This paper presents Integrated Information Theory of consciousness 3.0, which incorporates several advances over previous formulations. IIT starts from phenomenological axioms: information says that each experience is specific a sh it is what it is by how it differs from alternative experiences; integration says that it is unified a sh irreducible to non-interdependent components; exclusion says that it has unique borders and a particular spatio-temporal grain. These axioms are formalized into postulates that prescribe how physical mechanisms, such as neurons or (...) logic gates, must be configured to generate experience. The postulates are used to define intrinsic information as “differences that make a difference‘ within a system, and integrated information as information specified by a whole that cannot be reduced to that specified by its parts. By applying the postulates both at the level of individual mechanisms and at the level of systems of mechanisms, IIT arrives at an identity: an experience is a maximally irreducible conceptual structure, and the set of elements that generates it constitutes a complex. According to IIT, a MICS specifies the quality of an experience and integrated information Φ Max its quantity. From the theory follow several results, including: a system of mechanisms may condense into a major complex and non-overlapping minor complexes; the concepts that specify the quality of an experience are always about the complex itself and relate only indirectly to the external environment; anatomical connectivity influences complexes and associated MICS; a complex can generate a MICS even if its elements are inactive; simple systems can be minimally conscious; complicated systems can be unconscious; there can be true “zombies‘ a sh unconscious feed-forward systems that are functionally equivalent to conscious complexes. (shrink)

Assessing the scientific status of theories of consciousness is often a difficult task. In this paper, I explore the dialectic between the Integrated Information Theory, e1003588, 2014; Tononi et al. Nat Rev Neurosci, 17, 450-61, 2016) and a recently proposed criticism of that theory: the ‘unfolding argument’. I show that the phenomenology-first approach in consciousness research can lead to valid scientific theories of consciousness. I do this by highlighting the two reasons why the unfolding argument fails: first, phenomenology-first theories are (...) grounded, not circular. Second, falsificationism does not provide an adequate demarcation criterion in philosophy of science. I conclude that this specific debate has significance for how, in general, consciousness researchers test and criticize theories of consciousness, and how dismissing the phenomenology-first methodology in favour of a third person-based methodology means endorsing a position in philosophy of mind that has already been challenged. (shrink)

Do studies of perception without awareness and studies of perception without attention address a similar underlying concept of awareness? To answer this question, we compared qualitative differences in performance across variations in stimulus quality with qualitative differences in performance across variations in the direction of attention . The qualitative differences were based on three different phenomena: Stroop priming, false recognition, and exclusion failure. In all cases, variations in stimulus quality and variations in the direction of attention led to parallel findings. (...) These results suggest that perception with and without awareness and perception with and without attention are equivalent ways of describing the same underlying process distinction. (shrink)

The Stroop effect is composed of interference and facilitation effects. The facilitation is less stable and thus many times is referred to as a “fragile effect”. Here we suggest the facilitation effect is highly vulnerable to individual differences in control over the task conflict . We replicated previous findings of a significant correlation between stop-signal reaction time and Stroop interference, and also found a significant correlation between SSRT and the Stroop facilitation effect—participants with low inhibitory control had no facilitation effect (...) or even a reversed one. These results shed new light on the “fragile” facilitation effect and highlight the necessity of awareness of task conflict, especially in the Stroop task. (shrink)

The typical empirical approach to studying consciousness holds that we can only observe the neural correlates of experiences, not the experiences themselves. In this paper we argue, in contrast, that experiences are concrete physical phenomena that can causally interact with other phenomena, including observers. Hence, experiences can be observed and scientifically modelled. We propose that the epistemic gap between an experience and a scientific model of its neural mechanisms stems from the fact that the model is merely a theoretical construct (...) based on observations, and distinct from the concrete phenomenon it models, namely the experience itself. In this sense, there is a gap between any natural phenomenon and its scientific model. On this approach, a neuroscientific theory of the constitutive mechanisms of an experience is literally a model of the subjective experience itself. We argue that this metatheoretical framework provides a solid basis for the empirical study of consciousness. (shrink)

