-
David J. Chalmers.
Neural Correlates of Consciousness: Empirical and Conceptual Questions,
chapter What is a Neural Correlate of Consciousness?.
Neural Correlates of Consciousness: Empirical and Conceptual Issues.
MIT Press,
2000.
Keywords: philosophy,
neuroscience,
NCC.
| Abstract: The search for neural correlates of consciousness (or NCCs) is arguably the cornerstone in the recent resurgence of the science of consciousness. The search poses many difficult empirical problems, but it seems to be tractable in principle, and some ingenious studies in recent years have led to considerable progress. A number of proposals have been put forward concerning the nature and location of neural correlates of consciousness. A few of these include: |
@inBook{chal_00,
AUTHOR = {Chalmers, David J.},
title = {Neural Correlates of Consciousness: Empirical and Conceptual Questions},
chapter = {What is a Neural Correlate of Consciousness?},
editor = {Thomas Metzinger},
series = {Neural Correlates of Consciousness: Empirical and Conceptual Issues},
YEAR = {2000},
publisher = {MIT Press},
url = {http://www.u.arizona.edu/~chalmers/papers/ncc2.html},
keywords = {philosophy, neuroscience, NCC},
rating = {C},
abstract = {The search for neural correlates of consciousness (or NCCs) is arguably the cornerstone in the recent resurgence of the science of consciousness. The search poses many difficult empirical problems, but it seems to be tractable in principle, and some ingenious studies in recent years have led to considerable progress. A number of proposals have been put forward concerning the nature and location of neural correlates of consciousness. A few of these include:}
}
-
Emilio Bizzi,
Matthew C. Tresch,
Philippe Saltiel,
and Andrea d'Avella.
New perspectives on spinal motor systems.
Nature neuroscience,
1:101-107,
2000.
Keywords: motor control,
neuroscience,
physiology.
| Comments: Une bonne partie de l'adaptation motrice semble se réaliser au niveau de la moelle épinière, bien avant le cortex ou même le cervelet. Le controle de la moelle est stable: l'activation de ses neurones détermine un champ de force sur les pattes qui possède un et un seul attracteur. |
@ARTICLE{bizz_00,
AUTHOR = {Bizzi, Emilio and Tresch, Matthew C. and Saltiel, Philippe and d'Avella, Andrea},
TITLE = {New perspectives on spinal motor systems},
JOURNAL = {Nature neuroscience},
YEAR = {2000},
volume = {1},
number = {},
pages = {101-107},
comments = {Une bonne partie de l'adaptation motrice semble se réaliser au niveau de la moelle épinière, bien avant le cortex ou même le cervelet. Le controle de la moelle est stable: l'activation de ses neurones détermine un champ de force sur les pattes qui possède un et un seul attracteur.},
url = {http://web.mit.edu/bcs/bizzilab/publications/bizzi2000.pdf},
rating = {B},
keywords = {motor control, neuroscience, physiology}
}
-
E. Darcy Burgund and Chad J. Marsolek.
Viewpoint-invariant and viewpoint-dependent object recognition in dissociable neural subsystems.
Psychonomic Bulletin & Review,
7(3):480-489,
2000.
Keywords: objects.
