When consciousness is examined using subjective ratings, the extent to which processing is conscious or unconscious is often estimated by calculating task performance at the subjective threshold or by calculating the correlation between accuracy and awareness. However, both these methods have certain limitations. In the present article, we propose describing task accuracy and awareness as functions of stimulus intensity as suggested by Koch and Preuschoff . The estimated lag between the curves describes how much stimulus intensity must increase for awareness (...) to change proportionally as much as accuracy and the slopes of the curves are used to assess how fast accuracy and awareness increases and whether awareness is dichotomous. The method is successfully employed to assess consciousness characteristics on data from four different awareness scales. (shrink)

This paper uses the Process Dissociation Procedure to explore whether people can acquire unconscious knowledge in the serial reaction time task [Destrebecqz, A., & Cleeremans, A. . Can sequence learning be implicit? New evidence with the Process Dissociation Procedure. Psychonomic Bulletin & Review, 8, 343–350; Wilkinson, L., & Shanks, D. R. . Intentional control and implicit sequence learning. Journal of Experimental Psychology: Learning, Memory, and Cognition, 30, 354–369]. Experiment 1 showed that people generated legal sequences above baseline levels under exclusion (...) instructions. Reward moved exclusion performance towards baseline, indicating that the extent of motivation in the test phase influenced the expression of unconscious knowledge. Experiments 2 and 3 revealed that even with reward, adding noise to the sequences or shortening training led to above-baseline exclusion performance, suggesting that task difficulty and the amount of training also affected the expression of unconscious knowledge. The results help resolve some current debates about the role of conscious awareness in sequence learning. (shrink)

Block () highlights two experimental studies of neglect patients which, he contends, provide ‘dramatic evidence’ for unconscious seeing. In Block's hands this is the highly non-trivial thesis that seeing of the same fundamental kind as ordinary conscious seeing can occur outside of phenomenal consciousness. Block's case for it provides an excellent opportunity to consider a large body of research on clinical syndromes widely held to evidence unconscious perception. I begin by considering in detail the two studies of neglect to which (...) Block appeals. I show why their interpretation as evidence of unconscious seeing faces a series of local difficulties. I then explain how, even bracketing these issues, a long-standing but overlooked problem concerning our criterion for consciousness problematizes the appeal to both studies. I explain why this problem is especially pressing for Block given his view that phenomenal consciousness overflows access consciousness. I further show that it is epidemic—not only affecting all report-based studies of unconscious seeing in neglect, but also analogous studies of the condition most often alleged to show unconscious seeing, namely blindsight. (shrink)

We briefly presented either the letter ‘b’ or the letter ‘h’ to participants who were instructed to respond by saying the letter that was not shown. This binary version of the exclusion task avoids problems with assessing baseline completion rates. When the letters were shown for 5–10 ms participants erroneously responded with the shown letter at a rate greater than chance. They were capable of following the instructions when the letter was shown for longer . Given the chance to wager (...) low or high on their choices after short duration stimuli, participants declined to wager high even when they were correct. Taken together these results suggest that the briefly presented stimuli were processed subconsciously. (shrink)

Methodological problems of how awareness during learning should be measured have been extensively discussed and investigated in cognitive psychology. This review considers; 1)whether amnesics can perform implicit learning tasks at a similar level to normal controls, 2) whether differences in instructional orientations create dissociations in performance in tests of implicit and explicit knowledge, and 3) whether participants can retrospectively verbalise the learning outcomes. The paper concludes that; amnesics’ implicit learning abilities differ from the normal controls, instructions on implicit learning do (...) not guarantee the occurrence of implicit learning, and objective and subjective awareness measures used in the literature face inherent problems and so the awareness controversy remains unsettled. (shrink)

People have intuitively assumed that many acts of volition are not influenced by unconscious information. However, the available evidence suggests that under suitable conditions, unconscious information can influence behavior and the underlying neural mechanisms. One possibility is that stimuli that are consciously perceived tend to yield strong signals in the brain, and this makes us think that consciousness has the function of sending such strong signals. However, if we could create conditions where the stimuli could produce strong signals but not (...) the conscious experience of perception, perhaps we would find that such stimuli are just as effective in influencing volitional behavior. (shrink)

Three experiments examined the role of response criteria in a masked semantic priming paradigm using an exclusion task. Experiment 1 used on-line prime-report and exclusion instructions in which participants were told to avoid completing a word stem with a word related to a prime flashed for 0, 38 or 212 ms. Semantic priming was significant in the items analysis, but was moderated by peoples’ ability to report the prime in the participant analysis. Prime-report thresholds in Experiment 2 were made more (...) liberal by instructing participants to guess on every trial. Prime-report increased from Experiment 1 as exclusion failures were eliminated. Experiment 3 clarified the relationship between awareness and prime identification using an on-line measure of confidence and different liberal prime report instructions. The current findings suggest that the ability to act upon and report information in a masked prime is determined by a variable response criterion, which can be manipulated as an independent variable. (shrink)

