An important approach to understand how the brain gives rise to consciousness is to probe the depth of unconscious processing, thus to define the key features that cause conscious awareness. Here, we investigate the possibility for subliminal stimuli to shape the context for unconscious processing. Context effects have generally been assumed to require consciousness. In the present experiment, unconscious context processing was investigated by looking at the impact of the context on the response activation elicited by a subliminal prime. We (...) compared the effects of the same subliminal prime on target processing when the prime was embedded in different unconscious contexts. Results showed that the same prime can evoke opposite responses depending on the unconscious context in which it is presented. Taken together, the results of this study show that context effects can be unconscious. (shrink)

In the past decades, affective science has overwhelmingly demonstrated the unique properties of affective information to bias our attention, memory, and decisions. At the same time, accumulating evidence suggests that neutral and affective representations rely on the same working memory substrates for the selection and computation of information and that they are therefore restricted by the same capacity limitations that these substrates impose. Here, we integrate these insights into a working memory model of affective processing (WMAP). Drawing on competitive access (...) models of working memory, we discuss its role in the various stages of affective processing, from attentional selection to maintenance and memory storage, and resulting feelings and actions. We end our overview with some open questions and future directions. (shrink)

An alternative model of the relation between consciousness and self-consciousness is proposed. The model combines a non-standard version of the higher-order theory of consciousness with the global neuronal workspace theory and argues that implicit higher-order self-awareness is a pervasive feature of the globally integrative states formed in the global workspace.

At the very heart of the mind-body problem is the question of the nature of consciousness. It is consciousness, and in particular _phenomenal_ consciousness, that makes the mind-body relation so deeply perplexing. Many philosophers hold that no defi nition of phenomenal consciousness is possible: any such putative defi nition would automatically use the concept of phenomenal consciousness and thus render the defi nition circular. The usual view is that the concept of phenomenal consciousness is one that must be explained by (...) means of specifi c examples and associated comments. (shrink)

Imaginings are often characterized in terms of vividness. However, there is little agreement in the philosophical literature as to what it amounts to and how to even investigate it. In this paper, we propose a natural kind methodology to study vividness and suggest treating it as a homeostatic property cluster with an underlying nature that explains the correlation of properties in that cluster. This approach relies on the empirical research on the vividness of mental imagery and contrasts with those accounts (...) that treat vividness as an explanatory primitive and with those that attempt to provide a definition. We apply the natural kind methodology to make several substantive claims about the vividness of mental imagery. First, we will argue that it forms a homeostatic property cluster, in that it is reliably correlated with, but not defined by, some properties, such as the level of detail, clarity, perception-likeness and intensity. In arguing for this claim, we also show how the cluster can be modified in the light of empirical research by complementing it with a correlation between vividness and familiarity. Second, we will argue that these correlations can be explained by an underlying property at the architectural level; i.e., the availability of stored sensory information for the elaboration of a mental image. (shrink)

Processes comparable in important respects to those underlying human conscious and non-conscious processing can be identified in a range of species and it is argued that these reflect evolutionary precursors of the human processes. A distinction is drawn between two types of processing: stimulus-based and higher-order. For ‘higher-order,’ in humans the operations of processing are themselves associated with conscious awareness. Conscious awareness sets the context for stimulus-based processing and its end-point is accessible to conscious awareness. However, the mechanics of the (...) translation between stimulus and response proceeds without conscious control. The paper argues that higher-order processing is an evolutionary addition to stimulus-based processing. The model’s value is shown for gaining insight into a range of phenomena and their link with consciousness. These include brain damage, learning, memory, development, vision, emotion, motor control, reasoning, the voluntary versus involuntary debate, and mental disorder. (shrink)

