-
Ehud Ahissar and Amos Arieli.
Figuring space by time.
Neuron,
32:185-201,
2001.
Keywords: perception,
neuroscience,
physiology,
vision,
review.
| Abstract: Sensory information is encoded both in space and in time. Spatial encoding is based on the identity of activated receptors, while temporal encoding is based on the timing of activation. In order to generate accurate internal representations of the external world, the brain must decode both types of encoded information, even when processing stationary stimuli. We review here evidence in support of a parallel processing scheme for spatially and temporally encoded information in the tactile system and discuss the advantages and limitations of sensory-derived temporal coding in both the tactile and visual systems. Based on a large body of data, we propose a dynamic theory for vision, which avoids the impediments of previous dynamic theories. |
| Comments: Brillante explication de la supériorité de l'information temporelle sur l'information "spatialle". refs intéressantes pour la critique de l'oeil-caméra. |
@Article{ahis_arie_01,
author = {Ahissar, Ehud and Arieli, Amos},
title = {Figuring space by time},
journal = {Neuron},
year = {2001},
volume = {32},
pages = {185-201},
comments = {Brillante explication de la supériorité de l'information temporelle sur l'information "spatialle". refs intéressantes pour la critique de l'oeil-caméra.},
keywords = {perception, neuroscience, physiology, vision, review},
rating = {B},
url = {http://www.neuron.org/content/article/abstract?uid=PIIS0896627301004664},
abstract = {Sensory information is encoded both in space and in time. Spatial encoding is based on the identity of activated receptors, while temporal encoding is based on the timing of activation. In order to generate accurate internal representations of the external world, the brain must decode both types of encoded information, even when processing stationary stimuli. We review here evidence in support of a parallel processing scheme for spatially and temporally encoded information in the tactile system and discuss the advantages and limitations of sensory-derived temporal coding in both the tactile and visual systems. Based on a large body of data, we propose a dynamic theory for vision, which avoids the impediments of previous dynamic theories.}
}
-
Anthony Bloch,
Naomi Ehrich Leonard,
and Jerrold E. Marsden.
Controlled Lagrangians and the stabilization of Mechanical Systems I: The First Matching Theorem.
IEEE Trans. on Systems and Control,
45:2253-2270,
2001.
Keywords: motor control,
mechanics,
geometry.
| Abstract: We develop a method for the stabilization of mechanical systems with symmetry based on the technique of controlled Lagrangians. The procedure involves making structured modifications to the Lagrangian for the uncontrolled system, thereby constructing the controlled Lagrangian. The Euler-Lagrange equations derived from the controlled Lagrangian describe the closed-loop system, where new terms in these equations are identified with control forces. Since the controlled system is Lagrangian by construction, energy methods can be used to find control gains that yield closed-loop stability. In this paper we use kinetic shaping to preserve symmetry and only stabilize systems modulo the symmetry group. In the sequel to this paper (Part II), we extend the technique to include potential shaping and we achieve stabilization in the full phase space. The procedure is demonstrated for several underactuated balance problems, including the stabilization of an inverted planar pendulum on a cart moving on a line and an inverted spherical pendulum on a cart moving in the plane. |
@Article{bloc_leon_mars_01,
author = {Bloch, Anthony and Leonard, Naomi Ehrich and Marsden, Jerrold E.},
title = {Controlled Lagrangians and the stabilization of Mechanical Systems I: The First Matching Theorem},
journal = {IEEE Trans. on Systems and Control},
year = {2001},
volume = {45},
pages = {2253-2270},
comments = {superbe. },
keywords = {motor control, mechanics, geometry},
rating = {B},
url = {http://www.princeton.edu/~naomi/cLI.html},
abstract = {We develop a method for the stabilization of mechanical systems with symmetry based on the technique of controlled Lagrangians. The procedure involves making structured modifications to the Lagrangian for the uncontrolled system, thereby constructing the controlled Lagrangian. The Euler-Lagrange equations derived from the controlled Lagrangian describe the closed-loop system, where new terms in these equations are identified with control forces. Since the controlled system is Lagrangian by construction, energy methods can be used to find control gains that yield closed-loop stability. In this paper we use kinetic shaping to preserve symmetry and only stabilize systems modulo the symmetry group. In the sequel to this paper (Part II), we extend the technique to include potential shaping and we achieve stabilization in the full phase space. The procedure is demonstrated for several underactuated balance problems, including the stabilization of an inverted planar pendulum on a cart moving on a line and an inverted spherical pendulum on a cart moving in the plane.}
}
-
Marc Chaperon.
Jets, transversalité, singularités: petite introduction aux grandes idées de René Thom.
actes du colloque international Géométrie au vingtième siècle,
2001.
