In the past decade, the notion of a neural correlate of consciousness (or NCC) has become a focal point for scientific research on consciousness (Metzinger, 2000a). A growing number of investigators believe that the first step toward a science of consciousness is to discover the neural correlates of consciousness. Indeed, Francis Crick has gone so far as to proclaim that ‘we … need to discover the neural correlates of consciousness.… For this task the primate visual system seems especially attractive.… No (...) longer need one spend time attempting … to endure the tedium of philosophers perpetually disagreeing with each other. Con- sciousness is now largely a scientific problem’ (Crick, 1996, p. 486).2 Yet the question of what it means to be a neural correlate of consciousness is actually far from straightforward, for it involves fundamental empirical, methodological, and _philosophical _issues about the nature of consciousness and its relationship to the brain. Even if one assumes, as we do, that states of consciousness causally depend on states of the brain, one can nevertheless wonder in what sense there is, or could be, such a thing as a neural correlate of consciousness. (shrink)

Our eyes, bodies, and perspectives are constantly shifting as we observe the world. Despite this, we are very good at distinguishing between self-caused visual changes and changes in the environment: the world appears mostly stable despite our visual field moving around. This, it seems, also occurs when we are dreaming. As we visually investigate the dream environment, we track moving objects with our dream eyes, examine objects, and shift focus. These movements, research suggests, are reflected in the rapid movements or (...) saccades of our sleeping eyes. Do we really see the dream world in the same way that we see the real world? If we do, how could dreaming, usually assumed to be mind-generated hallucinations, replicate such an experience? This problem would be deflated if dreams are not hallucinations at all, but rather imagination, illusion or simply unrealistic. I argue that imagination and illusion views do not satisfactorily explain away the problem of vision and action in sleep. The imagination model is not a complete description of dreaming that is consistent with empirical research, and it is unlikely that the visual dream world is an illusion. Given that the dreaming visual experience is most likely active, hallucinatory, and at times a realistic world simulation, there are important implications for our understanding of visual perception and its relationship to movement. Evidence suggests that our dream eyes investigate the dream world as our waking eyes investigate the waking world. If changes to the unconsciously generated dream environment are perceived as external and unintentional while dream body movements are perceived as self-generated and intentional, current theory of visual perception may have to be expanded to account for how the dreaming mind generates a stable world in which we track and visually explore mind-generated objects. (shrink)

Do we see more than we can report? Psychologists and philosophers have been hotly debating this question, in part because both possibilities are supported by suggestive evidence. On one hand, phenomena such as inattentional blindness and change blindness suggest that visual awareness is especially sparse. On the other hand, experiments relating to iconic memory suggest that our in-the-moment awareness of the world is much richer than can be reported. Recent research has attempted to resolve this debate by showing that observers (...) can accurately report the color diversity of a quickly flashed group of letters, even for letters that are unattended. If this ability requires awareness of the individual letters’ colors, then this may count as a clear case of conscious awareness overflowing cognitive access. Here we explored this requirement directly: can we perceive ensemble properties of scenes even without being aware of the relevant individual features? Across several experiments that combined aspects of iconic memory with measures of change blindness, we show that observers can accurately report the color diversity of unattended stimuli, even while their self-reported awareness of the individual elements is coarse or nonexistent — and even while they are completely blind to situations in which each individual element changes color mid-trial throughout the entire experiment. We conclude that awareness of statistical properties may occur in the absence of awareness of individual features, and that such results are fully consistent with sparse visual awareness. (shrink)

The topic of this paper is phenomenology. How should we think of phenomenology – the discipline or activity of investigating experience itself – if phenomenology is to be a genuine source of knowledge? This is related to the question whether phenomenology can make a contribution to the empirical study of human or animal experience. My own view is that it can. But only if we make a fresh start in understanding what phenomenology is and can be.

