Consciousness can be measured in various ways, but different measures often yield different conclusions about the extent to which awareness relates to performance. Here, we compare five different subjective measures of awareness in the context of an artificial grammar learning task. Participants expressed their subjective awareness of rules using one of five different scales: confidence ratings , post-decision wagering , feeling of warmth , rule awareness , and continuous scale . All scales were equally sensitive to conscious knowledge. PDW, however, (...) was affected by risk aversion, and both RAS and SDS applied different minimal criteria for rule awareness. CR seems to capture the largest range of consciousness, but failed to indicate unconscious knowledge with the guessing criterion. We close by discussing the theoretical implications of scale sensitivity and propose that CR’s unique features enable a finer assessment of subjective states of awareness. (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)

We explore three methods for measuring the conscious status of knowledge using the artificial grammar learning paradigm. We show wagering is no more sensitive to conscious knowledge than simple verbal confidence reports but is affected by risk aversion. When people wager rather than give verbal confidence they are less ready to indicate high confidence. We introduce a “no-loss gambling” method which is insensitive to risk aversion. We show that when people are just as ready to bet on a genuine random (...) process as their own classification decisions, their classifications are still above baseline, indicating knowledge participants are not aware of having. Our results have methodological implications for any study investigating whether people are aware of knowing. (shrink)

Post-decision wagering has been proposed as a method of demonstrating that perception can occur without conscious awareness. When wagering is independent from above-chance performance there is evidence of a lack of awareness of the correctness of the first-order discriminations. However, there are reasons to believe that the contingency analysis conducted by Persaud and colleagues failed to measure “the zero accuracy-wagering criterion”. The author shows that a Pearson chi-square test employed by Persaud and colleagues is unable to accommodate the hypothesis of (...) partial independence between accuracy and advantageous wagering. On the contrary, the problem of “the zero accuracy-wagering criterion” is best conducted with log-linear models. Moreover, log-linear analysis suggests that absence of advantageous wagering is not sufficient evidence for a lack of conscious awareness. In the case of the blindsight study, there was compelling evidence that the patient GY was partially aware of having information about the correctness of his decisions. (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)

Subliminal perception (SP) is today considered a well-supported theory stating that perception can occur without conscious awareness and have a significant impact on later behaviour and thought. In this article, we first present and discuss different approaches to the study of SP. In doing this, we claim that most approaches are based on a dichotomic measure of awareness. Drawing upon recent advances and discussions in the study of introspection and phenomenological psychology, we argue for both the possibility and necessity of (...) using an elaborated measure of subjective states. In the second part of the article, we present findings where these considerations are implemented in an empirical study. The results and implications are discussed in detail, both with reference to SP, and in relation to the more general problem of using elaborate introspective reports as data in relation to studies of cognition. (shrink)

In a recent article, [Sergent, C. & Dehaene, S. . Is consciousness a gradual phenomenon? Evidence for an all-or-none bifurcation during the attentional blink, Psychological Science, 15, 720–729] claim to give experimental support to the thesis that there is a clear transition between conscious and unconscious perception. This idea is opposed to theoretical arguments that we should think of conscious perception as a continuum of clarity, with e.g., fringe conscious states [Mangan, B. . Sensation’s ghost—the non-sensory “fringe” of consciousness, Psyche, (...) 7, 18]. In the experimental study described in this article, we find support for this opposite notion that we should have a parsimonious account of conscious perception. Our reported finding relates to the hypothesis that there is more than one perceptual threshold [Merikle, P.M., Smilek, D. & Eastwood, J.D. . Perception without awareness: perspectives from cognitive psychology, Cognition, 79, 115–134], but goes further to argue that there are different “levels” of conscious perception. (shrink)

When the stored representation of the meaning of a stimulus is accessed through the processing of a sensory input it is maintained in an activated state for a certain amount of time that allows for further processing. This semantic activation is generally accompanied by conscious identification, which can be demonstrated by the ability of a person to perform discriminations on the basis of the meaning of the stimulus. The idea that a sensory input can give rise to semantic activation without (...) concomitant conscious identification was the central thesis of the controversial research in subliminal perception. Recently, new claims for the existence of such phenomena have arisen from studies in dichotic listening, parafoveal vision, and visual pattern masking. Because of the fundamental role played by these types of experiments in cognitive psychology, the new assertions have raised widespread interest. (shrink)

Research on consciousness is currently enjoying a spectacular revival of interest in the cognitive sciences. From an empirical point of view, the NCC program — the search for the “Neural Correlates of Consciousness” — holds the promise of establishing correlations between physiological and phenomenal states in a way that directly resembles G. T. Fechner´s (1860) so-called “inner psychophysics”. Should the NCC program be entirely successful, we would thus be able to predict phenomenal states based on physiological states. we would be (...) able to predict phenomenal states based on physiological states. In this paper, we explore some of the conceptual and methodological difficulties of this approach. In both neurobiology and psychology, there are serious measurement problems that stand in the way of correlation research, even after the “hard problem” has been set aside. Thus, even if one had identified certain internal functional states as indicators of phenomenal states, the empirical psychologist would still be confronted with fundamental problems, such as determining the absence or presence of these functional states. In this respect, philosophy of science may help and provide a metatheoretical framework for the current interdisciplinary project. (shrink)

Conscious access to fear-relevant information is mediated by threshold The present report proposed a model of access consciousness to fear-relevant information according to which there is a threshold for emotional perception beyond that the subject makes hits with no false alarm. The model was examined by having the participants performed a confidence-ratings masking task with fearful faces. Measures of the thresholds for conscious access were taken by looking at the receiver operating characteristics curves generated from a three-state low- and high-threshold (...) model by Krantz. Indeed, the analysis of the masking data revealed that the ROCs had threshold-like-nature rather continuous challenging in this fashion the classical signal-detection view on perceptual processing. Moreover, the threshold ROC curve exhibited the specific y-intercepts relevant to conscious access performance. The study suggests that the threshold can be an intrinsic property of conscious access, mediating emotional contents between perceptual states and consciousness. (shrink)