Keywords: mathematics,
dynamical systems,
catastroph theory.
| Comments: un petit article de vulgarisation. vulgaire, mais génère plein d'intuitions. Rapport expliqué entre potentiel, champs de gradients, et théorie des catastrophes |
@article{chap_01,
author = {Chaperon, Marc},
title = {Jets, transversalité, singularités: petite introduction aux grandes idées de René Thom},
journal = {actes du colloque international Géométrie au vingtième siècle},
year = {2001},
keywords = {mathematics, dynamical systems, catastroph theory},
url = {http://www.math.jussieu.fr/~chaperon/Thom.pdf},
rating = {D},
comments = {un petit article de vulgarisation. vulgaire, mais génère plein d'intuitions. Rapport expliqué entre potentiel, champs de gradients, et théorie des catastrophes}
}
-
R. Goebel,
L. Muckli,
F.E. Zanella,
W. Singer,
and P. Stoerig.
Sustained extrastriate cortical activation without visual awareness revealed by fMRI studies of hemianopic patients.
Vision Research,
3:1459-74,
2001.
Keywords: vision,
perception,
NCC,
awareness.
| Abstract: Patients with lesions in the primary visual cortex (V1) may show processing of visual stimuli presented in their field of cortical blindness even when they report being unaware of the stimuli. To elucidate the neuroanatomical basis of their residual visual functions, we used functional magnetic resonance imaging in two hemianopic patients, FS and GY. In the first experiment, a rotating spiral stimulus was used to assess the responsiveness of dorsal stream areas. Although no response was detectable within denervated or destroyed early visual cortex, motion-sensitive areas (hMT+/V5) ipsilateral to the lesion showed a strong sustained hemodynamic response. In GY, this activation was at least as strong as that of his contralesional hMT+/V5 to the stimulus in the normal hemifield. In the second experiment, coloured images of natural objects were used to assess the responsiveness of ventral stream areas. Again, no activity was detectable in ipsilesional early visual areas, but extrastriate areas in the lateral occipital cortex (hMT+/V5 and LO) and within the posterior fusiform gyrus (V4/V8) showed a robust sustained hemodynamic response. In both experiments, we observed that ipsilesional areas responded to stimuli presented in either hemifield, whereas the normal hemisphere responded preferentially to stimuli in the sighted hemifield. As only one subject occasionally noticed the onset of stimulation in the impaired field, the unexpectedly strong sustained activity in ipsilesional dorsal and ventral cortical areas appears to be insufficient to generate conscious vision. |
| Comments: Certaines lésions de V1 n'empèchent pas un traitement de l'information visuelle, ni l'activation de V5/MT, sans pour autant générer de conscience visuelle. |
@Article{goeb_01,
author = {Goebel, R. and Muckli, L. and Zanella, F.E. and Singer, W. and Stoerig, P.},
title = {Sustained extrastriate cortical activation without visual awareness revealed by fMRI studies of hemianopic patients},
journal = {Vision Research},
year = {2001},
volume = {3},
pages = {1459-74},
abstract = {Patients with lesions in the primary visual cortex (V1) may show processing of visual stimuli presented in their field of cortical blindness even when they report being unaware of the stimuli. To elucidate the neuroanatomical basis of their residual visual functions, we used functional magnetic resonance imaging in two hemianopic patients, FS and GY. In the first experiment, a rotating spiral stimulus was used to assess the responsiveness of dorsal stream areas. Although no response was detectable within denervated or destroyed early visual cortex, motion-sensitive areas (hMT+/V5) ipsilateral to the lesion showed a strong sustained hemodynamic response. In GY, this activation was at least as strong as that of his contralesional hMT+/V5 to the stimulus in the normal hemifield. In the second experiment, coloured images of natural objects were used to assess the responsiveness of ventral stream areas. Again, no activity was detectable in ipsilesional early visual areas, but extrastriate areas in the lateral occipital cortex (hMT+/V5 and LO) and within the posterior fusiform gyrus (V4/V8) showed a robust sustained hemodynamic response. In both experiments, we observed that ipsilesional areas responded to stimuli presented in either hemifield, whereas the normal hemisphere responded preferentially to stimuli in the sighted hemifield. As only one subject occasionally noticed the onset of stimulation in the impaired field, the unexpectedly strong sustained activity in ipsilesional dorsal and ventral cortical areas appears to be insufficient to generate conscious vision.},
comments = {Certaines lésions de V1 n'empèchent pas un traitement de l'information visuelle, ni l'activation de V5/MT, sans pour autant générer de conscience visuelle.},
url = {http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=11322986&dopt=Abstract},
rating = {C},
keywords = {vision, perception, NCC, awareness}
}
-
Anthony Ian Jack and Tim Shallice.
Introspective physicalism as an approach to the science of consciousness..
Cognition,
79(1-2):161-196,
2001.