The idea that attention is necessary for consciousness (the “Necessity Thesis”) is frequently advocated by philosophers and psychologists alike. Experiments involving inattentional and change blindness are thought to support the Necessity Thesis, but they do so only if subjects failing to notice the target stimulus are also not conscious of it. This article uses commonsense phenomenological observations supplemented with empirical data to argue that some subjects failing to notice the target stimulus nonetheless experience its color. Since subjects not noticing the (...) target are commonly assumed to be not attending to it, these scenarios would be instances of consciousness without attention: instead of inattentional and change blindness supporting the Necessity Thesis, they would present counterexamples to it. (shrink)

This paper investigates a new species ofskeptical reasoning about visual experience that takesits start from developments in perceptual science(especially recent work on change blindness andinattentional blindness). According to thisskepticism, the impression of visual awareness of theenvironment in full detail and high resolution isillusory. I argue that the new skepticism depends onmisguided assumptions about the character ofperceptual experience, about whether perceptualexperiences are ''internal'' states, and about how bestto understand the relationship between a person''s oranimal''s perceptual capacities and the brain-level orneural processes (...) on which they depend. I propose aconception of perceptual experience as a form ofskillful engagement with the environment on the partof the whole person or animal. (shrink)

This paper is concerned with the question of whether mature human experience is thoroughly conceptual, or whether it involves non-conceptual elements or layers. It has two central goals. The first goal is methodological. It aims to establish that that question is, to a large extent, an empirical question. The question cannot be answered by appealing to purely a priori and transcendental considerations. The second goal is to argue, inter alia by relying on empirical findings, that the view known as ‘state-conceptualism’ (...) is false. We will argue that our experiences do involve non-conceptual elements. That is, a subject may enjoy an experience with a particular phenomenal aspect, without possessing the concept needed for the specification of the content of that aspect, and moreover, without being able to acquire that concept upon having that experience. (shrink)

Plausibly, any adequate theory of perception must (a) solve what Alva Noë calls 'the problem of perceptual presence,' and (b) do justice to the direct realist idea that what is given in perception are garden-variety spatiotemporal particulars. This paper shows that, while Noë's sensorimotor view arguably satisfies the first of these conditions, it does not satisfy the second. Moreover, Noë is wrong to think that a naïve realist approach to perception cannot handle the problem of perceptual presence. Section three of (...) this paper develops a version of naïve realism that meets both of the adequacy conditions above. This paper thus provides strong considerations in favor of naïve realism. (shrink)

This paper aims to conceptualize the phenomenology of attentional experience as ‘embodied attention.’ Current psychological research, in describing attentional experiences, tends to apply the so-called spotlight metaphor, according to which attention is characterized as the illumination of certain surrounding objects or events. In this framework, attention is not seen as involving our bodily attitudes or modifying the way we experience those objects and events. It is primarily conceived as a purely mental and volitional activity of the cognizing subject. Against this (...) view, the phenomenology of Maurice Merleau-Ponty shows that attention is a creative activity deeply linked with bodily movements. This paper clarifies and systematizes this view and brings it into dialogue with current empirical findings as well as with current theoretical research on embodied cognition. By doing this, I spell out three main claims about embodied attention: the transcendentalism of embodiment for attention, the bodily subjectivity of attention, and the creativity of embodied attention. (shrink)

The main idea of this book is that perceiving is a way of acting. Perception is not something that happens to us, or in us. It is something we do. Think of a blind person tap-tapping his or her way around a cluttered space, perceiving that space by touch, not all at once, but through time, by skillful probing and movement. This is, or at least ought to be, our paradigm of what perceiving is. The world makes itself available to (...) the perceiver through physical movement and interaction. In this book I argue that all perception is touch-like in this way: perceptual experience acquires content thanks to our possession of bodily skills. What we perceive is determined by what we do ; it is determined by what we are ready to do. In ways I try to make precise, we enact our perceptual experience; we act it out. (shrink)

The paper rejects the claim that phenomena such as change and inattentional blindness show that perceptual representations are inaccurate or that a radical overhaul of our traditional picture of perception is required. The paper rejects in particular the sensorimotor theory of perception, which denies that there are any perceptual representations. It further argues that the degree of resolution of perceptual experience relevant to assessing its accuracy is determined by our use of it in standard conditions, and that the integration of (...) behavior with perceptual representation shows that it is by and large as accurate as its degree of resolution requires. (shrink)

