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Block [Block, N. (2005). Two neural correlates of consciousness. Trends in Cognitive Science, 9, 46-52] and Snodgrass (2006) claim that a signal detection theory (SDT) analysis of qualitative difference paradigms, in particular the exclusion failure paradigm, reveals cases of phenomenal consciousness without access consciousness. This claim is unwarranted on several grounds. First, partial cognitive access rather than a total lack of cognitive access can account for exclusion failure results. Second, Snodgrass's Objective Threshold/Strategic (OT/S) model of perception relies on a problematic 'enable' approach to perception that denies the possibility of intentional control of unconscious perception and any effect of following different task instructions on the presence/absence of phenomenal consciousness. Many of Block's purported examples of phenomenal consciousness without cognitive access also rely on this problematic approach. Third, qualitative difference paradigms may index only a subset of access consciousness. Thus, qualitative difference paradigms like exclusion failure cannot be used to isolate phenomenal consciousness, any attempt to do so still faces serious methodological problems.

This paper argues for a position of 'dark pessimism' towards introspective reports playing a strong justificatory role in consciousness science, based on the application of frameworks and concepts of measurement. I first show that treating introspective reports as measurements fits well within current discussions of the reliability of introspection, and argue that introspective reports must satisfy at least a minimal definition of measurement in order to play a justificatory role in consciousness science. I then show how treating introspective reports as measurements makes it possible to identify the foundational methodological problems that underlie much of the current philosophical and scientific debate about the status of introspective evidence in studying consciousness. I argue that these problems prevent introspective reports from playing a strong justificatory role and resolving long-standing debates in consciousness science, both in contemporary work and in the future. [ABSTRACT FROM AUTHOR]

Identifying which nonhuman animal species are capable of feeling pain is important both for understanding pain mechanisms more generally and for informing animal welfare regulations, particularly in genera that are not yet widely protected. A common way to try to provide evidence of pain experiences is through behavioral indicators. In this paper I use a very simple interventionist approach to experimentation, and the contrast case provided by C. elegans , to argue that behavioral indicators commonly used for identifying pain in nonhuman animals are much less robust than typically presented. Indeed, I argue that many behavioral indicators of pain are invalid as they are currently described. More positively, this analysis makes it possible to identify what valid criteria might look like, and where relevant, to identify existing evidence related to them. Based on this I propose that the best way to make progress on questions around animal pain is to clearly ally them with questions about animal consciousness more generally, and to productively use conceptual and empirical work in both areas to develop more theoretically defensible behavioral indicators. [ABSTRACT FROM AUTHOR]

It has been theorized that cortical feed-forward and recurrent neural activity support unconscious and conscious cognitive processes, respectively. Here we causally tested this proposition by applying event-related transcranial magnetic stimulation (TMS) at early and late times relative to visual stimuli, together with a pulse designed to suppress conscious detection. Consistent with pre-registered hypotheses, early TMS affected residual, reportedly 'unseen' capacity. However, conscious perception also appeared critically dependent upon feed-forward processing to a greater extent than the later recurrent phase. Additional exploratory analyses suggested that these early effects dissociated from top-down criterion measures, which were most affected by later TMS. These findings are inconsistent with a simple dichotomy where feed-forward and recurrent processes correspond to unconscious and conscious mechanisms. Instead, different components of awareness may correspond to different phases of cortical dynamics in which initial processing is broadly perceptual whereas later recurrent processing might relate to decision to report. [ABSTRACT FROM AUTHOR]

Abstract: Snodgrass et al.’s (2009) commentary makes explicit one of the major problems in consciousness research; that there seem to be just as many definitions of basic terms are there are people in the field. Although Snodgrass et al.’s position appears at odds with the views expressed in Irvine (2009), many of their arguments are actually consistent with the proposed views, or else fail to engage with them as a consequence of the shifting goal posts of what basic terms mean. [Copyright &y& Elsevier]

Consciousness is now a hot topic in both philosophy and the cognitive sciences, yet there is much controversy over how to measure it. First, it is not clear whether biased subjective reports should be taken as adequate for measuring consciousness, or if more objective measures are required. Ways to benefit from the advantages of both these measures in the form of 'Type 2' metacognitive measures are under development, but face criticism. Research into neurophysiological measures of consciousness is potentially very valuable, but often hindered by its dependence on behavioural measures that are themselves controversial. Newer informational measures are theoretically interesting, but as yet not easily applicable, while other measures of consciousness are designed for application in clinical cases (e.g. vegetative state). Although much optimism accompanies research into measures of consciousness, the controversies and methodological problems reviewed here suggest that making progress in this area may be more difficult than is often acknowledged. [ABSTRACT FROM AUTHOR]