| Abstract: Participants viewed objects in the central visual field and then named either same or different depthorientation views of these objects presented briefly in the left or the right visual field. The differentorientation views contained either the same or a different set of parts and relations. Viewpoint-dependent priming was observed when test views were presented directly to the right hemisphere (RH), but not when test views were presented directly to the left hemisphere (LH). Moreover, this pattern of results did not depend on whether the same or a different set of parts and relations could be recovered from the different-orientation views. Results support the theory that a specific subsystem operates more effectively than an abstract subsystem in the RH and stores objects in a manner that produces viewpointdependent effects, whereas an abstract subsystem operates more effectively than a specific subsystem in the LH and does not store objects in a viewpoint-dependent manner. |
| Comments: Résultats expérimentaux cherchant à déterminer les méchanismes de la reconnaissance des objets indépendamment du point de vue, description invariant ou collection de points de vues. Il y aurait les deux, un dans chaque hémisphère. |
@Article{burg_mars_00,
author = {Burgund, E. Darcy and Marsolek, Chad J.},
title = {Viewpoint-invariant and viewpoint-dependent object recognition in dissociable neural subsystems},
journal = {Psychonomic Bulletin & Review},
year = {2000},
volume = {7},
number = {3},
pages = {480-489},
abstract = {Participants viewed objects in the central visual field and then named either same or different depthorientation views of these objects presented briefly in the left or the right visual field. The differentorientation views contained either the same or a different set of parts and relations. Viewpoint-dependent priming was observed when test views were presented directly to the right hemisphere (RH), but not when test views were presented directly to the left hemisphere (LH). Moreover, this pattern of results did not depend on whether the same or a different set of parts and relations could be recovered from the different-orientation views. Results support the theory that a specific subsystem operates more effectively than an abstract subsystem in the RH and stores objects in a manner that produces viewpointdependent effects, whereas an abstract subsystem operates more effectively than a specific subsystem in the LH and does not store objects in a viewpoint-dependent manner.},
comments = {Résultats expérimentaux cherchant à déterminer les méchanismes de la reconnaissance des objets indépendamment du point de vue, description invariant ou collection de points de vues. Il y aurait les deux, un dans chaque hémisphère.},
keywords = {objects},
rating = {D},
url = {http://vision.psy.mq.edu.au/~darrenb/315refs/burg.marsolek.obj.diss.pdf}
}
-
jacob Feldman.
Minimization of Boolean complexity in human concept learning.
Nature,
407:63-633,
2000.
Keywords: complexity,
logic.
| Abstract: One of the unsolved problems in the field of human concept learning concerns the factors that determine the subjective difÆculty of concepts: why are some concepts psychologically simple and easy to learn, while others seem difÆcult, complex or incoherent? This question was much studied in the 1960s1 but was never answered, and more recent characterizations of concepts as prototypes rather than logical rules2,3 leave it unsolved4±6. Here I investigate this question in the domain of Boolean concepts (categories deÆned by logical rules). A series of experiments measured the subjective difÆculty of a wide range of logical varieties of concepts (41 mathematically distinct types in six families a far wider range than has been tested previously). The data reveal a surprisingly simple empirical `law': the subjective difÆculty of a concept is directly proportional to its Boolean complexity (the length of the shortest logically equivalent propositional formula) that is, to its logical incompressibility. |
| Comments: La difficulté subjective des concepts, contrairement à ce qui a été longtemps proclamé, semble bien prédite par la complxité booleénne des propositions |
@Article{feld_00,
author = {Feldman, jacob},
title = {Minimization of Boolean complexity in human concept learning},
journal = {Nature},
year = {2000},
volume = {407},
pages = {63-633},
url = {http://ruccs.rutgers.edu/~jacob/Papers/feldman_nature.pdf},
keywords = {complexity, logic},
abstract = {One of the unsolved problems in the field of human concept learning concerns the factors that determine the subjective difÆculty of concepts: why are some concepts psychologically simple and easy to learn, while others seem difÆcult, complex or incoherent? This question was much studied in the 1960s1 but was never answered, and more recent characterizations of concepts as prototypes rather than logical rules2,3 leave it unsolved4±6. Here I investigate this question in the domain of Boolean concepts (categories deÆned by logical rules). A series of experiments measured the subjective difÆculty of a wide range of logical varieties of concepts (41 mathematically distinct types in six families a far wider range than has been tested previously). The data reveal a surprisingly simple empirical `law': the subjective difÆculty of a concept is directly proportional to its Boolean complexity (the length of the shortest logically equivalent propositional formula) that is, to its logical incompressibility.},
comments = {La difficulté subjective des concepts, contrairement à ce qui a été longtemps proclamé, semble bien prédite par la complxité booleénne des propositions},
rating = {C}
}
-
Peter Halligan and David Oakley.
Greatest myth of all.
New Scientist,
168(2265):35-39,
2000.