Keywords: Consciousness,
awareness,
action,
NCC.
| Abstract: Most theories of consciousness are based on vague speculations about the properties of conscious experience. We aim to provide a more solid basis for a science of consciousness. We argue that a theory of consciousness should provide an account of the very processes that allow us to acquire and use information about our own mental states the processes underlying introspection. This can be achieved through the construction of information processing models that can account for Type-C processes. Type-C processes can be specified experimentally by identifying paradigms in which awareness of the stimulus is necessary for an intentional action. The Shallice (1988b) framework is put forward as providing an initial account of Type-C processes, which can relate perceptual consciousness to consciously performed actions. Further, we suggest that this framework may be refined through the investigation of the functions of prefrontal cortex. The formulation of our approach requires us to consider fundamental conceptual and methodological issues associated with consciousness. The most significant of these issues concerns the scientific use of introspective evidence. We outline and justify a conservative methodological approach to the use of introspective evidence, with attention to the difficulties historically associated with its use in psychology. |
| Comments: Mise en perspective de la psycho et des recherches sur la conscience, des NCC par rapport au paradigme de l'ADN. |
@Article{ian_shal_01,
author = {Jack, Anthony Ian and Shallice, Tim},
title = {Introspective physicalism as an approach to the science of consciousness.},
journal = {Cognition},
year = {2001},
volume = {79},
number = {1-2},
pages = {161-196},
abstract = {Most theories of consciousness are based on vague speculations about the properties of conscious experience. We aim to provide a more solid basis for a science of consciousness. We argue that a theory of consciousness should provide an account of the very processes that allow us to acquire and use information about our own mental states the processes underlying introspection. This can be achieved through the construction of information processing models that can account for Type-C processes. Type-C processes can be specified experimentally by identifying paradigms in which awareness of the stimulus is necessary for an intentional action. The Shallice (1988b) framework is put forward as providing an initial account of Type-C processes, which can relate perceptual consciousness to consciously performed actions. Further, we suggest that this framework may be refined through the investigation of the functions of prefrontal cortex. The formulation of our approach requires us to consider fundamental conceptual and methodological issues associated with consciousness. The most significant of these issues concerns the scientific use of introspective evidence. We outline and justify a conservative methodological approach to the use of introspective evidence, with attention to the difficulties historically associated with its use in psychology.},
comments = {Mise en perspective de la psycho et des recherches sur la conscience, des NCC par rapport au paradigme de l'ADN.},
keywords = {Consciousness, awareness, action, NCC},
url = {http://cogprints.ecs.soton.ac.uk/archive/00001252/00/introspectivephysicalismpreprint.pdf},
rating = {D}
}
-
Kimberly A. Jameson and Susan M. Highnote.
Richer color experience in observers with multiple photopigment opsin genes.
Psychonomics Bulletin & Review,
8(2):244-261,
2001.
Keywords: color,
perception,
genetics,
photopigment.
| Abstract: Traditional color vision theory posits that three types of retinal photopigrnents transduce light into a trivariate neural color code, thereby explaining color-matching behaviors. This principle of trichromacy is in need of reexamination in view of molecular genetics results suggesting that a substantial percentage of women possess more than three classes of retinal photopigrnents. At issue is the question of whether four-photopigrnent retinas necessarily yield trichromatic color perception. In the present paper, we review results and theory underlying the accepted photoreceptor-based model of trichromacy. A review of the psychological literature shows that gender-linked differences in color perception warrant further investigation of retinal photopigrnent classes and color perception relations. We use genetic analyses to examine an important position in the gene sequence, and we empirically assess and compare the color perception of individuals possessing more than three retinal photopigment genes with those possessing fewer retinal photopigrnent genes. Women with four-photopigment genotypes are found to perceive significantly more chromatic appearances in comparison with either male or female trichromat controls. We provide a rationale for this previously undetected finding and discuss implications for theories of color perception and gender differences in color behavior. |
@Article{jame_high_01,
author = {Jameson, Kimberly A. and Highnote, Susan M.},
title = {Richer color experience in observers with multiple photopigment opsin genes},
journal = {Psychonomics Bulletin & Review},
year = {2001},
volume = {8},
number = {2},
pages = {244-261},
abstract = {Traditional color vision theory posits that three types of retinal photopigrnents transduce light into a trivariate neural color code, thereby explaining color-matching behaviors. This principle of trichromacy is in need of reexamination in view of molecular genetics results suggesting that a substantial percentage of women possess more than three classes of retinal photopigrnents. At issue is the question of whether four-photopigrnent retinas necessarily yield trichromatic color perception. In the present paper, we review results and theory underlying the accepted photoreceptor-based model of trichromacy. A review of the psychological literature shows that gender-linked differences in color perception warrant further investigation of retinal photopigrnent classes and color perception relations. We use genetic analyses to examine an important position in the gene sequence, and we empirically assess and compare the color perception of individuals possessing more than three retinal photopigment genes with those possessing fewer retinal photopigrnent genes. Women with four-photopigment genotypes are found to perceive significantly more chromatic appearances in comparison with either male or female trichromat controls. We provide a rationale for this previously undetected finding and discuss implications for theories of color perception and gender differences in color behavior.},
rating = {B},
keywords = {color, perception, genetics, photopigment},
url = {http://aris.ss.uci.edu/cogsci/personnel/kjameson/JHW2001.pdf}
}
-
Laurence T. Maloney.
Illuminant cues in surface color perception: tests of three candidate cues.
Vision Research,
41:2581-2600,
2001.
