shrink)

Event-related potential studies have attempted to discover the processes that underlie conscious visual perception by contrasting ERPs produced by stimuli that are consciously perceived with those that are not. Variability of the proposed ERP correlates of consciousness is considerable: the earliest proposed ERP correlate of consciousness coincides with sensory processes and the last one marks postperceptual processes. A negative difference wave called visual awareness negativity , typically observed around 200 ms after stimulus onset in occipitotemporal sites, gains strong support for (...) reflecting the processes that correlate with, and possibly enable, aware visual perception. Research suggests that the early parts of conscious processing can proceed independently of top-down attention, although top-down attention may modulate visual processing even before consciousness. Evidence implies that the contents of consciousness are provided by interactions in the ventral stream, but indispensable contributions from dorsal regions influence already low-level visual responses. (shrink)