Keywords: consciousness,
self,
free will.
| Abstract: What do you mean when you talk about "yourself"? Leading neuroscientists Peter Halligan and David Oakley are rewriting the rules on consciousness. |
@Article{hall_oakl_00,
author = {Halligan, Peter and Oakley, David},
title = {Greatest myth of all},
journal = {New Scientist},
year = {2000},
volume = {168},
number = {2265},
pages = {35-39},
comments = {},
rating = {C},
url = {http://www.ucl.ac.uk/hypnosis/articles/Halligan2000a.pdf},
keywords = {consciousness, self, free will},
abstract = {What do you mean when you talk about "yourself"? Leading neuroscientists Peter Halligan and David Oakley are rewriting the rules on consciousness.}
}
-
Christof Koch and Idan Segev.
The role of single neurons in information processing.
Nature Neuroscience,
3:1171-1177,
2000.
Keywords: neuroscience,
information theory.
| Abstract: Neurons carry out the many operations that extract meaningful information from sensory receptor arrays at the organism s periphery and translate these into action, imagery and memory. Within today s dominant computational paradigm, these operations, involving synapses, membrane ionic channels and changes in membrane potential, are thought of as steps in an algorithm or as computations. The role of neurons in these computations has evolved conceptually from that of a simple integrator of synaptic inputs until a threshold is reached and an output pulse is initiated, to a much more sophisticated processor with mixed analog-digital logic and highly adaptive synaptic elements. |
| Comments: Review des différentes propriétés des neurones, modèles éléctriques, mise en perspective avec modèles computationnels |
@Article{koch_sege_00,
author = {Koch, Christof and Segev, Idan},
title = {The role of single neurons in information processing},
journal = {Nature Neuroscience},
year = {2000},
volume = {3},
pages = {1171-1177},
keywords = {neuroscience, information theory},
abstract = {Neurons carry out the many operations that extract meaningful information from sensory receptor arrays at the organism s periphery and translate these into action, imagery and memory. Within today s dominant computational paradigm, these operations, involving synapses, membrane ionic channels and changes in membrane potential, are thought of as steps in an algorithm or as computations. The role of neurons in these computations has evolved conceptually from that of a simple integrator of synaptic inputs until a threshold is reached and an output pulse is initiated, to a much more sophisticated processor with mixed analog-digital logic and highly adaptive synaptic elements.},
comments = {Review des différentes propriétés des neurones, modèles éléctriques, mise en perspective avec modèles computationnels},
rating = {B},
url = {http://www.nature.com/neuro/journal/v3/n11s/pdf/nn1100_1171.pdf}
}
-
E. Macaluso,
C.D. Frith,
and J. Driver.
Modulation of human visual cortex by crossmodal spatial attention.
Science,
289:1206-1208,
2000.
Keywords: sensory integration,
space,
psychology.
| Abstract: A sudden touch on one hand can improve vision near that hand, revealing crossmodal links in spatial attention. It is often assumed that such links involve only multimodal neural structures, but unimodal brain areas may also be affected. We tested the effect of simultaneous visuo-tactile stimulation on the activity of the human visual cortex. Tactile stimulation enhanced activity in the visual cortex, but only when it was on the same side as a visual target. Analysis of effective connectivity between brain areas suggests that touch influences unimodal visual cortex via back-projections from multimodal parietal areas. This provides a neural explanation for crossmodal links in spatial attention. |
@Article{maca_frit_driv_00,
author = {Macaluso, E. and Frith, C.D. and Driver, J.},
title = {Modulation of human visual cortex by crossmodal spatial attention},
journal = {Science},
year = {2000},
volume = {289},
pages = {1206-1208},
abstract = {A sudden touch on one hand can improve vision near that hand, revealing crossmodal links in spatial attention. It is often assumed that such links involve only multimodal neural structures, but unimodal brain areas may also be affected. We tested the effect of simultaneous visuo-tactile stimulation on the activity of the human visual cortex. Tactile stimulation enhanced activity in the visual cortex, but only when it was on the same side as a visual target. Analysis of effective connectivity between brain areas suggests that touch influences unimodal visual cortex via back-projections from multimodal parietal areas. This provides a neural explanation for crossmodal links in spatial attention.},
url = {http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?holding=npg&cmd=Retrieve&db=PubMed&list_uids=10947990&dopt=Abstract},
rating = {C},
keywords = {sensory integration, space, psychology}
}
-
K. A. C. Martin.
The Pope and grandmother - a frog's-eye view of theory.
