The human eyes and brain, which have finite boundaries, create a ‘‘virtual’’ space within our central nervous system that interprets and perceives a space that appears boundless and infinite. Using insights from studies on the visual system, we propose a novel fast processing mechanism involving the eyes, visual pathways, and cortex where external vision is imperceptibly processed in our brain in real time creating an internal representation of external space that appears as an external view. We introduce the (...) existence of a three-dimension default space consisting of intrapersonal body space that serves as the framework where visual and non-visual sensory information is sensed and experienced. We propose that the thalamus integrates processed information from corticothalamic feedback loops and fills-in the neural component of 3D default space with an internal visual representation of external space, leading to the experience of visual consciousness. This visual space inherently evades perception so we have introduced three easy clinical tests that can assist in experiencing this visual space. We also review visual neuroanatomical pathways, binocular vision, neurological disorders, and visual phenomenon to elucidate how the representation of external visible space is recreated within the mind. (shrink)

It is commonly believed that human perceptual experiences can be, and usually are, multimodal. What is more, a stronger thesis is often proposed that some perceptual multimodal characters cannot be described simply as a conjunction of unimodal phenomenal elements. If it is the case, then a question arises: what is the additional mode of combination that is required to adequately describe the phenomenal structure of multimodal experiences? The paper investigates what types of audio–visual experiences have phenomenal character that cannot (...) be analysed as a mere conjunction of visual and auditory elements; and how can we properly characterise the required, additional mode of perceptual combination. Three main modes of combination are considered: instantiation, parthood, and grouping. It is argued that some phenomena involving intermodal relations, like spatial and temporal ventriloquism, can be analysed in terms of audio–visual, perceptual grouping. On the other hand, cases of intermodal binding need a different treatment. Experiences involving audio–visual binding should be analysed as experiences presenting objects or events which instantiate, or which have a proper part instantiating, both visually and auditorily determined properties. (shrink)

Milner and Goodale's influential account of the primate cortical visual streams involves a division of consciousness between them, for it is the ventral stream that has the responsibility for visual consciousness. Hence, the dorsal visual stream is a ‘zombie’ stream. In this article, I argue that certain information carried by the dorsal stream likely plays a central role in the egocentric spatial content of experience, especially the experience of visual spatial constancy. Thus, the dorsal (...) stream contributes to a pervasive feature of consciousness. (shrink)

When viewing a circular coin rotated in depth, it fills an elliptical region of the distal scene. For some, this appears to generate a two-fold experience, in which one sees the coin as simultaneously circular (in light of its 3D shape) and elliptical (in light of its 2D ‘perspectival shape’ or ‘p-shape’). An energetic philosophical debate asks whether the latter p-shapes are genuinely presented in perceptual experience (as ‘perspectivalists’ argue) or if, instead, this appearance is somehow derived or inferred from (...) experience (as ‘anti-perspectivalists’ argue). This debate, however, has largely turned on introspection. In a recent study, Morales, Bax, and Firestone (2020) aim to provide the first empirical test of this question. They asked subjects to find an elliptical coin seen face-on from a search array that also included a circular coin seen either face-on or at an angle. They found that subjects reacted more slowly when the distracting circle was seen at an angle, such that it’s p-shape matched that of the target ellipse. From this, they concluded that the similar p-shape between the ellipse and circle constituted a phenomenal similarity between the two, and thus that perspectivalism is true. We show that these results can also be explained by pre-attentive guidance by unconscious representations (in what follows, just “unconscious pre-attentive guidance”) and that this explanation is at least as plausible as one from phenomenal similarity. Thus, we conclude that the experiment does not support perspectivalism over anti-perspectivalism. (shrink)

Advances in neuroscience implicate reentrant signaling as the predominant form of communication between brain areas. This principle was used in a series of masking experiments that defy explanation by feed-forward theories. The masking occurs when a brief display of target plus mask is continued with the mask alone. Two masking processes were found: an early process affected by physical factors such as adapting luminance and a later process affected by attentional factors such as set size. This later process is called (...) masking by object substitution, because it occurs whenever there is a mismatch between the reentrant visual representation and the ongoing lower level activity. Iterative reentrant processing was formalized in a computational model that provides an excellent fit to the data. The model provides a more comprehensive account of all forms of visual masking than do the long-held feed-forward views based on inhibitory contour interactions. (shrink)

According to Milner and Goodale’s dual visual systems (DVS) theory, a division obtains between visual consciousness and motor action, in that the visual system producing conscious vision (the ventral stream) is distinct from the one guiding action (the dorsal stream). That there would be this division is often taken (by Andy Clark and others) to undermine the folk view on how consciousness and action relate. However, even if this division obtains, this leaves open the possibility (...) that con- scious ventral information is often transmitted to the uncon- scious dorsal stream and then used to guide action, a possibility seeming to preserve a significant role for consciousness in action. This article assesses this possibility. In course of doing so, we will review those arguments recently having been made against the DVS view on how visual consciousness and action relate (ones due to, e.g., Briscoe and Schwenkler, or Schenk and McIntosh). What we will find is that, if we properly analyze the data upon which these arguments are based, we are still left with the impression that the DVS view is largely correct; i.e., it is only rarely that visual experience guides action. (shrink)