The Ouroboros Model features a biologically inspired cognitive architecture. At its core lies a self-referential recursive process with alternating phases of data acquisition and evaluation. Memory entries are organized in schemata. The activation at a time of part of a schema biases the whole structure and, in particular, missing features, thus triggering expectations. An iterative recursive monitor process termed "consumption analysis" is then checking how well such expectations fit with successive activations. Mismatches between anticipations based on previous experience and actual (...) current data are highlighted and used for controlling the allocation of attention. In case no directly fitting filler for an open slot is found, activation spreads more widely and includes data relating to the actor, and Higher-Order Personality Activation, HOPA, ensues. It is briefly outlined how the Ouroboros Model produces many diverse characteristics and thus addresses established criteria for consciousness. Coarse-grained relationships to selected previous conceptualizations of consciousness and a sketch of how the Ouroboros Model could shed light on current research themes in artificial general intelligence and consciousness conclude this paper. (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)

For consciousness to exist, an entity must have prerequisite characteristics and attributes to give rise to it. We explore these “building blocks” of consciousness in detail in this paper, which range from perceptive to computational to meta-representational characteristics of an entity’s cognitive architecture. We show how each cognitive attribute is strictly necessary for the emergence of consciousness, and how the building blocks may be used for any entity to be classified as being conscious. The list of building blocks is not (...) limited to human or organic consciousness and may be used to classify artificial and organisational conscious entities. We further explore a list of attributes that seem intuitively necessary for consciousness, but on further investigation, are neither required nor sufficient. The building blocks do not represent a theory of consciousness but rather a meta-theory on the emergence and classification of consciousness. (shrink)

Studies on so-called Change Blindness and Inattentional Blindness have been taken to establish the claim that conscious perception of a stimulus requires the attentional processing of that stimulus. One might contend, against this claim, that the evidence only shows attention to be necessary for the subject to have access to the contents of conscious perception and not for conscious perception itself. This “Methodological Argument” is gaining ground among philosophers who work on attention and consciousness, such as Christopher Mole. I find (...) that, without the supporting evidence of inaccessible consciousness, this argument collapses into an indefensible form of inductive parsimony. The Methodological Argument is thus shown to be unsuccessful when used against the claim that attention is required for conscious perception, though I suggest that it may be successful against the more ambitious claim that attention is necessary for all conscious experience. (shrink)

The purpose of the present article is to explore the relationship between consciousness and understanding. To do so, I first briefly review recent work on the nature of both understanding and consciousness within philosophy and psychology. Building off of this work, I then defend the thesis that if one is conscious of a given content then one also understands that content. I argue that this conclusion can be drawn from the fact that understanding is associated with rational intention formation and (...) the fact that conscious access appears to involve the selective routing/broadcasting of representational content to neural systems that integrate information in order to select cognitive/behavioral intentions in conjunction with goals. Based on these premises I illustrate how a disruption to the rationality of a representation’s influence on intention formation would also remove any evidence that a person was conscious of the content of that representation... (shrink)

Three experiments investigated the relationship between subjective experience and attentional lapses during sustained attention. These experiments employed two measures of subjective experience to examine how differences in awareness correspond to variations in both task performance and psycho-physiological measures . This series of experiments examine these phenomena during the Sustained Attention to Response Task . The results suggest we can dissociate between two components of subjective experience during sustained attention: task unrelated thought which corresponds to an absent minded disengagement from the (...) task and a pre-occupation with one's task performance that seems to be best conceptualised as a strategic attempt to deploy attentional resources in response to a perception of environmental demands which exceed ones ability to perform the task. The implications of these findings for our understanding of how awareness is maintained on task relevant material during periods of sustained attention are discussed. (shrink)

Three experiments investigated the relationship between subjective experience and attentional lapses during sustained attention. These experiments employed two measures of subjective experience to examine how differences in awareness correspond to variations in both task performance and psycho-physiological measures . This series of experiments examine these phenomena during the Sustained Attention to Response Task . The results suggest we can dissociate between two components of subjective experience during sustained attention: task unrelated thought which corresponds to an absent minded disengagement from the (...) task and a pre-occupation with one's task performance that seems to be best conceptualised as a strategic attempt to deploy attentional resources in response to a perception of environmental demands which exceed ones ability to perform the task. The implications of these findings for our understanding of how awareness is maintained on task relevant material during periods of sustained attention are discussed. (shrink)