Keywords: color constancy,
color,
perception.
| Abstract: Many recent computational models of surface color perception presuppose information about illumination in scenes. The models differ primarily in the physical process each makes use of as a cue to the illuminant. We evaluated whether the human visual system makes use of any of three of the following candidate illuminant cues: (1) specular highlight, (2) full surface specularity [Lee, H. C. (1986). Method for computing the scene-illuminant chromaticity from specular highlights. Journal of the Optical Society of America A, 3(10), 1694 1699; D Zmura, M., & Lennie, P. (1986). Mechanisms of color constancy. Journal of the Optical Society of America A, 3(10), 1662 1672], and (3) uniform background. Observers viewed simulated scenes binocularly in a computer-controlled Wheatstone stereoscope. All simulated scenes contained a uniform background plane perpendicular to the observer s line of sight and a small number of specular, colored spheres resting on the uniform background. Scenes were rendered under either standard illuminant D65 or standard illuminant A. Observers adjusted the color of a small, simulated test patch to appear achromatic. In a series of experiments we perturbed the illuminant color signaled by each candidate cue and looked for an influence of the changed cue on achromatic settings. We found that the specular highlight cue had a significant influence, but that the influence was asymmetric: greater when the base illuminant, CIE standard Illuminant A, was perturbed in the direction of Illuminant D65 than vice versa. Neither the full surface specularity cue nor the background cue had any observable influence. The lack of influence of the background cue is likely due to the placement of the test patch in front of the background rather than, as is typical, embedded in the background |
| Comments: on peut sérieusement se demander si le dispositif expérimental, qui ne prend en compte que la position des yeux et par leur orientation, n'évacue pas la cue "full specularity". |
@Article{malo_01,
author = {Maloney, Laurence T.},
title = {Illuminant cues in surface color perception: tests of three candidate cues},
journal = {Vision Research},
year = {2001},
volume = {41},
pages = {2581-2600},
comments = {on peut sérieusement se demander si le dispositif expérimental, qui ne prend en compte que la position des yeux et par leur orientation, n'évacue pas la cue "full specularity". },
rating = {C},
url = {http://www.psych.nyu.edu/maloney/YangMaloney_IllumCues_VisRes2001.pdf},
keywords = {color constancy, color, perception},
abstract = {Many recent computational models of surface color perception presuppose information about illumination in scenes. The models differ primarily in the physical process each makes use of as a cue to the illuminant. We evaluated whether the human visual system makes use of any of three of the following candidate illuminant cues: (1) specular highlight, (2) full surface specularity [Lee, H. C. (1986). Method for computing the scene-illuminant chromaticity from specular highlights. Journal of the Optical Society of America A, 3(10), 1694 1699; D Zmura, M., & Lennie, P. (1986). Mechanisms of color constancy. Journal of the Optical Society of America A, 3(10), 1662 1672], and (3) uniform background. Observers viewed simulated scenes binocularly in a computer-controlled Wheatstone stereoscope. All simulated scenes contained a uniform background plane perpendicular to the observer s line of sight and a small number of specular, colored spheres resting on the uniform background. Scenes were rendered under either standard illuminant D65 or standard illuminant A. Observers adjusted the color of a small, simulated test patch to appear achromatic. In a series of experiments we perturbed the illuminant color signaled by each candidate cue and looked for an influence of the changed cue on achromatic settings. We found that the specular highlight cue had a significant influence, but that the influence was asymmetric: greater when the base illuminant, CIE standard Illuminant A, was perturbed in the direction of Illuminant D65 than vice versa. Neither the full surface specularity cue nor the background cue had any observable influence. The lack of influence of the background cue is likely due to the placement of the test patch in front of the background rather than, as is typical, embedded in the background}
}
-
Erik Myin.
Color and the duplication assumption.
Synthèse,
2001.
Keywords: inverted spectrum,
perception,
philosophy.
| Abstract: Susan Hurley has attacked the `Duplication Assumption', the assumption that creatures with exactly the same internal states could function exactly alike in environments that are systematically distorted. She argues that the dynamical interdependence of action and perception is highly problematic for the Duplication Assumption when it involves spatial states and capacities, whereas no such problems arise when it involves color states and capacities. I will try to establish that the Duplication Assumption makes even less sense for lightness than for some of the spatial cases. This is due not only to motor factors, but to the basic physical asymmetry between black and white. I then argue that the case can be extended from lightness perception to hue perception. Overall, the aims of this paper are: (1) to extend Susan Hurley's critique of the Duplication Assumption; (2) to argue against highly constrained versions of Inverted Spectrum arguments; (3) to propose a broader conception of the vehicle for color perception. |
| Comments: La 'duplication assumption' consiste a inverser le monde et inverser les inputs et outputs proximaux, et prétendre que ça ne changerait rien. Erik critique l'idée sur la base de relations physiques qui ne seraient plus respectées. |
@Article{myin_01,
author = {Myin, Erik},
title = {Color and the duplication assumption},
journal = {Synthèse},
year = {2001},
abstract = {Susan Hurley has attacked the `Duplication Assumption', the assumption that creatures with exactly the same internal states could function exactly alike in environments that are systematically distorted. She argues that the dynamical interdependence of action and perception is highly problematic for the Duplication Assumption when it involves spatial states and capacities, whereas no such problems arise when it involves color states and capacities. I will try to establish that the Duplication Assumption makes even less sense for lightness than for some of the spatial cases. This is due not only to motor factors, but to the basic physical asymmetry between black and white. I then argue that the case can be extended from lightness perception to hue perception. Overall, the aims of this paper are: (1) to extend Susan Hurley's critique of the Duplication Assumption; (2) to argue against highly constrained versions of Inverted Spectrum arguments; (3) to propose a broader conception of the vehicle for color perception.},
comments = {La 'duplication assumption' consiste a inverser le monde et inverser les inputs et outputs proximaux, et prétendre que ça ne changerait rien. Erik critique l'idée sur la base de relations physiques qui ne seraient plus respectées. },