Common sense suggests that visual consciousness is essential to skilled motor action, but Andy Clark—inspired by Milner and Goodale's dual visual systems theory—has appealed to a wide range of experimental dissociations to argue that such an assumption is false. Critics of Clark's argument contend that the content driving motor action is actually within subjects' experience, just not easily discovered. In this article, I argue that even if such content exists, it cannot be guiding motor action, since a (...) review of current visual neuroscience indicates that the visual brain areas producing conscious representations are distinct from those driving motor action. (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.

It has often been assumed that when we use vision to become aware of an object or event in our surroundings, this must be accompanied by a corresponding visual experience (i.e., seeing). The studies reported here show that this assumption is incorrect. When observers view a sequence of displays alternating between an image of a scene and the same image changed in some way, they often feel (or sense) the change even though they have no visual experience of (...) it. The subjective difference between sensing and seeing is mirrored in several behavioral differences, suggesting that these are two distinct modes of conscious visual perception. (shrink)

It is natural to assume that the fine-grained and highly accurate spatial information present in visual experience is often used to guide our bodily actions. Yet this assumption has been challenged by proponents of the Two Visual Systems Hypothesis , according to which visuomotor programming is the responsibility of a “zombie” processing stream whose sources of bottom-up spatial information are entirely non-conscious . In many formulations of TVSH, the role of conscious vision in action is limited to “recognizing (...) objects, selecting targets for action, and determining what kinds of action, broadly speaking, to perform” . Our aim in this study is to show that the available evidence not only fails to support this dichotomous view but actually reveals a significant role for conscious vision in motor programming, especially for actions that require deliberate attention. (shrink)

Perception, Action, and Consciousness: Sensorimotor Dynamics and Two Visual Systems is a state-of-the-art collection whose main goal is to explore, from an interdisciplinary perspective, the relationship between action and perception. A second goal of the volume is to investigate how perception and action interact specifically in the production of phenomenal awareness. In presenting and contrasting the major perspectives on the field, this volume marks a good sign of the progress being made on the nature of phenomenally conscious (...) class='Hi'>visual experience. By combining theoretical and empirical approaches it also contributes to the debate in key domains of the cognitive sciences .The book contains a useful editorial introduction written by the Editors and six sections further divided into fifteen chapters. In the first part of this review I briefly summarize the content of each section. Having offered an outline of the volume, I then turn my attention to the main theme of the collection, which is the dichotomy between action-oriented theories of perception and the two visual systems hypothesis and look at the dialectic underlying this debate. (shrink)

I raise a problem for common-factor theories of experience concerning the demonstrative thoughts we form on the basis of experience. Building on an insight of Paul Snowdon 1992, I argue that in order to demonstratively refer to an item via conscious awareness of a distinct intermediary the subject must have some understanding that she is aware of a distinct intermediary. This becomes an issue for common-factor theories insofar as it is also widely accepted that the general, pre-philosophical or ‘naïve’ view (...) of experience does not accept that in normal perceptual cases one is consciously aware of non-environmental (inner, mental) features. I argue then that the standard common-factor view of experience should be committed to attributing quite widespread referential errors or failures amongst the general, nonphilosophical populace – which seems an unattractively radical commitment. After clarifying the various assumptions I am making about experience and demonstrative thoughts, I consider a number of possible responses on behalf of the common-factor theorist. I finish by arguing that my argument should apply to any common-factor theory, not just avowedly ‘indirect' theories. (shrink)

Anosognosia for visual deficits—cases where significant visual deficits go unnoticed—challenges the view that our own conscious experiences are what we know best. We review these widespread and striking failures of awareness. Anosognosia can occur with total blindness, visual abnormalities induced by brain lesions, and eye diseases. We show that anosognosia for visual deficits is surprisingly widespread. Building on previous accounts, we introduce a framework showing how apparently disparate forms of anosognosia fit together. The central idea is (...) that, to notice a deficit, individuals need to form expectations about normal vision, compare expectations and visual input, and judge any mismatch at the metacognitive level. A failure in any of these three steps may lead to unawareness of visual deficits. (shrink)

A visual experience, as understood here, is a sensory event that is conscious, or like something to undergo. This chapter focuses on three issues concerning such experiences. The first issue is the so-called ‘transparency’ of experiences. The chapter distinguishes a number of different interpretations of the suggestion that visual experiences are ‘transparent’. It then discusses in what sense, if any, visual experiences are ‘transparent’, and what further conclusions one can draw from that. The second issue is which (...) properties we are presented with in visual experiences. It is widely accepted that we sometimes experience red for example. But exactly which properties do we sometimes visually experience, and which properties do we never visually experience? The third issue is which particulars, if any, we are presented with in visual experiences. Do we for example sometimes visually experience mind-independent particulars like trees? Do we sometimes visually experience mind-dependent, particular ‘sense-data’? (shrink)