Consciousness researchers are interested in distinguishing between mental activity that occurs with and without awareness . The inattentional blindness paradigm is an excellent tool for this question because it permits the independent manipulation of processing time and awareness. In the present study, we show that implicit texture segregation can occur during inattentional blindness, provided that the texture is exposed for a sufficient duration. In contrast, a Simon effect does not occur during inattentional blindness, even with similar exposure duration of the (...) critical stimulus. This reveals a dissociation between processing time and awareness, consistent with the possibility of separate processing streams for explicit and implicit visual perception. (shrink)

This is the first of two papers in which we propose an evolutionary route for the transition from sensory processing to unlimited experiencing, or basic consciousness. We argue that although an evolutionary analysis does not provide a formal definition and set of sufficient conditions for consciousness, it can identify crucial factors and suggest what evolutionary changes enabled the transition. We believe that the raw material from which feelings were molded by natural selection was a global sensory state that we call (...) overall sensation, which is a by-product of the incessant activity of the highly interconnected nervous systems that characterize all neural animals. We argue that global sensory states generated limited experiencing once they became coupled to the simplest kinds of nervous-system-mediated learning, a coupling that occurred in the most ancient taxa of neural animals, which were similar to present-day cnidarians and ctenophores. In such animals, limited experiencing involves a small number of persistent global sensory states. These sensory states, however, do not have a function and do not act as motivational states. As we argue in the next paper, with the evolution of associative learning they evolved into systems that gave animals basic consciousness. (shrink)

Most scientific theories of consciousness are challenging to apply outside the human case insofar as non‐human systems (both biological and artificial) are unlikely to implement human architecture precisely, an issue I call the specificity problem. After providing some background on the theories of consciousness debate, I survey the prospects of four approaches to this problem. I then consider a fifth solution, namely the theory‐light approach proposed by Jonathan Birch. I defend a modified version of this that I term the modest (...) theoretical approach, arguing that it may provide insights into challenging cases that would otherwise be intractable. (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)

The question of whether non-human animals are conscious is of fundamental importance. There are already good reasons to think that many are, based on evolutionary continuity and other considerations. However, the hypothesis is notoriously resistant to direct empirical test. Numerous studies have shown behaviour in animals analogous to consciously-produced human behaviour. Fewer probe whether the same mechanisms are in use. One promising line of evidence about consciousness in other animals derives from experiments on metamemory. A study by Hampton (Proc Natl (...) Acad Sci USA 98(9):5359–5362, 2001 ) suggests that at least one rhesus macaque can use metamemory to predict whether it would itself succeed on a delayed matching-to-sample task. Since it is not plausible that mere meta-representation requires consciousness, Hampton’s study invites an important question: what kind of metamemory is good evidence for consciousness? This paper argues that if it were found that an animal had a memory trace which allowed it to use information about a past perceptual stimulus to inform a range of different behaviours, that would indeed be good evidence that the animal was conscious. That functional characterisation can be tested by investigating whether successful performance on one metamemory task transfers to a range of new tasks. The paper goes on to argue that thinking about animal consciousness in this way helps in formulating a more precise functional characterisation of the mechanisms of conscious awareness. (shrink)