Nature Neuroscience,
3(supp):1169,
2000.
Keywords: philosophy,
neuroscience.
@ARTICLE{mart_00,
AUTHOR = {Martin, K. A. C.},
TITLE = {The Pope and grandmother - a frog's-eye view of theory},
JOURNAL = {Nature Neuroscience},
YEAR = {2000},
volume = {3},
number = {supp},
pages = {1169},
keywords = {philosophy, neuroscience},
rating = {C},
url = {http://www.nature.com/cgi-taf/DynaPage.taf?file=/neuro/journal/v3/n11s/full/nn1100_1169.html}
}
-
A. F. M. J. Matarié and O. C. Jenkins.
Automated Derivation of Primitives for Movement Classification.
International Conference on Humanoid Robotics,
2000.
Keywords: motor control.
| Abstract: We present a new method for representing human movement compactly, in terms of a linear superimposition of simpler movements termed primitives. This method is a part of a larger research project aimed at modeling motor control and imitation using the notion of perceptuo-motor primitives, a basis set of coupled perceptual and motor routines. In our model, the perceptual system is biased by the set of motor behaviors the agent can execute, so it automatically classifies observed movements into its executable repertoire. In this paper, we describe a method for automatically deriving a set of primitives directly from human movement data. We used data from a psychophysical experiment on human imitation to derive a set of primitives, and then used those primitives as a basis for superposition and sequencing to reconstruct the original movements. We performed principal component analysis on segments from these data, resulting in a set of basis vectors. Next we clustered in the space of projections of segments onto the eigenvectors, to obtain a set of frequently used movements. To validate the approach experimentally, we used the movement obtained by expanding the cluster points in terms of the eigenvectors as a sequence of via points to control a humanoid dynamic simulation. We also developed an error metric to measure the effectiveness of the process. |
@Article{mata_jenk_00,
author = {Matarié, A. F. M. J. and Jenkins, O. C.},
title = {Automated Derivation of Primitives for Movement Classification},
journal = {International Conference on Humanoid Robotics},
pages = {},
year = {2000},
organization = {MIT},
url = {http://www-robotics.usc.edu/~afod/mypapers/21j.pdf},
abstract = {We present a new method for representing human movement compactly, in terms of a linear superimposition of simpler movements termed primitives. This method is a part of a larger research project aimed at modeling motor control and imitation using the notion of perceptuo-motor primitives, a basis set of coupled perceptual and motor routines. In our model, the perceptual system is biased by the set of motor behaviors the agent can execute, so it automatically classifies observed movements into its executable repertoire. In this paper, we describe a method for automatically deriving a set of primitives directly from human movement data. We used data from a psychophysical experiment on human imitation to derive a set of primitives, and then used those primitives as a basis for superposition and sequencing to reconstruct the original movements. We performed principal component analysis on segments from these data, resulting in a set of basis vectors. Next we clustered in the space of projections of segments onto the eigenvectors, to obtain a set of frequently used movements. To validate the approach experimentally, we used the movement obtained by expanding the cluster points in terms of the eigenvectors as a sequence of via points to control a humanoid dynamic simulation. We also developed an error metric to measure the effectiveness of the process.},
rating = {C},
keywords = {motor control}
}
-
T. P. Minka.
Automatic Choice of Dimensionality for PCA.
NIPS 2000,
pp 598-604,
2000.
Keywords: PCA,
statistics.
