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)

Here Jean-Pierre Changeux elucidates our current knowledge of the human brain, taking an interdisciplinary approach and explaining in layman's terms the complex theories and scientific breakthroughs that have significantly improved our ...

In a remarkable exchange between neuroscientist Jean-Pierre Changeux and philosopher Paul Ricoeur, this book explores the vexed territory between these...

1 INSERM-CEA Unit 562, Cognitive Neuroimaging, Service Hospitalier Fre´de´ric Joliot, Orsay, France, 2 CNRS URA2182 Re´cepteurs and Cognition, Institut Pasteur, Paris, France.

This paper investigates the compatibility between the theoretical framework of the global neuronal workspace theory (GNWT) of conscious processing and the perturbational complexity index (PCI). Even if it has been introduced within the framework of a concurrent theory (i.e. Integrated Information Theory), PCI appears, in principle, compatible with the main tenet of GNWT, which is a conscious process that depends on a long-range connection between different cortical regions, more specifically on the amplification, global propagation, and integration of brain signals. Notwithstanding (...) this basic compatibility, a number of limited compatibilities and apparent differences emerge. This paper starts from the description of brain complexity, a notion that is crucial for PCI, to then summary of the main features of PCI and the main tenets of GNWT. Against this background, the text explores the compatibility between PCI and GNWT. It concludes that GNWT and PCI are fundamentally compatible, even though there are some partial disagreements and some points to further examine. (shrink)

"This wonderfully eloquent and playful colloquy of two brilliant minds gives new life to the old notion of Dialogue, a sadly forgotten form now.... I "love" this book!

An eminent neurobiologist reflects on the human brain, connecting recent scientific findings with ideas from an array of other disciplines.

Aborde de nombreux thèmes, notamment : la vérité en mathématiques, la construction du vrai dans le développement cognitif de l'enfant, la procédure de Ramsey et le problème du réalisme scientifique, les relations de l'astrophysique et de la cosmologie avec l'observation.

« Toute activité se laisse discerner et définir dans la mesure où elle prend forme, où elle inscrit sa courbe dans l’espace et le temps. La vie agit essentiellement comme créatrice de formes. La vie est forme, et la forme est le mode de la vie » (Henri Focillon). Formes de la géométrie et du cosmos, formes de la vie et de la pensée, formes architecturales, musicales et littéraires, formes fixes ou métamorphoses : le concept de forme est omniprésent dans (...) les sciences et dans les arts. C’est à une exploration de cette notion de forme que le Collège de France a consacré en octobre 2011 son colloque multidisciplinaire de rentrée : sa définition en philosophie chez Platon et Aristote, ses applications en mathématiques et en astrophysique, en chimie et en biologie, ses conséquences en psychologie et en linguistique, en anthropologie, en droit et dans les arts. Ces débats ont été aussi l’occasion de se tourner vers des pensées où elle joue un rôle particulièrement important, comme le structuralisme de Claude Lévi-Strauss ou l’histoire de l’art d’André Chastel. Jean-Pierre Changeux est professeur honoraire au Collège de France, chaire de Communications cellulaires. Il a dirigé la publication de trois colloques précédents du Collège de France : La Vérité dans les sciences (2003), Gènes et culture (2003) et L’Homme artificiel(2007). Contributions de Antoine Compagnon, Claude Debru, Stanislas Dehaene, Mireille Delmas-Marty, Philippe Descola, Anne Fagot-Largeault, Marcel Hénaff, Michel Hochmann, Jean-Jacques Hublin, François-Bernard Mâche, Jean-François Mangin, Jean-Claude Pecker, Jacques Reisse, John Scheid, Jesper Svenbro. (shrink)

The structure and behaviour of the acetylcholine receptor (AChR) is described, and the evidence that it is an allosteric protein is discussed. The genes for the AChR subunits are subject to a complex set of spatio‐temporal transcriptional controls during development of the motor endplate, and these findings are reviewed here. Finally, the biotechnological prospects suggested by the new data are noted.