Alan Chauvin

Laboratoire de Psychologie et Neurocognition
CNRS UMR 5105
Université Pierre Mendès-France
Bâtiment Sciences de l'Homme et Mathématiques
BP47, 38040 Grenoble Cedex 9 France

Tél. : (+33)(0)4-76-82-59-26


Alan.Chauvin@upmf-grenoble.fr

Manipulating saccadic reaction time

Studies of reaction-time distributions provide a useful quantitative approach to understand decision processes at the neural level and at the behavioral level. A strong relationship between the spread of latencies and the median is generally accepted even though there has been no attempt to disentangle experimentally these two parameters. Here we test the ability to independently control the median and the variability in reaction times. Our results demonstrate that learned contingencies can affect reaction time variability and support the view that the so-called noise level in decision processes can undergo long-term changes.

Madelain, L., L. Champrenaut, and A. Chauvin, Control of sensorimotor variability by consequences. J Neurophysiol, 2007. 98(4): p. 2255-65.

Madelain, L., Champrenault, L. & Chauvin, A. (2007) Control of sensorimotor variability, Perception, 36, ECVP Abstract Supplement

Madelain, L., Champrenault, L. & Chauvin, A. (2007) Control of sensorimotor variability, Journal of Vision, [Abstract VSS], http://journalofvision.org/7/9/32/

Using simulation improve perceptual sensitivity

We conducted Ttwo experiments addressing the issue of whether observing (visual priming) or producing (motor priming) running activity during a very short period (30 s) facilitates the perception of the direction of a point-light runner embedded in a dense dynamical mask. These findings argue in favour of common representation for the perception and the production of human movement and showed that biological motion processing can be improved by prior motor activity either performed or observed

Bidet-Ildei, C., Chauvin, A., & Coello, Y. (2009) Prior observation or production of a motor action improves the perception of biological motion: Evidence for a gender effect, ECVP Abstract Supplement

Bidet-Ildei, C., Chauvin, A., & Coello, Y. (2009) Motricité et perception visuelle des mouvements humains : effet d'amorçage et influence du sexe " congres de la SFP toulouse 2009 : " Psychologie et enjeux de société " 17-19 juin 2009

Bidet-Ildei, C., Chauvin, A., & Coello, Y. (2009) Percevoir l'imperceptible par l'action : l'exemple du mouvement biologique, 3ième Forum du GDR-vision Faculté de Médecine de Rangueil, jeudi 4, vendredi 5 juin 2009

On a different account of the two visual streams

By assessing the effect of near threshold stimuli on both perceptual and motor responses, recent studies challenged the dominant dual-vision theory suggesting distinct processing for perception and action. Cardoso-Leite & Gorea (2009) for instance showed that saccadic curvature induced by the presence of near threshold distractors depends on the actor's perceptual state, suggesting a lack of independence between perception and action. The aim of the present study is to provide a direct test of this assumption in a perceptual-motor dual task. This study overall support the proposal of a unique signal used for perceptual and motor decisions and suggests a perceptual state dependent excitatory process in target selection

Deplancke, A., Madelain, L., Chauvin, C., Coello, Y (2009) Effects of a distractor on a manual reaching task : evidence for no dissociation between perception and action. Computational principles of sensorimotor learning, Kloster Irsee, Germany, September 13-15 2009

Deplancke, A., Madelain, L., Chauvin, C., Coello, Y (2009) L'effet de distracteurs spatiaux lors de réponses visuo-motrices dépend de leur détection : arguments en faveur d'une absence de dissociation entre perception et action " congres de la SFP toulouse 2009 : " Psychologie et enjeux de société " 17-19 juin 2009

A review and a chapter on Eye movements

A review on the pre motor theory of attention and a paper on the exploration of a document than contain both text and images

Madelain, L and Chauvin, A. Attention et saccades. In: L'attention visuelle, edited by Michael G, 2008.