In this interesting paper, Lavazza and Massimini draw attention to a subset of the ethical issues surrounding the development and potential uses of cerebral organoids. This subset concerns the possibility that cerebral organoids may one day develop phenomenal consciousness, and thereby qualify as conscious subjects—that there may one day be something it is like to be an advanced cerebral organoid. This possibility may feel outlandish. But as Lavazza and Massimini demonstrate, the science of organoids is moving fast, and I agree (...) that the ethical issues now deserve careful scrutiny. The ethical issues are not entirely separate from epistemological issues concerning how certain we could ever be that an organoid is conscious or that regarding any conscious state or process, an organoid is capable of tokening that state or undergoing that process. Lavazza and Massimini’s approach is theory-based—they claim that ‘we need a general theory of consciousness that attempts to explain what experience is and what type of physical systems can have it’. I am not convinced, however, that a theory of consciousness is what we need. Nor am I convinced that detecting the presence of consciousness is the most important moral issue. Let me say a word regarding theories of consciousness first. In general, to the extent that pervasive disagreement characterises expert discussion of some phenomenon P, one should modify one’s credence downward regarding any theory of the nature of P. In my view, this is the case regarding expert discussion of consciousness. Although most philosophers are confident that consciousness is an entirely physical phenomenon, a …. (shrink)

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

Prior to the initiation of spontaneous movement, evoked potentials can be seen to precede awareness of the impending movement by several hundreds of milliseconds, meaning that this recorded neural activity is the result of unconscious processing. This study investigates the neural representations of impending movement with and without awareness. Specifically, the relationship between awareness and ‘idling’ cortical oscillations in the beta range was assessed. It was found that, in situations where there was awareness of the impending movement, pre-movement evoked potentials (...) were associated with a decrease in beta range oscillations. In contrast, when awareness of the impending movement was not present, the onset of the pre-movement potential was associated with tonic levels of beta range oscillations. A model is considered where by distributed neural activity remains outside of conscious awareness through the persistence of tonic slow wave cortical oscillations. (shrink)

Alleged self-evidence aside, conceivability arguments are one of the main reasons in favor of the claim that there is a Hard Problem. These arguments depend on the appealing Kripkean intuition that there is no difference between appearances and reality in the case of consciousness. I will argue that this intuition rests on overlooking a distinction between cognitive access and consciousness, which has received recently important empirical support. I will show that there are good reasons to believe that the intuition is (...) misguided—at least on the reading that the conceivability arguments require—and hence that the arguments are unsupported. This, in turn, alleviates the Hard Problem but leaves us with what I think is a not easy problem. (shrink)

Cognitive theories claim, whereas non-cognitive theories deny, that cognitive access is constitutive of phenomenology. Evidence in favor of non-cognitive theories has recently been collected by Block and is based on the high capacity of participants in partial-report experiments compared to the capacity of the working memory. In reply, defenders of cognitive theories have searched for alternative interpretations of such results that make visual awareness compatible with the capacity of the working memory; and so the conclusions of such experiments remain controversial. (...) Instead of entering the debate between alternative interpretations of partial-report experiments, this paper offers an alternative line of research that could settle the discussion between cognitive and non-cognitive theories of consciousness. Here I relate the neural correlates of cognitive access to empirical research into the neurophysiology of dreams; cognitive access seems to depend on the activity of the dorsolateral prefrontal cortex. However, that area is strongly deactivated during sleep; a period when we entertain conscious experiences: dreams. This approach also avoids the classic objection that consciousness should be inextricably tied to reportability or it would fall outside the realm of science. (shrink)

The non-transitivity of the relation looks the same as has been used to argue that the relation has the same phenomenal character as is non-transitive—a result that jeopardizes certain theories of consciousness. In this paper, I argue against this conclusion while granting the premise by dissociating lookings and phenomenology; an idea that some might find counter-intuitive. However, such an intuition is left unsupported once phenomenology and cognitive access are distinguished from each other; a distinction that is conceptually and empirically grounded.

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)

The attempt to model the structure of consciousness in split-brain subjects is ongoing. This paper concerns the recently proposed ?switch model? of split-brain consciousness, according to which a split-brain subject possesses only a single stream of consciousness, unified at and across time, that shifts from one hemisphere to the other from moment to moment. The paper argues that while the central explanatory element of the switch model may account for some aspects of split-brain consciousness, the best general picture of split-brain (...) consciousness is still offered by some version of the ?conscious duality model.? (shrink)