The extensive involvement of nonconscious processes in human behaviour has led some to suggest that consciousness is much less important for the control of action than we might think. In this article I push against this trend, developing an understanding of conscious control that is sensitive to our best models of overt action control. Further, I assess the cogency of various zombie challenges—challenges that seek to demote the importance of conscious control for human agency. I argue that though nonconscious (...) contributions to action control are evidently robust, these challenges are overblown. (shrink)

Though the following problem is not explicitly raised by her, it seems sufficiently similar to an issue of pertinence to Akins's "Black and White and Color" (this volume) to merit the moniker, Akins's Problem : Can there be a visual experience devoid of both color phenomenology and black-and-white phenomenology? The point of the present paper is to draw from Akins's paper the materials needed to sketch a case for a positive answer to Akins's Problem. I am unsure about how (...) much of what follows Akins will want to endorse, but I hope this helps move us forward in our collective pursuit of a theory of visual consciousness. (shrink)

Whether visual perceptual consciousness is gradable or dichotomous has been the subject of fierce debate in recent years. If perceptual consciousness is gradable, perceivers may have less than full access to—and thus be less than fully phenomenally aware of—perceptual information that is represented in working memory. This raises the question: In virtue of what can a subject be less than fully perceptually conscious? In this chapter, we provide an answer to this question, according to which inexact categorizations (...) of visual input may result in a representation of the visual information in working memory that is less than fully available to the perceiver, and of which the perceiver is therefore less than fully phenomenally aware. The latter proposal is a natural extension of a theory of perception we have proposed in previous works, namely, the template tuning theory (TTT). We argue that although TTT is compatible with both gradable and dichotomous conceptions of perceptual consciousness, the available empirical evidence favours a gradable conception of perceptual consciousness. (shrink)

Consciousness and evolution are complex phenomena. It is sometimes thought that if adaptation explanations for some varieties of consciousness, say, conscious visual perception, can be had, then we may be reassured that at least those kinds of consciousness are not epiphenomena. But what if other varieties of consciousness, for example, dreams, are not adaptations? We sort out the connections among evolution, adaptation, and epiphenomenalism in order to show that the consequences for the nature and causal (...) efficacy of consciousness are not as dire as has sometimes been supposed. (shrink)

Neuroscience hasn’t shown how quite similar sensory circuits encode quite different colors and other qualia, nor how the unified pictorial form of images is encoded, nor how these codes yield conscious images. Neuroscience’s fixation here on cortical codes may be the culprit. Treating conscious images partly as retinal substances may avoid these problems. The evidence for conscious retinal images is that (a) the cortical codes for images are quite problematic, (b) injecting retinas with certain genes turns dichromats into trichromats without (...) cortical help, (c) retinas can discern colors by themselves without cortex, (d) retinal distortions appear in images but cortical distortions don’t, (e) retinal detectors support finely detailed colors, but V4 detectors don’t, due to their big receptive fields, (f) retinal activity has pictorial form, but viable cortical codes for pictorial form don’t exist. So, the colors and unified pictorial form of images arguably arise mainly across arrays of retinal detectors—not from abstract cortical codes. Images may be hidden in retinal activity beyond what EEGs show of it (cf. Strawson’s monism). Also, cortex refines these retinal images but cortical impairment (anesthesia, lesions, etc.) blocks awareness of them, for they’re no longer accessible to the mind’s subject-centered consciousness, resident in cortex. This proposal is largely testable and based in recent evidence. It avoids neuroscience’s elusive, problematic coded images and enigmatic explanations of how they become conscious. (shrink)

Integration information theories posit that the integration of information is necessary and/or sufficient for consciousness. In this paper, we focus on three of the most prominent information integration theories: Information Integration Theory, Global Workspace Theory, and Attended Intermediate-Level Theory. We begin by explicating each theory and key concepts they utilize. We then argue that the current evidence indicates that the integration of information is neither necessary nor sufficient for consciousness. Unlike GWT and AIR, IIT maintains that conscious experience (...) is both necessary and sufficient for consciousness. We present empirical evidence indicating that simple features are experienced in the absence of feature integration and argue that it challenges IIT’s necessity claim. In addition, we challenge IIT’s sufficiency claim by presenting evidence from hemineglect cases and amodal completion indicating that contents may be integrated and yet fail to give rise to subjective experience. Moreover, we present empirical evidence from subjects with frontal lesions who are unable to carry out simple instructions and argue that they are irreconcilable with GWT. Lastly, we argue that empirical evidence indicating that patients with visual agnosia fail to identify objects they report being conscious of present a challenge to AIR’s necessity claim. (shrink)