Most ?theories of consciousness? are based on vague speculations about the properties of conscious experience. We aim to provide a more solid basis for a science of consciousness. We argue that a theory of consciousness should provide an account of the very processes that allow us to acquire and use information about our own mental states ? the processes underlying introspection. This can be achieved through the construction of information processing models that can account for ?Type-C? processes. Type-C processes can (...) be specified experimentally by identifying paradigms in which awareness of the stimulus is necessary for an intentional action. The Shallice (1988b) framework is put forward as providing an initial account of Type-C processes, which can relate perceptual consciousness to consciously performed actions. Further, we suggest that this framework may be refined through the investigation of the functions of prefrontal cortex. The formulation of our approach requires us to consider fundamental conceptual and methodological issues associated with consciousness. The most significant of these issues concerns the scientific use of introspective evidence. We outline and justify a conservative methodological approach to the use of introspective evidence, with attention to the difficulties historically associated with its use in psychology. (shrink)

In the ongoing research of the functions of consciousness, special emphasis has been put on integration of information: the ability to combine different signals into a coherent, unified one. Several theories of consciousness hold that this ability depends on – or at least goes hand in hand with – conscious processing. Yet some empirical findings have suggested otherwise, claiming that integration of information could take place even without awareness. Trying to reconcile this apparent contradiction, the “windows of integration” hypothesis claims (...) that conscious access enables signal processing over large integration windows. The hypothesis applies to integration windows defined either temporally, spatially, or semantically. In this review, we explain the hypothesis and re-examine it in light of new studies published since it was suggested. In line with the hypothesis, these studies provide compelling evidence for unconscious integration, but also demonstrate its limits with respect to time, space, and semantic distance. The review further highlights open questions that still need to be pursued to demonstrate the applicability of the WOI hypothesis as a guiding principle for understanding the depth and scope of unconscious processes. (shrink)

Recent research suggests that processing of irrelevant information can be modulated in a rapid online fashion by contextual information in the task environment depending on the usefulness of that information in different contexts. Congruency effects evoked by irrelevant stimulus attributes are smaller in contexts with high proportions of incongruent trials and larger in contexts with high proportions of congruent trials . The present study investigates these context-adaptation effects in a masked-priming paradigm. Context-specific adaptation effects transfer to stimulus identities that are (...) equiprobale in all contexts – an observation that renders explanations in terms of event-learning processes unlikely. Yet, context-specific effects vanished when the irrelevant information remained unconscious. The results suggest that context-specific adaptation of congruency effects reflect cognitive control operations that alter the processing of irrelevant information depending on the experienced utility of that information for action control. (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)

This introductory chapter attempts to clarify the philosophical, empirical, and theoretical bases on which a cognitive neuroscience approach to consciousness can be founded. We isolate three major empirical observations that any theory of consciousness should incorporate, namely (1) a considerable amount of processing is possible without consciousness, (2) attention is a prerequisite of consciousness, and (3) consciousness is required for some specific cognitive tasks, including those that require durable information maintenance, novel combinations of operations, or the spontaneous generation of intentional (...) behavior. We then propose a theoretical framework that synthesizes those facts: the hypothesis of a global neuronal workspace. This framework postulates that, at any given time, many modular cerebral networks are active in parallel and process information in an unconscious manner. An information becomes conscious, however, if the neural population that represents it is mobilized by top-down attentional amplification into a brain-scale state of coherent activity that involves many neurons distributed throughout the brain. The long-distance connectivity of these `workspace neurons' can, when they are active for a minimal duration, make the information available to a variety of processes including perceptual categorization, long-term memorization, evaluation, and intentional action. We postulate that this global availability of information through the workspace is what we subjectively experience as a conscious state. A complete theory of consciousness should explain why some cognitive and cerebral representations can be permanently or temporarily inaccessible to consciousness, what is the range of possible conscious contents, how they map onto specific cerebral circuits, and whether a generic neuronal mechanism underlies all of them. We confront the workspace model with those issues and identify novel experimental predictions. Neurophysiological, anatomical, and brain-imaging data strongly argue for a major role of prefrontal cortex, anterior cingulate, and the areas that connect to them, in creating the postulated brain-scale workspace. (shrink)

This paper provides some responses to Tom Polger and Larry Shapiro’s The Multiple Realization Book (2016). I first provide a description of the authors’ framework for thinking about multiple realization and the conditions they claim this involves. I explain what I think they get right and what they get wrong with this framework. After this, I then consider a few examples of multiple realization they discuss and the interpretations they offer. While I am sympathetic to several things they say about (...) multiple realization, I also think there are some questions that have yet to be answered. (shrink)