In a series of three experiments, we explored the nature of implicit representations in change blindness . Using 3 × 3 letter arrays, we asked subjects to locate changes in paired arrays separated by 80 ms ISIs, in which one, two or three letters of a row in the second array changed. In one testing version, a tone followed the second array, signaling a row for partial report . In the other version, no PR was required. After Ss reported whether (...) a change had been detected and the PR had been completed , they were asked to identify a degraded letter trigram that was either novel, or from a previously shown row . Our findings indicate that when CB occurs, both the pre-change and post-change stimulus information primes despite its unavailability to consciousness. Surprisingly, findings also indicate that when change detection occurs only the post-change information primes. (shrink)

Classic change blindness is the phenomenon where seemingly obvious changes which coincide with visual disruptions (such as blinks or brief blanks) go unnoticed by an attentive observer. Some early work into the causes of classic change blindness suggested that any pre-change stimulus representation is overwritten by a representation of the altered post-change stimulus, preventing change detection. However, recent work revealed that even when observers do maintain memory representations of both the pre- and post-change stimulus states, they can still miss the (...) change, suggesting that change blindness can also arise from a failure to compare the stored representations. Here we study slow change blindness, a different but related phenomenon that occurs even in the absence of visual disruptions when the change occurs sufficiently slowly, to determine whether it could be explained by conclusions from classic change blindness. Across three different slow change blindness experiments we found that observers, who consistently failed to notice the change, had access to at least two memory representations of the changing display. One representation was precise but short-lived: a relatively detailed representation of the more recent states of slow-change display, but fragile. The other representation lasted longer but was fairly general: stable but too coarse to differentiate the various stages of the changing display. These findings suggest that although multiple representations are formed, the failure to compare hypothesis might not explain slow change blindness; even if a comparison were made, the representations formed would be either too sparse (longer term stores) or too fragile (short-lived stores) for such a comparison to be informative about a change. (shrink)

A significant impediment to the study of perceptual consciousness is our dependence on simplistic ideas about what experience is like. This is a point that has been made by Wittgenstein, and by philosophers working in the Phenomenological Tradition, such as Husserl and Merleau-Ponty. Importantly, it is an observation that has been brought to the fore in recent discussions of consciousness among philosophers and cognitive scientists who have come to feel the need for a more rigorous phenomenology of experience. The central (...) thought of this paper is that art can make a needed contribution to the study of perceptual consciousness. The work of some artists can teach us about perceptual consciousness by furnishing us with the opportunity to have a special kind of reflective experience. In this way, art can be a tool for phenomenological investigation. The paper focuses on the work of Richard Serra and offers a comparison of his work with that of Tony Smith. (shrink)

Plain phenomenology explains theoretically salient mental or psychological distinctions with an appeal to their first-person applications. But it does not assume that warrant for such first-person judgment is derived from an explanatory theory constructed from the third-person perspective. Discussions in historical phenomenology can be treated as plain phenomenology. This is illustrated by a critical consideration of Brentano’s account of consciousness, drawing on some ideas in early Husserl. Dennett’s advocacy of heterophenomenology on the grounds of its supposed “neutrality” does not show (...) it is preferable to plain phenomenology. In fact the latter is more neutral in ways we ought to want, and permits a desirable use of first-person reflection that finds no place in the former. (shrink)

Recently, a number of experiments have emphasized the degree to which subjects fail to detect large changes in visual scenes. This finding, referred to as “change blindness,” is often considered surprising because many people have the intuition that such changes should be easy to detect. Levin, Momen, Drivdahl, and Simons documented this intuition by showing that the majority of subjects believe they would notice changes that are actually very rarely detected. Thus subjects exhibit a metacognitive error we refer to as (...) “change blindness blindness.” Here, we test whether CBB is caused by a misestimation of the perceptual experience associated with visual changes and show that it persists even when the pre- and postchange views are separated by long delays. In addition, subjects overestimate their change detection ability both when the relevant changes are illustrated by still pictures, and when they are illustrated using videos showing the changes occurring in real time. We conclude that CBB is a robust phenomenon that cannot be accounted for by failure to understand the specific perceptual experience associated with a change. (shrink)