This paper argues that the many and various conceptions of consciousness propounded by cognitive scientists and philosophers can all be understood as constituted with reference to four fundamental sorts of criterion: epistemic (concerned with kinds of consciousness), semantic (dealing with orders of consciousness), physiological (reflecting states of consciousness), and pragmatic (seeking to capture types of consciousness). The resulting four-fold taxonomy, intended to be exhaustive, suggests that all of the distinct varieties of consciousness currently encountered (...) in cognitive neuroscience, the philosophy of mind, clinical psychology, and other related fields ultimately refer to a unified natural process, analysed under four general aspects. The proposed taxonomy will, it is hoped, possess sufficient clarity to serve as a sound theoretical framework for further scientific studies, and to count as a significant step in the direction of a properly formulated unified concept of consciousness. (shrink)

Does perceptual consciousness require cognitive access? Ned Block argues that it does not. Central to his case are visual memory experiments that employ post-stimulus cueing—in particular, Sperling's classic partial report studies, change-detection work by Lamme and colleagues, and a recent paper by Bronfman and colleagues that exploits our perception of ‘gist’ properties. We argue contra Block that these experiments do not support his claim. Our reinterpretations differ from previous critics' in challenging as well a longstanding and common view (...) of visual memory as involving declining capacity across a series of stores. We conclude by discussing the relation of probabilistic perceptual representations and phenomenal consciousness. (shrink)

In its classical form, epiphenomenalism is the view that conscious mental events have no physical effects: while physical events cause mental events, the opposite is never true. Unlike classical epiphenomenalism, contemporary forms do not hold that conscious men­ tal states always lack causal efficacy, only that they are epiphenomenal relative to certain kinds of action, ones we pre-theoretically would have thought consciousness to causally contribute to. Two of these contemporary, empirically based challenges to the efficacy of the mental are (...) the focus of this chapter. The first, originating in research by Libet, has been interpreted as showing that the neural events initiating voluntary actions precede our conscious willing of them, meaning the conscious will cannot be what causes them. The second challenge, originating in studies by Milner and Goodale, consist of instances in which the content of visual consciousness and motor action dissociate, casting doubt on the intuitive view that visual consciousness guides visually based motor action. (shrink)

Some philosophers—for example, Husserl, Alva Noë and Susanna Siegel—have claimed that the contents of visual sensations standardly include references to the later visual episodes that one would have under certain conditions. The current paper claims that there are no good reasons for accepting that view. Instead, it is argued that the conscious phenomena which have been cited as manifesting the presence within visual contents of references to ways that things would look in the course of later (...) class='Hi'>visual sensations are better explained in another manner: in terms of references within the contents of ordinary visual sensations to ways that things actually then look from various perspectives. (shrink)

David Milner and Melvyn Goodale’s dissociation hypothesis is commonly taken to state that there are two functionally specialized cortical streams of visual processing originating in striate (V1) cortex: a dorsal, action-related “unconscious” stream and a ventral, perception-related “conscious” stream. As Milner and Goodale acknowledge, findings from blindsight studies suggest a more sophisticated picture that replaces the distinction between unconscious vision for action and conscious vision for perception with a tripartite division between unconscious vision for action, conscious vision for perception, (...) and unconscious vision for perception. The combination excluded by the tripartite division is the possibility of conscious vision for action. But are there good grounds for concluding that there is no conscious vision for action? There is now overwhelming evidence that illusions and perceived size can have a significant effect on action (Bruno & Franz, 2009; Dassonville & Bala, 2004; Franz & Gegenfurtner, 2008; McIntosh & Lashley, 2008). There is also suggestive evidence that any sophisticated visual behavior requires collaboration between the two visual streams at every stage of the process (Schenk & McIntosh, 2010). I nonetheless want to make a case for the tripartite division between unconscious vision for action, conscious vision for perception, and unconscious vision for perception. My aim here is not to refute the evidence showing that conscious vision can affect action but rather to argue (a) that we cannot gain cognitive access to action-guiding dorsal stream representations, and (b) that these representations do not correlate with phenomenal consciousness. This vindicates the semi-conservative view that the dissociation hypothesis is best understood as a tripartite division. (shrink)

Consciousness and evolution are complex phenomena. It is sometimes thought that if adaptation explanations for some varieties of consciousness, say, conscious visual perception, can be had, then we may be reassured that at least those kinds of consciousness are not epiphenomena. But what if other varieties of consciousness, for example, dreams, are not adaptations? We sort out the connections among evolution, adaptation, and epiphenomenalism in order to show that the consequences for the nature and causal (...) efficacy of consciousness are not as dire as has sometimes been supposed. (shrink)