It is a common conviction among philosophers who hold that phenomenal properties, qualia, are distinct from any cognitive, intentional, or functional properties, that it is possible to trace the neural correlates of these properties. The main purpose of this paper is to present a challenge to this view, and to show that if “non-cognitive” phenomenal properties exist at all, they lie beyond the reach of neuroscience. In the final section it will be suggested that they also lie beyond the reach (...) of psychology, so that they may be said to lie beyond the reach of science. (shrink)

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 . 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. (shrink)

Unconscious processes, by whatever name they may be known , are invariably operationalized by the dissociation paradigm, any situation involving the dissociation between two indicators , one of availability and the other, of accessibility , such that, ε>α. Subliminal perception has been traditionally defined by a special case of the dissociation paradigm in which availability exceeds accessibility when accessibility is null . Construct validity issues bedevil all dissociation paradigms since it is not clear what might constitute appropriate indicators that, moreover, (...) are pure and exhaustive. Semantic and theoretic drifts in the recent literature—e.g., the confusion of different versions of the dissociation paradigm, the equation of conscious–unconscious with direct–indirect tests, and the foisting of the criterion of qualitative differences—have tended to undermine emerging theoretic parsimony. On the other hand, a crucial factor has been left out of theory development: time. Both ε and α can rise and fall over time, often asynchronously, and so dissociations may wax and wane and, even, reverse over time. Some laboratory evidence suggests that accessibility measures , as they approach chance, may actually dip below chance . If so, d′=0 , could be an averaging artifact of positive and negative d′s. Conscious accessibility is not either–or but more or less, and variable over time. (shrink)

Block [Block, N. . Two neural correlates of consciousness. Trends in Cognitive Science, 9, 46–52] and Snodgrass claim that a signal detection theory 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 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. (shrink)

In this response to 32 commentators, I start by clarifying the overflow argument. I explain why the distinction between generic and specific phenomenology is important and why we are justified in acknowledging specific phenomenology in the overflow experiments. Other issues discussed are the relations among report, cognitive access, and attention; panpsychic disaster; the mesh between psychology and neuroscience; and whether consciousness exists.

How can we disentangle the neural basis of phenomenal consciousness from the neural machinery of the cognitive access that underlies reports of phenomenal consciousness? We can see the problem in stark form if we ask how we could tell whether representations inside a Fodorian module are phenomenally conscious. The methodology would seem straightforward: find the neural natural kinds that are the basis of phenomenal consciousness in clear cases when subjects are completely confident and we have no reason to doubt their (...) authority, and look to see whether those neural natural kinds exist within Fodorian modules. But a puzzle arises: do we include the machinery underlying reportability within the neural natural kinds of the clear cases? If the answer is ‘Yes’, then there can be no phenomenally conscious representations in Fodorian modules. But how can we know if the answer is ‘Yes’? The suggested methodology requires an answer to the question it was supposed to answer! The paper argues for an abstract solution to the problem and exhibits a source of empirical data that is relevant, data that show that in a certain sense phenomenal consciousness overflows cognitive accessibility. The paper argues that we can find a neural realizer of this overflow if assume that the neural basis of phenomenal consciousness does not include the neural basis of cognitive accessibility and that this assumption is justified by the explanations it allows. (shrink)

Some theorists have recently raised doubts about much of the experimental evidence purporting to demonstrate the existence of unconscious perception. In our (2019) in this journal, we argued some of these considerations are not decisive. Phillips (forthcoming a) replies thoughtfully to our paper, concluding that he is unconvinced by our arguments. Phillips maintains that the view that perception is invariably conscious remains, as he puts it, the “default” hypothesis both within the folk understanding and experimental study of perception. There is (...) much to agree with in Phillips’ piece, but there remain some substantive points of disagreement, which we outline here. (shrink)

The authors report "priming" effects for subjects they classify as "inattentionally blind" and interpret this as evidence for unconscious perception--an interpretation consistent with deeply entrenched metatheory. I question that interpretation, however, on methodological grounds. On these assessment procedures, some subjects could be classified as "inattentionally blind" despite representing the critical stimulus in conscious attention. Still others--presenting a more interesting challenge--could be so classified despite representing the stimulus literally in inattentional awareness. The study is illuminated, I believe, by seeing it in (...) metatheoretical and experimental contexts, with its theoretical interpretation contrasted with an alternative. (shrink)