url = {http://www.kluweronline.com/article.asp?PIPS=271325&PDF=1},
rating = {C},
keywords = {inverted spectrum, perception, philosophy}
}
-
J. Kevin O'Regan and Alva Noë.
A sensorimotor account of vision and visual consciousness.
Behavioral and Brain Sciences,
24(5),
2001.
Keywords: philosophy,
psychology,
consciousness,
vision.
| Abstract: Many current neurophysiological, psychophysical and psychological approaches to vision rest on the idea that when we see, the brain produces an internal representation of the world. The activation of this internal representation is assumed to give rise to the experience of seeing. The problem with this kind of approach is that it leaves unexplained how the existence of such a detailed internal representation might produce visual consciousness. An alternative proposal is made here. We propose that seeing is a way of acting. It is a particular way of exploring the environment. Activity in internal representations does not generate the experience of seeing. The outside world serves as its own, external, representation. The experience of seeing occurs when the organism masters what we call the governing laws of sensorimotor contingency. The advantage of this approach is that it provides a natural and principled way of accounting for visual consciousness, and for the differences in the perceived quality of sensory experience in the different sensory modalities. Several lines of empirical evidence are brought forward in support of the theory, in particular: evidence from experiments in sensorimotor adaptation, visual "filling in", visual stability despite eye movements, change blindness, sensory substitution, and color perception. |
@Article{oreg_noe_01,
author = {O'Regan, J. Kevin and No\"{e}, Alva},
title = {A sensorimotor account of vision and visual consciousness},
journal = {Behavioral and Brain Sciences},
volume = {24},
number = {5},
year = {2001},
url = {http://www.bbsonline.org/Preprints/ORegan/},
keywords = {philosophy, psychology, consciousness, vision},
rating = {B},
abstract = {Many current neurophysiological, psychophysical and psychological approaches to vision rest on the idea that when we see, the brain produces an internal representation of the world. The activation of this internal representation is assumed to give rise to the experience of seeing. The problem with this kind of approach is that it leaves unexplained how the existence of such a detailed internal representation might produce visual consciousness. An alternative proposal is made here. We propose that seeing is a way of acting. It is a particular way of exploring the environment. Activity in internal representations does not generate the experience of seeing. The outside world serves as its own, external, representation. The experience of seeing occurs when the organism masters what we call the governing laws of sensorimotor contingency. The advantage of this approach is that it provides a natural and principled way of accounting for visual consciousness, and for the differences in the perceived quality of sensory experience in the different sensory modalities. Several lines of empirical evidence are brought forward in support of the theory, in particular: evidence from experiments in sensorimotor adaptation, visual "filling in", visual stability despite eye movements, change blindness, sensory substitution, and color perception.}
}
-
S. Shimojo and L. Shams.
Sensory modalities are not separate modalities: plasticity and interactions.
Current Opinion in Neurobiology,
11:505-509,
2001.
Keywords: sensation,
modalities,
plasticity,
neuroscience.
| Abstract: Historically, perception has been viewed as a modular function, with the different sensory modalities operating independently of each other. Recent behavioral and brain imaging studies challenge this view, by suggesting that cross-modal interactions are the rule and not the exception in perception, and that the cortical pathways previously thought to be sensory-specific are modulated by signals from other modalities. |
| Comments: Review des différentes preuves du caractère multimodal de la perception. Refs sur les connaissances sur les zones d'intégrations multisensorielles. |
@Article{shim_sham_01,
author = {Shimojo, S. and Shams, L.},
title = {Sensory modalities are not separate modalities: plasticity and interactions},
journal = {Current Opinion in Neurobiology},
year = {2001},
volume = {11},
pages = {505-509},
comments = {Review des différentes preuves du caractère multimodal de la perception. Refs sur les connaissances sur les zones d'intégrations multisensorielles.},
url = {http://neuro.caltech.edu/publications/nbb408.pdf},
keywords = {sensation, modalities, plasticity, neuroscience},
rating = {C},
abstract = {Historically, perception has been viewed as a modular function, with the different sensory modalities operating independently of each other. Recent behavioral and brain imaging studies challenge this view, by suggesting that cross-modal interactions are the rule and not the exception in perception, and that the cortical pathways previously thought to be sensory-specific are modulated by signals from other modalities.}
}
-
Evan Thompson and Francisco J. Varela.
Radical embodiment: neural dynamics and cosnciousness.