I argue for a manipulationist-mechanistic framework for content-NCC research in the case of visual consciousness (Bechtel 2008; Neisser 2012). Reference to mechanisms is common in the NCC research. Furthermore, recent developments in non-invasive brain stimulation techniques (NIBS) lend support to a manipulationist standpoint. The crucial question is to understand what is changed after manipulation of a brain mechanism. In the second part of the paper I review the literature on intentionalism, and argue that intervention on the neural mechanism (...) is likely to change the intentional content of consciousness. This urges us to shift from content-NCC to what I call “intentional mechanisms”. Such mechanisms, it is argued, should be understood as neural prerequisites of conscious visual experience. (shrink)

Let a "smooth experience" be an experience with perfectly gradual changes in phenomenal character. Consider, as examples, your visual experience of a blue sky or your auditory experience of a rising pitch. Do the phenomenal characters of smooth experiences have continuous or discrete structures? If we appeal merely to introspection, then it may seem that we should think that smooth experiences are continuous. This paper (1) uses formal tools to clarify what it means to say that an experience is (...) continuous or discrete, and (2) develops a discrete model of the phenomenal characters of smooth experiences. As a result, I'll argue that introspection leaves open whether smooth experiences are continuous or discrete. Yet I’ll also argue—perhaps surprisingly—that the discrete theory may better fit our introspective evidence. (shrink)

How should we characterize the nature of conscious occurrent thought? In the last few years, a rather unexplored topic has appeared in philosophy of mind: cognitive phenomenology or the phenomenal character of cognitive mental episodes. In this paper I firstly present the motivation for cognitive phenomenology views through phenomenal contrast cases, taken as a challenge for their opponents. Secondly, I explore the stance against cognitive phenomenology views proposed by Restrictivism, classifying it in two strategies, sensory restrictivism and accompanying states. On (...) the one hand, I problematize the role of attention adopted by sensory restrictivism and I present and discuss in detail an argument that defends the limitation of sensory phenomenology so as to explain the distinction between visual and cognitive mental episodes on the basis of immediate experience. On the other hand, I address accompanying states views by discussing the empirical studies of Hurlburt et al. (2006, 2008) that defend the existence of “unsymbolized thinking”. I present how they can be construed as evidence for cognitive phenomenology views and I dispel some problems that have been raised against its acceptance. I thus conclude that cognitive phenomenology views hold up well against the restrictivist positions considered. (shrink)

Visual phenomenology is highly elusive. One attempt to operationalize or to measure it is to use ‘cognitive accessibility’ to track its degrees. However, if Ned Block is right about the overflow phenomenon, then this way of operationalizing visual phenomenology is bound to fail. This thesis does not directly challenge Block’s view; rather it motivates a notion of cognitive accessibility different from Block’s one, and argues that given this notion, degrees of visual phenomenology can be tracked by degrees (...) of cognitive accessibility. Block points out that in the psychology literature, ‘cognitive accessibility’ is often regarded as either all or nothing. However, the notion motivated in the thesis captures the important fact that accessibility comes in degrees (consider the visual field from fovea the periphery). Different legitimate notions of accessibility might be adopted for different purposes. The notion of accessibility motivated here is weaker than Block’s ‘identification’ (2007) but is stronger than Tye’s ‘demonstration’ (2007). The moral drawn from the discussion of Block can be applied to the debate between Dretske and Tye on the speckled-hen style examples. Dretske’s view is even stronger than Block’s, but his arguments from various figures he provides do not support his conclusion since he does not have right ideas about fixation and attention. Tye’s picture is more plausible but his notion of accessibility is so weak that he reaches the excessive conclusion that accessibility overflows phenomenology. Three ramifications might be considered in the final part of the thesis. The first is the relation between this debate and the one concerning higher-order/same-order theories of consciousness. The second is about John McDowell’s early proposal about demonstrative concepts in visual experiences. The third is the relation between the interpretation of the Sperling case proposed here and McDowell new view of experiential contents, i.e., his story about how we carve out conceptual contents out of intuitional contents without falling pray to the Myth of the Given. (shrink)

Some recently popular accounts of perception account for the phenomenal character of perceptual experience in terms of the qualities of objects. My concern in this paper is with naturalistic versions of such a phenomenal externalist view. Focusing on visual spatial perception, I argue that naturalistic phenomenal externalism conflicts with a number of scientific facts about the geometrical characteristics of visual spatial experience.

Contemporary neuroscientific theories of consciousness are typically based on the study of vision and have neglected olfaction. Several of these (e.g. Global Workspace Theories, the Information Integration theory, and the various theories offered by Crick and Koch) claim that a thalamic relay is necessary for consciousness. Studies on olfaction and the olfactory system's anatomical structure show this claim to be incorrect, thus showing these theories to be either false or inadequate as general and comprehensive accounts of consciousness. (...) Attempts to rescue these theories by claiming that there is a structure in the olfactory system that is functionally equivalent to the thalamus in the visual system, such as the olfactory bulb or the olfactory cortex, are also shown to fail. If we wish to understand consciousness, we have to wake up and smell it. (shrink)

I argue that the neural realizers of experiences of trying are not distinct from the neural realizers of actual trying . I then ask how experiences of trying might relate to the perceptual experiences one has while acting. First, I assess recent zombie action arguments regarding conscious visual experience, and I argue that contrary to what some have claimed, conscious visual experience plays a causal role for action control in some circumstances. Second, I propose a multimodal account of (...) the experience of acting. According to this account, the experience of acting is a temporally extended, co-conscious collection of agentive and perceptual experiences, functionally integrated and structured both by multimodal perceptual processing as well as by what an agent is, at the time, trying to do. (shrink)

A reply to commentators -- Jake Beck, Nico Orlandi and Aaron Franklin, and Ian Phillips -- on our paper "Does perceptual consciousness overflow cognitive access?".