| Abstract: A central issue in principal component analysis PCA is choosing the number of principal components to be retained By interpreting PCA as density estimation this paper shows how to use Bayesian model selection to determine the true dimensionality of the data The resulting estimate is simple to compute yet guaranteed to pick the correct dimensionality given enough data The estimate involves an integral over the Steifel manifold of k frames which is di cult to compute exactly But after choosing an appropriate parameterization and applying Laplace s method an accurate and practical estimator is obtained In simulations it is more accurate than cross validation and other proposed algorithms plus it runs much faster |
| Comments: A Bayesian approach on PCA leads, with appropriate priors on the parameters (mixing matrix, noise's mean and variance), to several kind of dimension estimators. The Laplace estimator turn out to be the most accurate and the faster one. |
@Article{mink_00,
author = {Minka, T. P.},
title = {Automatic Choice of Dimensionality for {PCA}},
journal = {NIPS 2000},
pages = {598-604},
year = {2000},
abstract = {A central issue in principal component analysis PCA is choosing the number of principal components to be retained By interpreting PCA as density estimation this paper shows how to use Bayesian model selection to determine the true dimensionality of the data The resulting estimate is simple to compute yet guaranteed to pick the correct dimensionality given enough data The estimate involves an integral over the Steifel manifold of k frames which is di cult to compute exactly But after choosing an appropriate parameterization and applying Laplace s method an accurate and practical estimator is obtained In simulations it is more accurate than cross validation and other proposed algorithms plus it runs much faster},
comments = {A Bayesian approach on PCA leads, with appropriate priors on the parameters (mixing matrix, noise's mean and variance), to several kind of dimension estimators. The Laplace estimator turn out to be the most accurate and the faster one.},
url = {http://vismod.media.mit.edu/tech-reports/TR-514.pdf},
keywords = {PCA, statistics},
rating = {C}
}
-
F. Nielsen.
Randomized Adaptive Algorithms for Mosaicing Systems.
IEICE Trans. Inf. & Syst.,
E83-D(7),
2000.
Keywords: artificial vision.
| Comments: Pour mosaiquer différentes images obtenues de points de vue inconnus, il faut chercher à coupler, à une transformation donnée près, des paires de points définissant le point de vue. C'est un problème combinatoire lourd dont l'article propose une solution efficace non supervisée. |
@Article{niel_00,
author = {Nielsen, F.},
title = {Randomized Adaptive Algorithms for Mosaicing Systems},
journal = {IEICE Trans. Inf. & Syst.},
year = {2000},
volume = {E83-D},
number = {7},
comments = {Pour mosaiquer différentes images obtenues de points de vue inconnus, il faut chercher à coupler, à une transformation donnée près, des paires de points définissant le point de vue. C'est un problème combinatoire lourd dont l'article propose une solution efficace non supervisée.},
url = {http://www.csl.sony.co.jp/person/nielsen/PT/randomizedmosaicing/randomizedmosaicing.ps},
rating = {C},
keywords = {artificial vision}
}
-
Alva Noë and J. Kevin O'Regan.
Perception, Attention and the Grand Illusion.
Psyche,
6(15),
2000.
Keywords: perception,
attention,
vision.
| Abstract: This paper looks at two puzzles raised by the phenomenon of inattentional blindness. First, how can we see at all if, in order to see, we must first perceptually attend to that which we see? Second, if attention is required for perception, why does it seem to us as if we are perceptually aware of the whole detailed visual field when it is quite clear that we do not attend to all that detail? We offer a general framework for thinking about perception and perceptual consciousness that addresses these questions and we propose, in addition, an informal account of the relation between attention and consciousness. On this view, perceptual awareness is a species of attention. |
@Article{noe_oreg_00,
author = {Noë, Alva and O'Regan, J. Kevin},
title = {Perception, Attention and the Grand Illusion},
journal = {Psyche},
year = {2000},
volume = {6},
number = {15},
url = {http://psyche.cs.monash.edu.au/v6/psyche-6-15-noe.html},
rating = {C},
keywords = {perception, attention, vision},
abstract = {This paper looks at two puzzles raised by the phenomenon of inattentional blindness. First, how can we see at all if, in order to see, we must first perceptually attend to that which we see? Second, if attention is required for perception, why does it seem to us as if we are perceptually aware of the whole detailed visual field when it is quite clear that we do not attend to all that detail? We offer a general framework for thinking about perception and perceptual consciousness that addresses these questions and we propose, in addition, an informal account of the relation between attention and consciousness. On this view, perceptual awareness is a species of attention.}
}
-
Gabriel Robles-De-La-Torre and Vincent Hayward.
Force can overcome object geometry in the perception of shape through active touch.
Nature,
412:445-448,
2000.
