Amidst the many brain events evoked by a visual stimulus, which are specifically associated with conscious perception, and which merely reflect non-conscious processing? Several recent neuroimaging studies have contrasted conscious and non-conscious visual processing, but their results appear inconsistent. Some support a correlation of conscious perception with early occipital events, others with late parieto-frontal activity. Here we attempt to make sense of those dissenting results. On the basis of a minimal neuro-computational model, the global neuronal workspace hypothesis, we propose a (...) taxonomy which distinguishes between vigilance and access to conscious report, as well as between subliminal, preconscious and conscious processing. We suggest that these distinctions map onto different neural mechanisms, and that conscious perception is systematically associated with a sudden surge of parieto-frontal activity causing top-down amplification. (shrink)

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Cognitive science is a child of the 1950s, the product of a time when psychology, anthropology and linguistics were redefining themselves and computer science and neuroscience as disciplines were coming into existence. Psychology could not participate in the cognitive revolution until it had freed itself from behaviorism, thus restoring cognition to scientific respectability. By then, it was becoming clear in several disciplines that the solution to some of their problems depended crucially on solving problems traditionally allocated to other disciplines. Collaboration (...) was called for: this is a personal account of how it came about. (shrink)

Consider the following three situations: learning to perform a complex skill such as gymastics (a stunning demonstration of which participants to ICP 2004 experienced during the opening ceremony), learning a complex game such as the ancient Chinese game of Weichi (more widely known as Go), or learning natural language. What these situations have in common, beyond the sheer complexity of the required skills, is the fact that most of what we learn about each appears to proceed in a manner that (...) does not depend so much on the acquisition of explicit, declarative information or on the deployment of intentional strategies, but instead critically depends on repeated practice: Developing the skills needed to execute complex movements in gymnastics, to. (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)

Au XIXe siècle, la question de la relation de l'âme au corps est profondément renouvelée par les travaux psychologiques allemands. Cette nouvelle manière d'envisager le rapport du psychique au physique participe de l’apparition d’un paradigme cognitiviste où les phénomènes mentaux sont considérés comme des entités isolables, objectivables et corrélables à l’activité de substrats neuraux particuliers. Les psychologues allemands sont confrontés au problème de la corrélation de la vie psychique et du système nerveux (localisation des phénomènes mentaux et nature de ce (...) rapport de corrélation) et proposent une réflexion approfondie sur le déterminisme neural et l’émergence des processus psychiques. (shrink)