According to the Self-Location Thesis, certain types of visual experiences have self-locating and so first-person, spatial contents. Such self-locating contents are typically specified in relational egocentric terms. So understood, visual experiences provide support for the claim that there is a kind of self-consciousness found in experiential states. This paper critically examines the Self-Location Thesis with respect to dynamic-reflexive visual experiences, which involve the movement of an object toward the location of the perceiving subject. The main aim (...) of this paper is to offer an alternative interpretation of these cases which resists attributing them self-locating content, arguing for a replacement of the de se component with a non-conceptual equivalent of the indexical ‘here’. In its final section, the paper also considers an extension of the h-replacement account to cases of visual kinesthesis. (shrink)

According to higher-order theories of consciousness, a mental state is conscious only when represented by another mental state. Higher-order theories must predict there to be some brain areas (or networks of areas) such that, because they produce (the right kind of) higher-order states, the disabling of them brings about deficits in consciousness. It is commonly thought that the prefrontal cortex produces these kinds of higher-order states. In this paper, I first argue that this is likely correct, meaning that, (...) if some higher-order theory is true, prefrontal lesions should produce dramatic deficits in visual consciousness. I then survey prefrontal lesion data, looking for evidence of such deficits. I argue that no such deficits are to be found, and that this presents a compelling case against higher-order theories. (shrink)

This essay positions consciousness in the content field--also known as the visual field; it is an initial essay, providing a general overview of my thinking on this problem.

A general definition of consciousness is: ‘consciousness is a mental aspect of a system or a process, which is a conscious experience, a conscious function, or both depending on the context’, where the term context refers to metaphysical views, constraints, specific aims, and so on. One of the aspects of visual consciousness is the visual subjective experience (SE) or the first person experience that occurs/emerges in the visual neural-network of thalamocortical system (which includes dorsal (...) and ventral visual pathways and frontal cortex) during dynamic interactions among widely distributed neuronal groups. In this article, however, consciousness and SE are interchangeably used unless noted. Consciousness can be either access (reportable) or phenomenal consciousness. For access consciousness, the interactions are between feed forward stimulus dependent signals and fronto-parietal feedback attentional signals. The necessary ingredients for access (reportable) consciousness are (i) wakefulness, (ii) reentrant interactions among neural populations, (iii) fronto-parietal and thalamic-reticular-nucleus attentional signals that modulate consciousness, (iv) working memory that retains information for consciousness, (v) stimulus at or above threshold level, and (vi) neural-network proto-experiences (PEs) that are superposed SEs embedded in a neural-network. Attention and the ability to report are not necessary for phenomenal consciousness. The neural source for the arousal system is the ascending reticular activating system in the brain stem, which brings the thalamocortical neural networks to wakeful state as a baseline for consciousness to occur. Reentrant interactions among neural populations bind stimulus attributes (such as location and features) and entail consciousness. Attention could be the results of reentry and competitive interactions, and modulates the stimulus related feed forward signal and consciousness. The ‘sources’ of attention may be thalamic reticular nucleus for bottom-up or frontal cortex for top-down direction. The ‘target’ of visual attention is ‘V4/V8/VO’ for Red-Green (R-G) channel. The neural correlates of the psychophysical entity R-G channel appear to be ‘V4/V8/VO’-neural-network (retina → LGN ↔ V1 ↔ V2 ↔ ‘V4/V8/VO’, and areas for attention, memory, and wakefulness). The psychophysical Red-Green Channel, its neurophysiological correlates V4/V8/VO-neural-network, and related experience (such as redness) are integrated. The dual-aspect-dual-mode PE-SE framework (Vimal, J Integr Neurosci 7:49–73, 2008) was used to address the explanatory gap problem of materialism. Neural-network and related SEs are the results of the co-evolution and co-development of the material aspect (mass, charge, spin, force, quanta, and space-time) and the mental aspect of fundamental particles (strings or elementary particles (fermions and bosons)). Their mental aspects are considered as the carriers of superposed multiple possible experiences (SEs/PEs) in unexpressed form. These possibilities are actualized when neural-networks are formed via neural Darwinism, and a specific SE is selected by a matching process when the necessary ingredients of consciousness/SE are satisfied. A simple experimental design is suggested to address the necessary and sufficient attributes of consciousness. (shrink)