Our recent opinion article [1] examined what change blindness can and cannot tell us about visual representations. Among other things, we argued that change blindness can tell us a lot about how visual representations can be used, but little about their extent. We and others found the ‘sparse representations’ view appealing (and still do), and initially made the overly strong claim that change blindness supports the conclusion of sparse representations [2,3]. We wrote our article because change blindness continues to be (...) taken as evidence for sparse – or even absent – representations, and we used O’Regan and Noë’s influential paper [4] as an example. However, as has been noted for some time [5–8], this conclusion is logically flawed: lack of ability need not be caused by lack of representation. (shrink)

In three experiments, we investigated the priming effects induced by an image change on a successive animate/inanimate decision task. We studied both perceptual and conceptual priming effects, under correct change detection and change blindness . Under correct change detection, we found larger positive priming effects on congruent trials for probes representing animate entities than for probes representing artifactual objects. Under CB, we found performance impairment relative to a “no-change” baseline condition. This inhibition effect induced by CB was modulated by the (...) semantic congruency between the changed item and the probe in the case of probe images, but not for probe words. We discuss our results in the context of the literature on the negative priming effect. (shrink)

A theory of perception must be capable of explaining the full range of conscious perception, including amodal perception. In amodal perception we perceive the world to contain physical features that are not directly detectable by the sensory receptors. According to the active-externalist theory of perception, amodal perception depends on active engagement with perceptual objects. This paper focuses on amodal visual perception and presents a counter-example to the idea that active-externalism can account for amodal perception. The counterexample involves the experience of (...) so-called ‘impossible objects’, objects experienced in perceptual character as having geometrical properties that no physically real object can have. (shrink)

In the past two decades a number of arguments have been given in favor of the possibility of phenomenal consciousness without attentional access, otherwise known as phenomenal overflow. This paper will show that the empirical data commonly cited in support of this thesis is, at best, ambiguous between two equally plausible interpretations, one of which does not posit phenomenology beyond attention. Next, after citing evidence for the feature-integration theory of attention, this paper will give an account of the relationship between (...) consciousness and attention that accounts for both the empirical data and our phenomenological intuitions without positing phenomenal consciousness beyond attention. Having undercut the motivations for accepting phenomenal overflow along with having given reasons to think that phenomenal overflow does not occur, I end with the tentative conclusion that attention is a necessary condition for phenomenal consciousness. -/- . (shrink)

Three commitments guide Dennett’s approach to the study of consciousness. First, an ontological commitment to materialist monism. Second, a methodological commitment to what he calls ‘heterophenomenology.’ Third, a ‘doxological’ commitment that can be expressed as the view that there is no room for a distinction between a subject’s beliefs about how things seem to her and what things actually seem to her, or, to put it otherwise, as the view that there is no room for a reality/appearance distinction for consciousness. (...) We investigate how Dennett’s third doxological commitment relates to his first two commitments and whether its acceptance should be seen as a mere logical consequence of acceptance of the first two. We will argue that this is not the case, that Dennett’s doxological commitment is in need of independent motivation, and that this independent motivation is not forthcoming. (shrink)

Several recent findings support the notion that changes in the environment can be implicitly represented by the visual system. S. R. Mitroff, D. J. Simons, and S. L. Franconeri (2002) challenged this view and proposed alternative interpretations based on explicit strategies. Across 4 experiments, the current study finds no empirical support for such alternative proposals. Experiment 1 shows that subjects do not rely on unchanged items when locating an unaware change. Experiments 2 and 3 show that unaware changes affect performance (...) even when they occur at an unpredictable location. Experiment 4 shows that the unaware congruency effect does not depend simply on the pattern of the final display. The authors point to converging evidence from other methodologies and highlight several weaknesses in Mitroff et al.’s theoretical arguments. It is concluded here that implicit representation of change provides the most parsimonious explanation for both past and present findings. (shrink)