Chauvin, A. & Sparrow, L. (2008). Lecture et exploration oculaire: intégration du texte et de l'image. In Information & visualisation. Toulouse : Editions Cépaduès

Natural Scenes Categorisation

With N. Guyader

Models of the visual cortex are based on image decomposition according to the Fourier spectrum (amplitude and phase). On one hand, it is commonly believed that phase information is necessary to identify a scene. On the other hand, it is known that complex cells of the visual cortex, the most numerous ones, code only the amplitude spectrum. This raises the question of knowing if these cells carry sufficient information to allow visual scene categorization. In this work, using the same experiments in computer simulation and in psychophysics, we provide arguments to show that the amplitude spectrum alone is sufficient for categorization task.

Guyader, N., Chauvin, A., Peyrin, C., Hérault, J., & Marendaz, C. (2004). Image phase or amplitude? Rapid scene categorization is an amplitude based process. C. R. Biologies 327,313-318.

Chauvin, Guyader, Marendaz, Hérault (2002) Argument for scene categorisation with image amplitude spectra, ECVP poster html

Guyader, N., Chauvin, A., Bert, L., Mermillod, M., Hérault, J. & Marendaz, C. (2005) Rapid Visual Scene Categorization Relies Mainly on Amplitude Spectrum, Association for Research and Vision in Opthalmology ARVO 2005

Other work on categorisation with Martial Mermilod and Nathalie Guyader<

Guyader, N., Chauvin, A., Massot, C., Hérault, J., & Marendaz, C. (2006). A biological model of low-level vision suitable for image analysis and cognitive visual perception. Perception, 35, ECVP Abstract Supplement.

Mermillod M., Guyader N. & Chauvin A. (2005). Improving generalisation skills in a neural network on the basis of neurophysiological data. Brain & Cognition, 58(2), 246-248

Mermillod M., Guyader N. & Chauvin A. (2005). The Coarse-to-fine Hypothesis Revisited: Evidence from Neuro-Computational Modeling. Brain & Cognition, 57(2), 151-157.

Mermillod M., Chauvin A., Guyader N. (2004). Efficiency of Orientation Channels in the Striate Cortex for Distributed Categorization Process. Brain & Cognition, 55(2), 352-354.

Mermillod M., Guyader N. & Chauvin A. (2004). Does the energy spectrum from Gabor wavelet filtering represent sufficient information for neural network recognition and classification tasks? In H. Bowman, C. Labiouse (Eds.) Connectionist Models of Cognition, Perception and Emotion II. Progress in Neural Processing (vol. 15). World Scientific, pp 148-156.

French, R. M., Mermillod, M., Quinn, P. C., Chauvin, A., & Mareschal, D. (2002). The Importance of Starting Blurry: Simulating Improved Basic-Level Category Learning in Infants Due to Weak Visual Acuity. Proceedings of the 24th Annual Conference of the Cognitive Science Society. NJ:LEA. 322-327.

Other work on categorisation with Carole Peyrin

Peyrin, C., Chauvin, A., Chokron, S., & Marendaz, C. (2003). Hemispheric specialization for spatial frequency processing in the analysis of natural scenes. Brain and Cognition, 53 (2), 278-282.

Ballaz, C., Marendaz, C., Chauvin, A. & Peyrin, C.(2001) L'orientation canonique comme déterminant de la saillance perceptive. In Cognito, 22, 37-46

Saliency Map

Eye movements, Natural Scenes, saliency map and causality

Do image properties drive first ocular explorations of natural scene during free viewing? The response is positive, according to previous works defining image properties with statistical measures or modeled with a saliency map. But, because these works were mainly based on correlation analysis (but see Einhauser, 2002), no causal link could be established between image properties and ocular fixations.

Therefore, across three experiments (180 subjects) we manipulated the saliency and semantic congruency of small regions within 72 natural scenes during a categorization task. In the 'saliency' experiment, the mean saliency of one region was reduced for half the scenes. In the 'semantic' experiment, an incongruent object (object with a very low probability of occurrence in the scene context) was introduced.

In conclusion, on one hand; we establish a causal link between saliency and ocular fixations. On the other hand; keeping most of image properties constant, we show that ocular fixations are flexibly driven by the congruency of an object and its context. Incongruent object were less attractive during the first moment of exploration, in contrary to longer exploration.