Keywords: perception,
haptic,
sensorimotor.
| Abstract: Haptic (touch) perception normally entails an active exploration of object surfaces over time. This is called active touch. When exploring the shape of an object, we experience both geometrical4 and force cues. For example, when sliding a Ænger across a surface with a rigid bump on it, the Ænger moves over the bump while being opposed by a force whose direction and magnitude are related to the slope of the bump5. The steeper the bump, the stronger the resistance. Geometrical and force cues are correlated, but it has been commonly assumed that shape perception relies on object geometry alone. Here we show that regardless of surface geometry, subjects identiÆed and located shape features on the basis of force cues or their correlates. Using paradoxical stimuli, for example combining the force cues of a bump with the geometry of a hole, we found that subjects perceived a bump. Conversely, when combining the force cues of a hole with the geometry of a bump, subjects typically perceived a hole. |
| Comments: La perception de la forme semble se baser autant, si ce n'est plus, sur l'orientation de la force de réaction que sur le parcours géométrique effectif du capteur. |
@Article{robl_hayw_0,
author = {Robles-De-La-Torre, Gabriel and Hayward, Vincent},
title = {Force can overcome object geometry in the perception of shape through active touch},
journal = {Nature},
year = {2000},
volume = {412},
number = {},
pages = {445-448},
abstract = {Haptic (touch) perception normally entails an active exploration of object surfaces over time. This is called active touch. When exploring the shape of an object, we experience both geometrical4 and force cues. For example, when sliding a Ænger across a surface with a rigid bump on it, the Ænger moves over the bump while being opposed by a force whose direction and magnitude are related to the slope of the bump5. The steeper the bump, the stronger the resistance. Geometrical and force cues are correlated, but it has been commonly assumed that shape perception relies on object geometry alone. Here we show that regardless of surface geometry, subjects identiÆed and located shape features on the basis of force cues or their correlates. Using paradoxical stimuli, for example combining the force cues of a bump with the geometry of a hole, we found that subjects perceived a bump. Conversely, when combining the force cues of a hole with the geometry of a bump, subjects typically perceived a hole.},
comments = {La perception de la forme semble se baser autant, si ce n'est plus, sur l'orientation de la force de réaction que sur le parcours géométrique effectif du capteur.},
url = {http://www.roblesdelatorre.com/gabriel/GR-VH-Nature2001.pdf},
rating = {C},
keywords = {perception, haptic, sensorimotor}
}
-
S. T. Roweis and L. K. Saul.
Nonlinear Dimensionality Reduction by Locally Linear Embedding.
Science,
290:2323-2326,
December 2000.
Keywords: geometry,
dimension reduction.
| Abstract: Many areas of science depend on exploratory data analysis and visualization. The need to analyze large amounts of multivariate data raises the fundamental problem of dimensionality reduction: how to discover compact representations of high-dimensional data. Here, we introduce locally linear embedding (LLE), an unsupervised learning algorithm that computes low-dimensional, neighborhood- preserving embeddings of high-dimensional inputs. Unlike clustering methods for local dimensionality reduction, LLE maps its inputs into a single global coordinate system of lower dimensionality, and its optimizations do not involve local minima. By exploiting the local symmetries of linear reconstructions, LLE is able to learn the global structure of nonlinear manifolds, such as those generated by images of faces or documents of text. |
@Article{rowe_saul_00,
author = {Roweis, S. T. and Saul, L. K. },
title = {Nonlinear Dimensionality Reduction by Locally Linear Embedding},
journal = {Science},
volume = {290},
month = {December},
pages = {2323-2326},
year = {2000},
keywords = {geometry, dimension reduction},
rating = {B},
url = {http://lsa.colorado.edu/~simon/LexicalSemantics/RoweisSaul.pdf},
abstract = {Many areas of science depend on exploratory data analysis and visualization. The need to analyze large amounts of multivariate data raises the fundamental problem of dimensionality reduction: how to discover compact representations of high-dimensional data. Here, we introduce locally linear embedding (LLE), an unsupervised learning algorithm that computes low-dimensional, neighborhood- preserving embeddings of high-dimensional inputs. Unlike clustering methods for local dimensionality reduction, LLE maps its inputs into a single global coordinate system of lower dimensionality, and its optimizations do not involve local minima. By exploiting the local symmetries of linear reconstructions, LLE is able to learn the global structure of nonlinear manifolds, such as those generated by images of faces or documents of text.}
}
-
Thomas Schreiber.