This paper aims to clarify the relationship between consciousness and attention through theoretical considerations about evolution. Specifically, we will argue that the empirical findings on attention and the basic considerations concerning the evolution of the different forms of attention demonstrate that consciousness and attention must be dissociated regardless of which definition of these terms one uses. To the best of our knowledge, no extant view on the relationship between consciousness and attention has this advantage. Because of this (...) characteristic, this paper presents a principled and neutral way to settle debates concerning the relationship between consciousness and attention, without falling into disputes about the meaning of these terms. A decisive conclusion of this approach is that extreme views on the relationship between consciousness and attention must be rejected, including identity and full dissociation views. There is an overlap between the two within conscious attention, but developing a full understanding of this mechanism requires further empirical investigations. (shrink)

Judgments of visual resemblance (‘A looks like B’), unlike other judgments of resemblance, are often induced directly by visual experience. What is the nature of this experience? We argue that the visual experience that prompts a subject looking at A to judge that A looks like B is a visual experience of B. After elucidating this thesis, we defend it, using the ‘phenomenal contrast’ method. Comparing our account to competing accounts, we show that the phenomenal contrast (...) between a visual experience that induces the judgment that A looks like B, and a visual experience that does not induce this judgment, is best explained by the fact that the former visually represents B, whereas the latter does not. (shrink)

Sydney Shoemaker, developing an idea of Wittgenstein’s, argues that we are immune to error through misidentification relative to the first-person pronoun. Although we might be liable to error when “I” (or its cognates) is used as an object, we are immune to error when “I” is used as a subject (as when one says, “I have a toothache”). Shoemaker claims that the relationship between “I” as-subject and the mental states of which it is introspectively aware is tautological: when, say, we (...) judge that “I feel pain,” we are tautologically aware that feels pain is instantiated and that it is instantiated in oneself. Moreover, he contends that this relationship holds not just for bodily sensations, but also for the sense of agency and for visual perception. But we deny that this relationship is tautological; instead, we treat Shoemaker’s principle (IEM) as a hypothesis. We then proceed to show that certain pathological states and experimentally-induced illusions can be adduced to show that IEM describes not a necessary relationship but a contingent relationship, one that sometimes fails to obtain. That we are not immune to error in the way Shoemaker describes has grave consequences for many aspects of his ideas concerning the first-person perspective. In the course of arguing that these empirical phenomena count against IEM, we also show that not only can the content of conscious experience be misrepresented, so too can the subject: that is, not only can the what of conscious experience be misrepresented, so too can the who. (shrink)

Conscious experiences in infants remain poorly understood. In this NeuroView, Passos-Ferreira discusses recent evidence for and against consciousness in newborn babies. She argues that the weight of evidence from neuroimaging and behavioral studies supports the thesis that newborn infants are conscious.

In this chapter, we discuss a selection of current views of the neural correlates of consciousness (NCC). We focus on the different predictions they make, in particular with respect to the role of prefrontal cortex (PFC) during visual experiences, which is an area of critical interest and some source of contention. Our discussion of these views focuses on the level of functional anatomy, rather than at the neuronal circuitry level. We take this approach because we currently understand more (...) about experimental evidence at this coarse level and because these results are appropriate for arbitrating between current theoretical frameworks. We discuss the Two-Visual-Systems Hypothesis (Milner & Goodale 1995; 2006), Local Recurrency (Lamme 2010; Lamme 2006), Higher Order (Lau 2008; Lau & Rosenthal 2011) and Global Workspace theories (Baars 1997; Baars 2005; Dehaene & Naccache 2001; Dehaene 2014). Despite the apparent stark differences between conscious and unconscious perceptual processing, available evidence suggests that their neural substrates must be largely shared. This indicates that the difference in neural activity between conscious and unconscious perceptual processing is likely to be subtle and highly specialized. We argue that current experimental evidence about the involvement of specific activity in prefrontal cortex supports the higher order neural theory of consciousness. In consequence, imaging techniques that focus only on marked differences between conscious and unconscious level of activity are likely to be insensitive to the relevant neural activity patterns that underlie conscious experiences. Finally, it follows from the evidence we discuss that the functional advantages of conscious over unconscious perceptual processing may be more limited than commonly thought. (shrink)

One of the most compelling questions still unanswered in neuroscience is how consciousness arises. In this article, we examine visual processing, the parietal lobe, and contralateral neglect syndrome as a window into consciousness and how the brain functions as the mind and we introduce a mechanism for the processing of visual information and its role in consciousness. We propose that consciousness arises from integration of information from throughout the body and brain by the thalamus (...) and that the thalamus reimages visual and other sensory information from throughout the cortex in a default three-dimensional space in the mind. We further suggest that the thalamus generates a dynamic default three-dimensional space by integrating processed information from corticothalamic feedback loops, creating an infrastructure that may form the basis of our consciousness. Further experimental evidence is needed to examine and support this hypothesis, the role of the thalamus, and to further elucidate the mechanism of consciousness. (shrink)