In my dissertation I critically survey existing theories of time consciousness, and draw on recent work in neuroscience and philosophy to develop an original theory. My view depends on a novel account of temporal perception based on the notion of temporal qualities, which are mental properties that are instantiated whenever we detect change in the environment. When we become aware of these temporal qualities in an appropriate way, our conscious experience will feature the distinct temporal phenomenology that is associated with (...) the passing of time. The temporal qualities model of perception makes two predictions about the mechanisms of time perception; one that time perception is modality specific and the other that it can occur without awareness. My argument for this view partially depends on a number of psychophysical experiments that I designed and implemented myself and which investigate subjective time distortions caused by looming visual stimuli. These results show that the mechanisms of conscious experience of time are distinct from the mechanisms of time perception, as my theory of temporal qualities predicts. (shrink)

The commentators do not contest the target article's claim that there is no compelling evidence of theory of mind in primates, and recent empirical studies further support this view. If primates lack theory of mind, they may still have other behavior control mechanisms that are adaptive in complex social environments. The Somatic Marker Mechanism (SMM) is a candidate, but the SMM hypothesis postulates a much weaker effect of natural selection on social cognition than the theory of mind hypothesis (on inputs (...) to cognitive mechanisms, not on the mechanisms themselves), and there is currently no evidence that it is specific to social stimuli or to primates. “Two Guesser” training would make the goggles test too chauvinistic, and in its current form the goggles problem could not be solved by physical matching because, while wearing goggles, an individual cannot see itself seeing. (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.

Past research has repeatedly documented the close relationship between visual attention and awareness. Most recently, research exploring change blindness, inattentional blindness, repetition blindness, and the attentional blink has converged on the conclusion that attention to one aspect of a scene or event may lead to a highly circumscribed awareness of only the specific information attended, while other information, even that which is spatially or temporally nearby can go completely unnoticed. In the present report, we extend these observations to the dynamic (...) allocation of attention during a well-structured meaningful event. In two experiments, subjects viewed brief videos of simple events and were told to pay close attention to them. During the events, an unexpected disruption consisting of a brief low spatial frequency motion field occurred. Despite intensive questioning and opportunities for recognition, the majority of subjects reported no awareness of 200, 400, or 600 ms disruptions. In a second experiment, blank-screen disruptions were added, and these resulted in no increase in detection. We conclude that visual attention may result in far more transitory awareness of visual information than previously appreciated. (shrink)

Soul beliefs are universal among religious folk but vary tremendously from culture to culture, In fact, in tribal societies without formal religious dogmas, soul beliefs can vary from individual to individual. A review of notions regarding the soul (or souls) amongst tribal and post-tribal societies does evidence, nonetheless, a recurring pattern of focus on the soul envisaged as the vital life energy of the body and/or as encapsulating one of more mental faculties. Not surprisingly, theories as to the psychological basis (...) for soul belief vary as well, but a strong case can be advanced that at its core, soul belief is about the essence of the self, which involves the psychological process of ipseity. (shrink)

Psychophysical studies of change blindness indicate that, at any instant, human observers are aware of detail in few parts of the visual field. Such results suggest, to some theorists, that human vision reconstructs only a few portions of the visual scene and that, to bridge the resulting representational gaps, it often lets physical objects serve as their own short-term memory. We propose that human vision reconstructs no portion of the visual scene, and that it never lets physical objects serve as (...) their own short-term memory. (shrink)

The goal of this study is to characterize observers’ abilities to detect gradual changes and to explore putative dissociations between conscious experience of change and behavioral adaptation to a changing stimulus. We developed a new experimental paradigm in which, on each trial, participants were shown a dot pattern on the screen. Next, the pattern disappeared and participants had to reproduce it. In some conditions, the target pattern was incrementally rotated over successive trials and participants were either informed or not of (...) this change. We analyzed both awareness of the changes and the dynamics of behavioral adaptation, in a way that makes it possible to assess both variability and accuracy as they change over time. Results indicate a dissociation between change awareness and behavioral adaptation to the changes, and support the notion that unconscious representations of visual stimuli are more precise and detailed than previously suggested. We discuss the implications of these results for theories of change detection. (shrink)

