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1	Modelling the spatial tuning of the Hermann grid illusion. Cox, Michael J., Ares-Gomez, J.B., Pacey, Ian E., Gilchrist, James M., Mahalingam, Ganeshbabu T. January 2007 (has links) No / Purpose: Does a physiologically plausible model of the retinal ganglion cell (RGC) receptive field (RF) predict the spatial tuning properties of the Hermann Grid Illusion (HGI)? Methods: The spatial tuning of a single intersection HGI was measured psychophysically in normal observers using a nulling technique at different vertical grid line luminances. We used a model based upon a standard RGC RF, balanced to produce zero response under uniform illumination, to predict the response of the model cell to the equivalent range of stimulus conditions when placed in either the 'street' or the 'intersection' of a single element of a Hermann grid. We determined the equivalent of the nulling luminance required to balance these responses and minimise the HGI. Results: The model and the psychophysical data demonstrated broad spatial tuning with similarly shaped tuning profiles and similar strengths of illusion. The line width at the peak of the model tuning function was around twice the model RGC RF centre size. Modelling the psychophysical functions gave RF centre sizes smaller than expected from human anatomical evidence but similar to that suggested by primate physiological evidence. In the model and psychophysically the strength of the illusion varied with the luminance of the vertical grid line when HGI strength was expressed as a Michelson nulling contrast, but this effect was smaller when HGI strength was expressed as a nulling luminance. Conclusions: The shape, width, height and position of the spatial tuning function of the HGI can be well modelled by a RGC RF based model. The broad tuning of these functions does not appear to require a broad range of different cell sizes either in the retina or later in the visual pathway. Retinal ganglion cell Hermann grid illusion Spatial tuning Perceptive field Visual psychphysics
2	Relations du texte à l'image et au son dans le cadre d'une fiction littéraire interactive / Relation between text, image and sound within interactive literary fiction Bouillot, Daniel 05 October 2012 (has links) L’essor du numérique et la multiplication des supports (smartphone, tablette tactile)ouvrent de nouvelles perspectives en matière d’écriture. Dans ce monde où textes, images et sons s’entrecroisent au fil des réseaux et au gré de l’interactivité, la fiction littéraire peut-elle trouver une voie qui lui permette de préserver sa richesse tout en bénéficiant des apports du numérique ? Comment l’auteur littéraire peut-il concevoir et agencer ses matériaux narratifs afin de toucher efficacement des lecteurs disposés à franchir le pas du numérique ? Quels sont les fondements d’une narration multimodale utilisant au mieux les potentiels du texte, de l’image et du son, dans toute leur complémentarité, pour servir une fiction littéraire destinée à un large public ? Ces questions sont abordées, tant du point de vue de l’auteur que de celui du lecteur, dans une approche transdisciplinaire à la fois théorique et expérimentale. / The intense development of digital technologies and hardware (smartphones, tablets) is opening up new prospects for storytelling. In a world where texts, images and sound intermingle through networks and user interactivity, is it possible for narrative fiction to preserve its great wealth while taking advantage of digital techniques? How can a literary author put together and elaborate his narrative components to effectively reach readers willing to use digital content? What are the foundations of multimodal storytelling that use all the potential of text, image and sound in the best complementary ways to create narrative fiction that can be read by a large public? What balances can be found between "telling" and"showing"? How can interactivity be used to serve the narrative without losing the reader? These issues will be dealt with from both the author's and reader's point of view, in an interdisciplinary approach mixing theory and experimentation. Narration multimodale Fiction littéraire interactive Support numérique Tablette tactile Littérarité Constituants narratifs Champ perceptif Construction narrative Systémique Architecture, navigation, interfaces Spirale production-réception Ecriture littéraire Écriture cinématographique Multimodal storytelling Interactive narrative fiction Digital device Touchscreen tablet Literarity Narrative components Perceptive field Narrative building Systematism Architecture, Browsing, Interfaces Production-Reception Spiral Literary storytelling Cinematographic storytelling 306.48

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Modelling the spatial tuning of the Hermann grid illusion.

Relations du texte à l'image et au son dans le cadre d'une fiction littéraire interactive / Relation between text, image and sound within interactive literary fiction