TRENDS in Cognitive Sciences,
5(10):418-425,
2001.
Keywords: philosophy,
physiology,
neuroscience,
embodiment,
enaction,
dynamical systems.
| Abstract: Manifeste de la position 'enactive': la conscience n'est pas basé sur les épiphénomènes que sont les NCC, mais sur des interactions dynamiques de grande échelles, avec une causalité montante et descendante vis-à-vis des propriétés émergentes du système. D'autre part, critique de la position internaliste: le système dynamique implique le corps et l'environnement et il n'est pas donné que le decoupage en sous-système ne doivent pas se faire au travers de ces frontières plutot que selon ces frontières. |
@Article{thom_vare_01,
author = {Thompson, Evan and Varela, Francisco J.},
title = {Radical embodiment: neural dynamics and cosnciousness},
journal = {{TRENDS} in Cognitive Sciences},
volume = {5},
number = {10},
year = {2001},
pages = {418-425},
url = {http://www.yorku.ca/evant/Thompson%20&%20Varela.pdf},
abstract = {Manifeste de la position 'enactive': la conscience n'est pas basé sur les épiphénomènes que sont les NCC, mais sur des interactions dynamiques de grande échelles, avec une causalité montante et descendante vis-à-vis des propriétés émergentes du système. D'autre part, critique de la position internaliste: le système dynamique implique le corps et l'environnement et il n'est pas donné que le decoupage en sous-système ne doivent pas se faire au travers de ces frontières plutot que selon ces frontières.},
keywords = {philosophy, physiology, neuroscience, embodiment, enaction, dynamical systems}
}
-
Arne Valberg.
Unique hues: an old problem for a new generation.
Vision Research,
41:1645-1657,
2001.
Keywords: color,
unique hues,
review,
NCC.
| Abstract: The practical success of the classical theories of colour vision, such as that of Young-Helmholtz when applied to the measurement and reproduction of colour stimuli, and that of Hering's in art and architecture, has overshadowed the fact that neither theory achieved its main goal, namely to explain colour qualities. Neither the three types of cone, nor the first opponent stages of neural processing in the retina and the lateral geniculate nucleus can serve as direct correlates to the perception of elementary, or unique colours, such as red, green, yellow and blue. While our subjective experiences of these qualities do not submit to measurement, physiological conditions that are required to perceive colours of a constant hue can be identified. For instance, a constant ratio of responses of different types of opponent cells in the retina and the lateral geniculate nucleus of primates may serve as a neurophysiological correlate of a constant hue. This is, however, not the correlate for seeing a particular hue quality, say unique red. This latter correlate, if it exists as a separable entity, must be associated with yet unidentified, higher-level neural activities. The fundamental problems encountered in relating colour qualities to neural activities are discussed and references are made to the current debate about phenomenal consciousness. |
| Comments: une mini review utile, les pieds dans le plat à propos des NCC |
@Article{valb_01,
author = {Valberg, Arne},
title = {Unique hues: an old problem for a new generation},
journal = {Vision Research},
year = {2001},
volume = {41},
pages = {1645-1657},
comments = {une mini review utile, les pieds dans le plat à propos des NCC},
rating = {C},
url = {http://linkinghub.elsevier.com/retrieve/pii/S0042698901000414},
keywords = {color, unique hues, review, NCC},
abstract = {The practical success of the classical theories of colour vision, such as that of Young-Helmholtz when applied to the measurement and reproduction of colour stimuli, and that of Hering's in art and architecture, has overshadowed the fact that neither theory achieved its main goal, namely to explain colour qualities. Neither the three types of cone, nor the first opponent stages of neural processing in the retina and the lateral geniculate nucleus can serve as direct correlates to the perception of elementary, or unique colours, such as red, green, yellow and blue. While our subjective experiences of these qualities do not submit to measurement, physiological conditions that are required to perceive colours of a constant hue can be identified. For instance, a constant ratio of responses of different types of opponent cells in the retina and the lateral geniculate nucleus of primates may serve as a neurophysiological correlate of a constant hue. This is, however, not the correlate for seeing a particular hue quality, say unique red. This latter correlate, if it exists as a separable entity, must be associated with yet unidentified, higher-level neural activities. The fundamental problems encountered in relating colour qualities to neural activities are discussed and references are made to the current debate about phenomenal consciousness.}
}
-
M. Wexler,
F. Panerai,
I. Lamouret,
and J. Droulez.
Self-motion and the perception of stationary objects.
Nature,
409:85-88,
2001.