This article re-examines Ned Block‘s ( 1997 , 2007 ) conceptual distinction between phenomenal consciousness and access consciousness. His argument that we can have phenomenally conscious representations without being able to cognitively access them is criticized as not being supported by evidence. Instead, an alternative interpretation of the relevant empirical data is offered which leaves the link between phenomenology and accessibility intact. Moreover, it is shown that Block’s claim that phenomenology and accessibility have different neural substrates is highly problematic in (...) light of empirical evidence. Finally, his claim that there can be phenomenology without cognitive accessibility is at odds with his endorsement of the 'same-order-theory' of consciousness. (shrink)

This paper examines the possibility of finding evidence that phenomenal consciousness is independent of access. The suggestion reviewed is that we should look for isomorphisms between phenomenal and neural activation spaces. It is argued that the fact that phenomenal spaces are mapped via verbal report is no problem for this methodology. The fact that activation and phenomenal space are mapped via different means does not mean that they cannot be identified. The paper finishes by examining how data addressing this theoretical (...) question could be obtained. (shrink)

If you’re a materialist, you probably think that rabbits are conscious. And you ought to think that. After all, rabbits are a lot like us, biologically and neurophysiologically. If you’re a materialist, you probably also think that conscious experience would be present in a wide range of naturally-evolved alien beings behaviorally very similar to us even if they are physiologically very different. And you ought to think that. After all, to deny it seems insupportable Earthly chauvinism. But a materialist who (...) accepts consciousness in weirdly formed aliens ought also to accept consciousness in spatially distributed group entities. If she then also accepts rabbit consciousness, she ought to accept the possibility of consciousness even in rather dumb group entities. Finally, the United States would seem to be a rather dumb group entity of the relevant sort. If we set aside our morphological prejudices against spatially distributed group entities, we can see that the United States has all the types of properties that materialists tend to regard as characteristic of conscious beings. (shrink)

Recent accounts on the global workspace theory suggest that consciousness involves transient formations of functional connections in thalamo-cortico-cortical networks. The level of connectivity in these networks is argued to determine the state of consciousness. Emotions are suggested to play a role in shaping consciousness, but their involvement in the global workspace theory remains elusive. In the present study, the role of emotion in the neural workspace theory of consciousness was scrutinized by investigating, whether unconscious and conscious display of emotional compared (...) to neutral facial expressions would differentially modulate EEG coherence. EEG coherence was measured by means of computing an average EEG coherence value between the frontal, parietal, and midline scalp sites. Objective awareness checks evidenced that conscious identification of the masked facial expressions was precluded. Analyses revealed reductions in EEG coherence in the lower frequency range for the masked as compared to unmasked neutral facial expressions. Crucially, a decline in EEG coherence was not observed for the emotional facial expressions. In other words, the level of EEG coherence did apparently vary as a function of awareness, but not when emotion was involved. The current finding suggests that EEG coherence is modulated by unconscious emotional processes, which extends common views on the global workspace architecture of consciousness. (shrink)

Recent accounts on the global workspace theory suggest that consciousness involves transient formations of functional connections in thalamo-cortico-cortical networks. The level of connectivity in these networks is argued to determine the state of consciousness. Emotions are suggested to play a role in shaping consciousness, but their involvement in the global workspace theory remains elusive. In the present study, the role of emotion in the neural workspace theory of consciousness was scrutinized by investigating, whether unconscious and conscious display of emotional compared (...) to neutral facial expressions would differentially modulate EEG coherence. EEG coherence was measured by means of computing an average EEG coherence value between the frontal, parietal, and midline scalp sites. Objective awareness checks evidenced that conscious identification of the masked facial expressions was precluded. Analyses revealed reductions in EEG coherence in the lower frequency range for the masked as compared to unmasked neutral facial expressions. Crucially, a decline in EEG coherence was not observed for the emotional facial expressions. In other words, the level of EEG coherence did apparently vary as a function of awareness, but not when emotion was involved. The current finding suggests that EEG coherence is modulated by unconscious emotional processes, which extends common views on the global workspace architecture of consciousness. (shrink)