We contrast two theoretical positions on the relation between phenomenal and access consciousness. First, we discuss previous data supporting a mild Overflow position, according to which transient visual awareness can overflow report. These data are open to two interpretations: (i) observers transiently experience specific visual elements outside attentional focus without encoding them into working memory; (ii) no specific visual elements but only statistical summaries are experienced in such conditions. We present new data showing that under data-limited (...) conditions observers cannot discriminate a simple relation (same versus different) without discriminating the elements themselves and, based on additional computational considerations, we argue that this supports the first interpretation: summary statistics (same/different) are grounded on the transient experience of elements. Second, we examine recent data from a variant of ‘inattention blindness’ and argue that contrary to widespread assumptions, it provides further support for Overflow by highlighting another factor, ‘task relevance’, which affects the ability to conceptualize and report (but not experience) visual element. (shrink)

Local Recurrency Theory (LR) holds that recurrent loops of neural activity localized to the visual cortex are necessary and sufficient for visual consciousness (if certain background conditions obtain). LR’s popularity has recently waned in favor of theories holding that higher-level types of processing are necessary for consciousness (for example, the Global Neuronal Workspace Theory and Higher-order Theory). This has been in part because of empirical evidence thought to disconfirm LR. However, these competing theories now face challenges (...) of their own, often coming in the form of evidence showing that higher-level brain areas (that is, in the prefrontal cortex) are probably not essential for consciousness. Given growing challenges to LR's competitors, it would be timely to re-assess the prospects for LR. This article carries out such an investigation, first laying out the theory precisely, then going on to survey the evidence presented against it. What will be found is that none of the evidence necessarily undermines LR, but instead just fosters its theoretical enrichment. The overall conclusion: LR remains among our most promising neuroscientific theories of visual consciousness. (shrink)

For almost half a century dual-stream advocates have vigorously defended the view that there are two functionally specialized cortical streams of visual processing originating in the primary visual cortex: a ventral, perception-related ‘conscious’ stream and a dorsal, action-related ‘unconscious’ stream. They furthermore maintain that the perceptual and memory systems in the ventral stream are relatively shielded from the action system in the dorsal stream. In recent years, this view has come under scrutiny. Evidence points to two overlapping action (...) pathways: a dorso-dorsal pathway that calculates features of the object to be acted on, and a ventro-dorsal pathway that transmits stored information about skilled object use from the ventral stream to the dorso-dorsal pathway. This evidence suggests that stored information may exert significantly more influence on visually guided action than hitherto assumed. I argue that this, in turn, supports the notion of skilled automatic action that is nonetheless agential. My focus here will be on actions influenced by implicit biases (stereotypes/prejudices). Action that is biased in this way, I argue, is in an important sense intentional and agential. (shrink)

Given the ever-present subject of consciousness wherever consciousness is, it is peculiar that consciousness researchers often mention mental states as if they are conscious independently of being the conscious states of someone [1, p. 132]. We refer to visual perceptions that become conscious, when in reality no one has ever studied mere conscious visual perceptions. What are studied are visual perceptions belonging to conscious human or animal subjects; it is the subjects who are conscious (...) of visual stimuli, not the visual perceptions. I do not know all the reasons why conscious subjects are rarely mentioned in consciousness science, but one could be pragmatic. Explaining the mysterious jump from the nonconscious nuts and bolts of neurons to the aurora borealis of consciousness is a hard problem. But it is an easy problem compared to explaining the emergence of a single conscious subject from the human brain’s 86 billion neurons [cf. 5]. Perhaps it is more practically realistic to solve the less hard problem before attempting to solve the harder hard problem. On the other hand, if we ignore a necessary condition for the presence of consciousness, our explanations of it could be plagued by inadequacy. And how can we explain our whole data set regarding consciousness if we neglect the most fundamental aspect of the data? (shrink)

It is suggested that the relationship between visual attention and conscious visual experience can be simplified by distinguishing different aspects of both visual attention and visual experience. A set of principles is first proposed for any possible taxonomy of the processes involved in visual attention. A particular taxonomy is then put forward that describes five such processes, each with a distinct function and characteristic mode of operation. Based on these, three separate kinds—or possibly grades—of conscious (...) visual experience can be distinguished, each associated with a particular combination of attentional processes. (shrink)

Working memory, an important posit in cognitive science, allows one to temporarily store and manipulate information in the service of ongoing tasks. Working memory has been traditionally classified as an explicit memory system – that is, as operating on and maintaining only consciously perceived information. Recently, however, several studies have questioned this assumption, purporting to provide evidence for unconscious working memory. In this paper, we focus on visual working memory and critically examine these studies as well as studies of (...) unconscious perception that seem to provide indirect evidence for unconscious working memory. Our analysis indicates that current evidence does not support an unconscious working memory store, though we offer independent reasons to think that working memory may operate on unconsciously perceived information. (shrink)