Keywords: perception,
movement,
space.
| Comments: La perspective et le mouvement sont deux indices permetant la perception de la profondeur. Si l'on produit des stimulus dans lesquels ces deux indices sont en conflit, on observe une différence entre les observateurs passifs, pour lequels le mouvement du champ visuel est donné, et les observateurs actifs, qui créent par leur propre mouvement les variations du champ visuel. Ces derniers se reposent plus sur l'indice du mouvement, apparemment car cela permet d'ajouter à l'hypothèse de rigidité celle de stationnarité. On peut s'intéroger sur la validité de considérer comme équivalent une expérience binoculaire et le film monoculaire de cette expérience. |
@Article{wexl_pane_lamo_drou_01,
author = {Wexler, M. and Panerai, F. and Lamouret, I. and Droulez, J.},
title = {Self-motion and the perception of stationary objects},
journal = {Nature},
year = {2001},
volume = {409},
pages = {85-88},
rating = {C},
keywords = {perception, movement, space},
comments = {La perspective et le mouvement sont deux indices permetant la perception de la profondeur. Si l'on produit des stimulus dans lesquels ces deux indices sont en conflit, on observe une différence entre les observateurs passifs, pour lequels le mouvement du champ visuel est donné, et les observateurs actifs, qui créent par leur propre mouvement les variations du champ visuel. Ces derniers se reposent plus sur l'indice du mouvement, apparemment car cela permet d'ajouter à l'hypothèse de rigidité celle de stationnarité. On peut s'intéroger sur la validité de considérer comme équivalent une expérience binoculaire et le film monoculaire de cette expérience.},
url = {http://cogprints.ecs.soton.ac.uk/archive/00000950/}
}
-
D. M. Wolpert,
Z. Ghahramani,
and J. R. Flanagan.
Perspectives and Problems in Motor Learning.
TRENDS in Cognitive Sciences,
5(11):487-494,
november 2001.
Keywords: motor control,
physiology.
| Comments: An overview of the motor learning problem. |
@Article{wolp_ghah_flan_01,
author = {Wolpert, D. M. and Ghahramani, Z. and Flanagan, J. R.},
title = {Perspectives and Problems in Motor Learning},
journal = {TRENDS in Cognitive Sciences},
year = {2001},
volume = {5},
number = {11},
pages = {487-494},
month = {november},
comments = {An overview of the motor learning problem.},
url = {http://www.hera.ucl.ac.uk/sml/publications/papers/WolGhaFla01.pdf},
keywords = {motor control, physiology},
rating = {C}
}
-
Eugene Asarin and Ahmed Bouajjani.
Perturbed Turing Machines and Hybrid Systems.
In Logic in Computer Science,
pages 269-278,
2001.
Keywords: computation theory.
| Comments: surtout intéressant pour sa présentation de différents modèles de calcul. |
@inproceedings{ asar_boua_01,
author = {Eugene Asarin and Ahmed Bouajjani},
title = {Perturbed Turing Machines and Hybrid Systems},
booktitle = {Logic in Computer Science},
pages = {269-278},
year = {2001},
url = {citeseer.ist.psu.edu/article/asarin01perturbed.html},
rating = {C},
comments = {surtout intéressant pour sa présentation de différents modèles de calcul.},
keywords = {computation theory}
}
-
Ernst (von) Glasersfled.
Scheme Theory as a key to the learning paradox.
In ,
2001.
Keywords: learning,
philosophy.
| Abstract: Carl Bereiter s article Toward a solution of the learning paradox appeared in 1985, was widely read and cited, but did not end the discussion about the learning paradox . My contribution is an attempt to show that it is in fact a spurious problem and that the paradox springs from unwarranted traditional views of knowledge and conceptualization. A constructivist orientation adopting Peirce s notion of abduction and a particular interpretation of Piaget s scheme theory opens a different and perhaps more promising approach. |
| Comments: Le paradoxe de l'apprentissage: comments peut-on apprendre qqchose qui n'est pas déjà présent à l'esprit ? Collecter des données et inférer, ou construire des données en projetant une interprétation ? Pierce et l'abduction: inventer une règle à partir d'un seul exemple. |
@InProceedings{glas_01,
author = {Glasersfled, Ernst (von)},
year = {2001},
title = {Scheme Theory as a key to the learning paradox},
abstract = {Carl Bereiter s article Toward a solution of the learning paradox appeared in 1985, was widely read and cited, but did not end the discussion about the learning paradox . My contribution is an attempt to show that it is in fact a spurious problem and that the paradox springs from unwarranted traditional views of knowledge and conceptualization. A constructivist orientation adopting Peirce s notion of abduction and a particular interpretation of Piaget s scheme theory opens a different and perhaps more promising approach.},
comments = {Le paradoxe de l'apprentissage: comments peut-on apprendre qqchose qui n'est pas déjà présent à l'esprit ? Collecter des données et inférer, ou construire des données en projetant une interprétation ? Pierce et l'abduction: inventer une règle à partir d'un seul exemple. },
url = {http://www.umass.edu/srri/vonGlasersfeld/onlinePapers/pdf/vonGlasersfeld_258.PDF},
rating = {C},
keywords = {learning, philosophy}
}
-
D. D. Lee and H. S. Seung.
Algorithm for Non-negative Matrix Factorization.
In Adv. in Neural Inform. Proc. Systems,
volume 13,
2001.
