The resurgent science of consciousness has been accompanied by a recent emphasis on the problem of measurement. Having dependable measures of consciousness is essential both for mapping experimental evidence to theory and for designing perspicuous experiments. Here, we review a series of behavioural and brain-based measures, assessing their ability to track graded consciousness and clarifying how they relate to each other by showing what theories are presupposed by each. We identify possible and actual conflicts among measures that can stimulate new (...) experiments, and we conclude that measures must prove themselves by iteratively building knowledge in the context of theoretical frameworks. Advances in measuring consciousness have implications for basic cognitive neuroscience, for comparative studies of consciousness and for clinical applications. (shrink)
In their comment on Sandberg, Timmermans, Overgaard, and Cleeremans (2010), Dienes and Seth argue that increased sensitivity of the Perceptual Awareness Scale (PAS) is a consequence of the scale being less exclusive rather than more exhaustive. According to Dienes and Seth, this is because PAS may measure some conscious content, though not necessarily relevant conscious content, ‘‘If one saw a square but was only aware of seeing a flash of something, then one has not consciously seen a square.” In this (...) reply, we claim that there is a difference between conscious visual experience, which may be partial, and the resulting conscious content, which is conceptual. Whereas PAS measures the first, confidence judgments and post-decision wagering measure the second. (shrink)
Blindsight is classically defined as residual visual capacity, e.g., to detect and identify visual stimuli, in the total absence of perceptual awareness following lesions to V1. However, whereas most experiments have investigated what blindsight patients can and cannot do, the literature contains several, often contradictory, remarks about remaining visual experience. This review examines closer these remarks as well as experiments that directly approach the nature of possibly spared visual experiences in blindsight.
Dienes and Seth (2010) conclude that confidence ratings and post-decision wagering are two comparable and recommendable measures of conscious experience. In a recently submitted paper, we have however found that both methods are problematic and seem less suited to measure consciousness than a direct introspective measure. Here, we discuss the methodology and conclusions put forward by Dienes and Seth, and why we think the two experiments end up with so different recommendations.
Several authors within psychology, neuroscience and philosophy take for granted that standard empirical research techniques are applicable when studying consciousness. In this article, it is discussed whether one of the key methods in cognitive neuroscience – the contrastive analysis – suffers from any serious confounding when applied to the field of consciousness studies; that is to say, if there are any systematic difficulties when studying consciousness with this method that make the results untrustworthy. Through an analysis of theoretical arguments in (...) favour of using contrastive analysis, combined with analyses of empirical findings, I conclude by arguing for three factors that currently are confounding of research using contrastive analysis. These are (1) unconscious processes, (2) introspective reports, and (3) attention. (shrink)
In the attempt to construct a scientific approach to consciousness, it has been proposed that transcendental phenomenology or phenomenological psychology be introduced into the framework of cognitive neuroscience. In this article, the consequences of such an approach in terms of basic assumptions, methods for the collection of data, and evaluation of the collected data are discussed. Especially, the proposed notions of mutual constraint and the second perso are discussed. It is concluded that even though naturalising of phenomenology might not prove (...) impossible, the projec has not yet found a coherent basic ground. (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)
One supposition underlying the Anderson & Lebiere (A&L) target article is that the maximally broad “encompassing of its subject matter – the behavior of man” (cf. sect. 6, last para.) is regarded as an unquestioned quality criterion for guiding cognitive research. One might argue for an explicit specification of the limitations of a given paradigm, rather than extending it to apply to as many domains as possible.
This article presents the view that the problem of consciousness per definition can not be seen as a strictly scientific or strictly philosophical problem. The first idea, especially, leads to important difficulties: First of all, the idea has in most cases implied some rather superficial reductionistic or functionalistic a priori assumptions, and, secondly, it can be shown that some of the most commonly used empirical methods in these regards are inadequate. Especially so in the case of contrastive analysis, (...) widely used in cognitive neuroscience. However, this criticism does not lead to the conclusion that scientific methods are inadequate as such, only that they always work on a pre-established background of theory, of which one must be explicit. (shrink)