Models of memory in cognitive science and philosophy have traditionally explained human remembering in terms of storage and retrieval. This tendency has been entrenched by reliance on computationalist explanations over the course of the twentieth century; even research programs that eschew computationalism in name, or attempt the revision of traditional models, demonstrate tacit commitment to computationalist assumptions. It is assumed that memory must be stored by means of an isomorphic trace, that memory processes must divide into conceptually distinct systems and (...) phases, and that human remembering consists in inner, cognitive processes that are implemented by distinct neural processes. This dissertation draws on recent empirical work, and on philosophical arguments from Ludwig Wittgenstein and others, to demonstrate that this latent computationalism in the study of memory is problematic, and that it can and should be eliminated. Cognitive psychologists studying memory have encountered numerous data in recent decades that belie archival models. In cognitive neuroscience, establishing the neural basis of storage and retrieval processes has proven elusive. A number of revised models on offer in memory science, that have taken these issues into account, fail to sufficiently extricate the archival framework. Several impasses in memory science are products of these underlying computationalist assumptions. Wittgenstein and other philosophers offer a number of arguments against the need for, and the efficacy of, the storage and retrieval of traces in human remembering. A study of these arguments clarifies the ways that these computationalist assumptions are presently impeding the science of memory, and provides ways forward in removing them. We can and should characterize and model human memory without invoking the storage and retrieval of traces. A range of work in connectionism, dynamical systems theory, and recent philosophical accounts of memory demonstrate how the science of memory can proceed without these assumptions, toward non-archival models of remembering. (shrink)

We offer an ecological (Gibsonian) alternative to cognitive (im)penetrability. Whereas Pylyshyn explains cognitive (im)penetrability by focusing solely on computations carried out by the nervous system, according to the ecological approach the perceiver as a knowing agent influences the entire animal-environmental system: in the determination of what constitutes the environment (affordances), what constitutes information, what information is detected and, thus, what is perceived.

This paper (1) sketches a phenomenological analysis of visual mental imagery; (2) applies this analysis to the mental imagery debate in cognitive science; (3) briefly sketches a neurophenomenological approach to mental imagery; and (4) compares the results of this discussion with Dennett’s heterophenomenology.

This PhD thesis concerns introspective approaches to the study of the mind. Across three standalone papers, I examine the significance of introspective data and advise on appropriate kinds of training for the production of such data. An overview document first introduces major themes, methods and arguments of the thesis. Paper 1 then begins the argumentative work, interrogating the constraining function of introspection in cognitive science. Here, I evaluate “enactivist” claims about the significance of introspection, clarifying central enactivist suggestions to draw (...) out the broader importance of introspection in science and philosophy. Paper 2 then examines the proposed employment of Buddhist meditation practices in the production of rigorous introspective data. I defend such proposals against concerns that meditators yield ungeneralizable data, given the transformative character of these attention-training techniques. I argue that some meditation-trained transformations are actually epistemically-beneficial, undermining popular associations between transformation and “distortion”. Paper 3 then reviews difficulties involved in integrating meditative training into research. I emphasise the importance of specific contextual supports to meditation as critical ingredients of introspective proficiency, showing how difficulties replicating these threaten to limit the scope of meditation’s scientific benefits. I layout methodological responses to this that can maximise meditation’s positive impact going forwards. (shrink)

This paper defends a dynamic model of the way in which perception is integrated with action, a model I refer to as ‘the navigational account’. According to this account, employing vision and other forms of distance perception, a creature acquires information about its surroundings via the senses, information that enables it to select and navigate routes through its environment, so as to attain objects that satisfy its needs. This form of perceptually guided activity should be distinguished from other kinds of (...) semi-automatic responses to visual stimuli that do not necessarily involve conscious experiences. It essentially involves inner states, which involve both the awareness of phenomenal qualities, and also a representational component. The navigational account is compared here with the enactive approach to perception, which opposes the view that perceptual experiences are inner states. This paper argues that a full account of perception raises a number of different questions. One central explanatory project concerns questions about the kinds of processes that currently enable a creature to identify and respond appropriately to distant objects: the answer, it is argued, lies in acknowledging the role of conscious inner representations in guiding navigational behaviour through complex environments. The fact that perception and action are interdependent does not conflict with the claim that inner representational states comprise an essential stage in visual processing. (shrink)