In this paper we provide a philosophical analysis of the Hard Problem of consciousness and the implications of conceivability scenarios for current neuroscientific research. In particular, we focus on one of the most prominent neuroscientific theories of consciousness, integrated information theory (IIT). After a brief introduction on IIT, we present Chalmers’ original formulation and propose our own layered view of the hard problem, showing how 2 separate issues can be distinguished. More specifically, we argue that it’s possible to disentangle a (...) core problem of consciousness from a layered hard problem, the latter being essentially connected to Chalmers’ conceivability argument. We then assess the relation between the Hard Problem and IIT, showing how the theory resists conceivability scenarios, and how it is equipped to face up to the hard problem in its broadest acceptation. (shrink)

The question of whether conscious experience is restricted by cognitive access and exhausted by report, or whether it overflows it—comprising more information than can be reported—is hotly debated. Recently, we provided evidence in favor of Overflow, showing that observers discriminated the color‐diversity (CD) of letters in an array, while their working‐memory and attention were dedicated to encoding and reporting a set of cued letters. An alternative interpretation is that CD‐discriminations do not entail conscious experience of the underlying colors. Here we (...) argue, based on conceptual considerations and consistency with neuroscience and phenomenology, in favor of the Overflow interpretation. (shrink)

Let psychologism be the doctrine that whether behavior is intelligent behavior depends on the character of the internal information processing that produces it. More specifically, I mean psychologism to involve the doctrine that two systems could have actual and potential behavior _typical_ of familiar intelligent beings, that the two systems could be exactly alike in their actual and potential behavior, and in their behavioral dispositions and capacities and counterfactual behavioral properties (i.e., what behaviors, behavioral dispositions, and behavioral capacities they would (...) have exhibited had their stimuli differed)--the two systems could be alike in all these ways, yet there could be a difference in the information processing that mediates their stimuli and responses that determines that one is not at all intelligent while the other is fully intelligent. (shrink)

One of the most important issues concerning the foundations ofconscious perception centerson thequestion of whether perceptual consciousness is rich or sparse. The overflow argument uses a form of ‘iconic memory’ toarguethatperceptual consciousnessisricher (i.e.,has a higher capacity) than cognitive access: when observing a complex scene we are conscious of more than we can report or think about. Recently, the overflow argumenthas been challenged both empirically and conceptually. This paper reviews the controversy, arguing that proponents of sparse perception are committed to the (...) postulation of (i) a peculiar kind of generic conscious representation that has no independent rationale and (ii) an unmotivated form of unconscious representation that in some cases conflicts with what we know about unconscious representation. (shrink)

Integrated Information Theory (IIT) of Consciousness is becoming an increasingly popular neuroscientific account of phenomenal experience. IIT claims that consciousness is integrated information in a system. I set this theory against the hard problem of consciousness (Chalmers, 1996, 1995) as the goal for a theory of consciousness to meet. In this essay I look to examine and ultimately critique IIT’s use of the notion of information to base a theory of consciousness. I argue that the notion of information in IIT (...) is a purely structural-dynamical notion, and so falls afoul of the structure and dynamics argument (Chalmers, 2003). I bolster these claims by appeal to the explanatory gap argument and show how IIT succumbs to this argument as well. For these reasons, I call into doubt IIT’s ability to answer the hard problem of consciousness. Although this paper argues against the notion of information in IIT, in a broader context the criticisms which I raise here can be brought against any theory that attempts to explain consciousness as an information-theoretic phenomenon. (shrink)

Uncovering the neural basis of consciousness is a major challenge to neuroscience. In this Perspective, Tononi and colleagues describe the integrated information theory of consciousness and how it might be used to answer outstanding questions about the nature of consciousness.

According to the integrated information theory of consciousness, consciousness is a fundamental observer-independent property of physical systems, and the measure Phi of integrated information is identical to the quantity or level of consciousness. For this to be plausible, there should be no alternative formulae for Phi consistent with the axioms of IIT, and there should not be cases of F being ill-defined. This article presents three ways in which Phi, in its current formulation, fails to meet these standards, and discusses (...) how this problem might be addressed. (shrink)