Keywords: ingeneering,
decomposition.
| Abstract: Non-negative matrix factorization (NMF) has previously been shown to be a useful decomposition for multivariate data. Two different multiplicative algorithms for NMF are analyzed. They differ only slightly in the multiplicative factor used in the update rules. One algorithm can be shown to minimize the conventional least squares error while the other minimizes the generalized Kullback-Leibler divergence. The monotonic convergence of both algorithms can be proven using an auxiliary function analogous to that used for proving convergence of the Expectation- Maximization algorithm. The algorithms can also be interpreted as diagonally rescaled gradient descent, where the rescaling factor is optimally chosen to ensure convergence. |
@InProceedings{lee_seun_01,
author = {Lee, D. D. and Seung, H. S.},
title = {Algorithm for Non-negative Matrix Factorization},
booktitle = {Adv. in Neural Inform. Proc. Systems},
volume = {13},
year = {2001},
Abstract = {Proof convergence of two non-negative matrix factorization algorithms based on the optimization of two distances on matrices.},
url = {http://hebb.mit.edu/people/seung/papers/nmfconverge.pdf},
keywords = {ingeneering, decomposition},
rating = {C},
abstract = {Non-negative matrix factorization (NMF) has previously been shown to be a useful decomposition for multivariate data. Two different multiplicative algorithms for NMF are analyzed. They differ only slightly in the multiplicative factor used in the update rules. One algorithm can be shown to minimize the conventional least squares error while the other minimizes the generalized Kullback-Leibler divergence. The monotonic convergence of both algorithms can be proven using an auxiliary function analogous to that used for proving convergence of the Expectation- Maximization algorithm. The algorithms can also be interpreted as diagonally rescaled gradient descent, where the rescaling factor is optimally chosen to ensure convergence.},
rating = {C}
}
-
F. Meinecke,
A. Ziehe,
M. Kawanabe,
and K-R Müller.
Assessing Reliability of ICA Projections - a Resampling Approach.
In ICA 2001,
2001.
Keywords: ICA,
statistics,
BSS.
| Abstract: When applying unsupervised learning techniques like ICA or temporal decorrelation for BSS, a key question is whether the discovered projections are reliable. In other words: can we give error bars or can we assess the quality of our separation? We use resampling methods to tackle these questions and show experimentally that our proposed variance estimations are strongly correlated to the separation error. We demonstrate that this reliability estimation can be used to choose an appropriate ICA-model, to enhance signifi- cantly the separation performance, and, most important, to mark the components that can really have a physical meaning. An application to data from an MEG1-experiment underlines the usefulness of our approach. |
| Comments: Resampling methods allow for the empirical estimation of the model variable estimators' variance, and thus test the null hypothesis : the data contains no structure. |
@InProceedings{mein_01,
author = {Meinecke, F. and Ziehe, A. and Kawanabe, M. and Müller, K-R},
title = {Assessing Reliability of ICA Projections - a Resampling Approach},
booktitle = {ICA 2001},
year = {2001},
Abstract = {When applying unsupervised learning techniques like ICA or temporal decorrelation for BSS, a key question is whether the discovered projections are reliable. In other words: can we give error bars or can we assess the quality of our separation? We use resampling methods to tackle these questions and show experimentally that our proposed variance estimations are strongly correlated to the separation error. We demonstrate that this reliability estimation can be used to choose an appropriate ICA-model, to enhance signifi- cantly the separation performance, and, most important, to mark the components that can really have a physical meaning. An application to data from an MEG1-experiment underlines the usefulness of our approach.},
comments = {Resampling methods allow for the empirical estimation of the model variable estimators' variance, and thus test the null hypothesis : the data contains no structure. },
rating = {C},
keywords = {ICA, statistics, BSS},
url = {http://ica2001.ucsd.edu/index_files/pdfs/112-meinecke.pdf}
}
-
Giorgio Metta,
Giulio Sandini,
Lorenzo Natale,
and Francesco Panerai.
Sensorimotor interaction in a developing robot.
In First International Workshop on Epigenetic Robotics,
2001.
| Comments: manifesto pour une vision écologique de l'ontogénèse |
@InProceedings{mett_01,
author = {Metta, Giorgio and Sandini, Giulio and Natale, Lorenzo and Panerai, Francesco},
title = {Sensorimotor interaction in a developing robot},
booktitle = {First International Workshop on Epigenetic Robotics},
year = {2001},
rating = {D},
comments = {manifesto pour une vision écologique de l'ontogénèse}
}
-
R. Vollgraf and K. Obermayer.
Multi Dimensional ICA to Separate Correlated Sources.
In ,
2001.
Keywords: ICA,
statistics,
BSS.
| Comments: In order to fulfill the asumption of stationarity donne by most of ICA algorithms, a first temporal (or spatial) ICA can be processed on small patches, and a second ICA on the inputs stationnarised via the resulting matrix. |
@InProceedings{voll_ober_01,
author = {Vollgraf, R. and Obermayer, K.},
title = {Multi Dimensional ICA to Separate Correlated Sources},
year = {2001},
comments = {In order to fulfill the asumption of stationarity donne by most of ICA algorithms, a first temporal (or spatial) ICA can be processed on small patches, and a second ICA on the inputs stationnarised via the resulting matrix.},
rating = {D},
keywords = {ICA, statistics, BSS},
url = {http://www.nips.cc/NIPS2001/papers/psgz/AA19.ps.gz}
}