This review addresses the role of early sensory areas in the awareness of tactile information in humans. The results of recent studies dealing with this important topic are critically discussed: In particular, we report on evidence from neuropsychology, neurophysiology, neuroimaging, and behavioral experiments that have highlighted the crucial role played by the primary somatosensory cortex in mediating our awareness of tactile information. Phenomena, such as tactile hallucinations, tactile illusions, the perception of supernumerary limbs, and synaesthesia are also discussed. The research (...) reviewed here clearly shows that the activation of SI is necessary, but not sufficient, for the awareness of touch. On the basis of the evidence outlined here, we propose a neurocognitive model that provides a conceptual framework in which to interpret the results of the literature regarding tactile consciousness. (shrink)

It appears that consciousness science is progressing soundly, in particular in its search for the neural correlates of consciousness. There are two main approaches to this search, one is content-based (focusing on the contrast between conscious perception of, e.g., faces vs. houses), the other is state-based (focusing on overall conscious states, e.g., the contrast between dreamless sleep vs. the awake state). Methodological and conceptual considerations of a number of concrete studies show that both approaches are problematic: the content-based approach seems (...) to set aside crucial aspects of consciousness; and the state-based approach seems over-inclusive in a way that is hard to rectify without losing sight of the crucial conscious-unconscious contrast. Consequently, the search for the neural correlates of consciousness is in need of new experimental paradigms. (shrink)

Intuitively, there is a close link between moral status and phenomenal consciousness. Taking the link seriously can serve as the basis of a proposal that appears to have a surprising number of theoretical benefits. This proposal is the moral option, according to which moral status is partly determinative of phenomenal consciousness, and phenomenal consciousness is sufficient for possession of a moral property I refer to as “moral status.” I argue for this view on the basis of its ability to shed (...) light on the distribution problem of determining which systems are phenomenally conscious. I explicate it by drawing on a theory of attributions of phenomenal consciousness, and considering its relationship to positions on the metaphysics of consciousness. I defend it against a series of objections, including three based on previous theories of the link between phenomenal consciousness and moral status. The moral option should, in my view, be a serious contender among theories of phenomenal consciousness. (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)

An important distinction lies between consciousness attributed to creatures, or subjects, (creature consciousness) and consciousness attributed to mental states (state consciousness). Most contemporary theories of consciousness aim at explaining what makes a mental state conscious, paying scant attention to the problem of creature consciousness. This attitude relies on a deeper, and generally overlooked, assumption that once an explanation of state consciousness is provided, one has also explained all the relevant features of creature consciousness. I call this the priority of state (...) consciousness thesis (PSC). In this paper, I want to explore how the renewed centrality bestowed to phenomenology in contemporary discussions on consciousness challenges PSC and, consequently, the standard way of framing the problem of consciousness. More precisely, I examine PSC in light of a view about the structure of phenomenal character that is paradigmatic of the approach above. This is subjectivism about phenomenal character (SUBJ), according to which a mental state is conscious when it acquires the property of for-me-ness. I argue that PSC and SUBJ are incompatible because the latter implies that creature consciousness is explanatorily prior to state consciousness. Consequently, if SUBJ is true, then PSC is false, and what constitutes the problem of consciousness is primarily a problem of explaining (a kind of) creature consciousness. I conclude by defending my claim from a pair of possible objections and drawing some implications for the discussion of for-me-ness and the debate on the explanation of consciousness. (shrink)

There are many theories of the functions of consciousness. How these theories relate to each other, how we should assess them, and whether any integration of them is possible are all issues that remain unclear. To contribute to a solution, this paper offers a conceptual framework to clarify the theories of the functions of consciousness. This framework consists of three dimensions: (i) target, (ii) explanatory order, and (iii) necessity/sufficiency. The first dimension, target, clarifies each theory in terms of the kind (...) of consciousness it targets. The second dimension, explanatory order, clarifies each theory in terms of how it conceives of the explanatory relation between consciousness and function. The third dimension, necessity/sufficiency, clarifies each theory in terms of the necessity/sufficiency relation posited between consciousness and function. We demonstrate the usefulness of this framework by applying it to some existing scientific and philosophical theories of the functions of consciousness. (shrink)

The accurate measurement of the level of consciousness of a creature remains a major scientific challenge, nevertheless a number of new accounts that attempt to address this problem have been proposed recently. In this paper we analyze the principles of these new measures of consciousness along with other classical approaches focusing on their applicability to Machine Consciousness (MC). Furthermore, we propose a set of requirements of what we think a suitable measure for MC should be, discussing the associated theoretical and (...) practical issues. Using the proposed requirements as a framework for the design of an integrative measure of consciousness, we explore the possibility of designing such a measure in the context of current state of the art in consciousness studies. (shrink)