This work was mainly presented in oral form during ECVP in Glasgow, VSS and ESCOP at Marseille

Chauvin, A., Guyader, N. Hérault, J. & Marendaz, C., (2007) Flexible uses of saliency map during ocular explorations of real-world scenes. 15ème conference de l'European Society for Cognitive Psychology, Marseille, France.

Marendaz, C., Chauvin, A., & Hérault, J. (2005). A causal link between scene exploration, local saliency and scene context [Abstract]. Journal of Vision, 5(8), 919a, http://journalofvision.org/5/8/919/, doi:10.1167/5.8.919.

Chauvin, A., Hérault, J., & Marendaz, C. (2002). Natural Scene Perception : Visual Attractors and Images Processing. In John A. Bullinaria & Will Lowe (Eds), Connectionist Models of Cognition and Perception. (pp. 236-245). Singapore: World Scientific.

Post-Doc – CERNEC, F. Gosselin and M. Arguin

face inversion effect

Willenbockel, V., Fiset, D., Chauvin, A., Blais, C. Arguin, M., Tanaka, J., Bub, D. & Gosselin, F. (in press). Does face inversion change spatial frequency tuning? Journal of Experimental Psychology: Human Perception and Performance.

Time x Spatial Frequencies classification images

With D. Fiset, E. Mc Cabe, N. Dupuy-Roy and C. Blais  under the direction of F. Gosselin and M. Arguin

These works were presented at the annual meeting of the Vision Science Society in Sarasota 2005.

Blais, C., Fiset, D., Chauvin, A., Arguin, M., & Gosselin, F. (2005). The effective use of spatial frequencies through time in reading [Abstract]. Journal of Vision, 5(8), 813a, http://journalofvision.org/5/8/813/, doi:10.1167/5.8.813.

Chauvin, A., Fiset, D., Ethier, C., Tadros, K., Arguin, M., & Gosselin, F. (2005). Spatial frequency streams in natural scene categorization [Abstract]. Journal of Vision, 5(8), 603a, http://journalofvision.org/5/8/603/, doi:10.1167/5.8.603.

McCabe, É., Chauvin, A., Fiset, D., Arguin, M., & Gosselin, F. (2005). The use of spatial frequency through time in face identification [Abstract]. Journal of Vision, 5(8), 988a, http://journalofvision.org/5/8/988/, doi:10.1167/5.8.988

Fiset, D., Chauvin, A., Dupuis-Roy, N., Blais, C., Arguin, M., & Gosselin, F. (2005). Use of spatial frequencies information in normal readers and a letter-by-letter dyslexic patient [Abstract]. Journal of Vision, 5(8), 811a, http://journalofvision.org/5/8/811/, doi:10.1167/5.8.811.

Statistics for classification images

Chauvin, A., Worsley, K. J., Schyns, P. G., Arguin, M., & Gosselin, F. (2005). Accurate statistical tests for smooth classification images. Journal of Vision, 5(9), 659-667, http://journalofvision.org/5/9/1/ , doi:10.1167/5.9.1.

The toolbox is available on line : Link to the site web page

Gosselin, F., Chauvin, A., Worsley, K. J., Schyns, P. G., & Arguin, M. (2005). A statistics toolbox for classification images [Abstract]. Journal of Vision, 5(8), 480a, http://journalofvision.org/5/8/480/ , doi:10.1167/5.8.480.

Facial emotions

Cousin, S., Rivière, V., Chauvin, A., & Darcheville J.-C. (2008). Facial expression discrimination in children with autism (2008). Paper presented at the IV conference of the EABA, Madrid (Spain).

Cousin, S., Riviere, V., Chauvin, A., & Darcheville J.C. (2008) Analysis of information used to discriminate facial expressions by 2 children with autism : a preliminary study ABAI 2008 Autism Conference, feb 2008.

Rivière, V. Darcheville, J.C., Chauvin, A. & Cousin, S. (2007). Study of facial expressions discrimination in children with autism. San Diego. 33th Annual Convention of the Association of Behavior Analysis. May