Measuring Information Transfer.
Physical review letters,
85(2),
2000.
Keywords: stochastic systems,
physics,
information.
| Abstract: An information theoretic measure is derived that quantifies the statistical coherence between systems evolving in time. The standard time delayed mutual information fails to distinguish information that is actually exchanged from shared information due to common history and input signals. In our new approach, these influences are excluded by appropriate conditioning of transition probabilities. The resulting transfer entropy is able to distinguish effectively driving and responding elements and to detect asymmetry in the interaction of subsystems. |
| Comments: l'idée: mesurer la déviation entre P(x_t|x_(t-1)) et P(x_t|x_(t-1),y_(t-1)). |
@Article{schr_00,
author = {Schreiber, Thomas},
title = {Measuring Information Transfer},
journal = {Physical review letters},
year = {2000},
volume = {85},
number = {2},
keywords = {stochastic systems, physics, information},
rating = {C},
comments = {l'idée: mesurer la déviation entre P(x_t|x_(t-1)) et P(x_t|x_(t-1),y_(t-1)).},
abstract = {An information theoretic measure is derived that quantifies the statistical coherence between systems evolving in time. The standard time delayed mutual information fails to distinguish information that is actually exchanged from shared information due to common history and input signals. In our new approach, these influences are excluded by appropriate conditioning of transition probabilities. The resulting transfer entropy is able to distinguish effectively driving and responding elements and to detect asymmetry in the interaction of subsystems. },
url = {http://arxiv.org/abs/nlin.CD/0001042}
}
-
L. Shams,
Y. Kamitani,
and S. Shimojo.
What you see is what you hear.
Nature,
408:788,
2000.
Keywords: vision,
hearing,
perception.
| Abstract: Traditionally, vision has been considered the dominant modality in our multi-sensory perception of the world. Here we present findings that overturn this established view, by showing that auditory information can change the percept of an unambiguous visual stimulus qualitatively (causing a strong visual illusion). These results indicate that, as with other modalities, our visual percepts are malleable by other modalities. We have discovered a visual illusion which is induced by sound: when a single visual flash is accompanied by multiple auditory beeps, the single flash is incorrectly perceived as multiple flashes. These results were obtained by flashing a uniform white disk (subtending 2° at 5° eccentricity) a variable number of times (spaced 50ms apart) on a black background. |
@Article{sham_kami_shim_00,
author = {Shams, L. and Kamitani, Y. and Shimojo, S.},
title = {What you see is what you hear},
journal = {Nature},
year = {2000},
volume = {408},
pages = {788},
abstract = {Traditionally, vision has been considered the dominant modality in our multi-sensory perception of the world. Here we present findings that overturn this established view, by showing that auditory information can change the percept of an unambiguous visual stimulus qualitatively (causing a strong visual illusion). These results indicate that, as with other modalities, our visual percepts are malleable by other modalities. We have discovered a visual illusion which is induced by sound: when a single visual flash is accompanied by multiple auditory beeps, the single flash is incorrectly perceived as multiple flashes. These results were obtained by flashing a uniform white disk (subtending 2° at 5° eccentricity) a variable number of times (spaced 50ms apart) on a black background.},
url = {http://neuro.caltech.edu/publications/shams_preprint.pdf},
rating = {C},
keywords = {vision, hearing, perception}
}
-
J. Sharma,
A. Angelucci,
and M. Sur.
Induction of visual orientation modules in auditory cortex.
Nature,
404:841-847,
2000.
Keywords: neuroscience,
sensation,
perception.
| Abstract: Modules of neurons sharing a common property are a basic organizational feature of mammalian sensory cortex. Primary visual cortex (V1) is characterized by orientation modules groups of cells that share a preferred stimulus orientation which are organized into a highly ordered orientation map. Here we show that in ferrets in which retinal projections are routed into the auditory pathway, visually responsive neurons in `rewired' primary auditory cortex are also organized into orientation modules. The orientation tuning of neurons within these modules is comparable to the tuning of cells in V1 but the orientation map is less orderly. Horizontal connections in rewired cortex are more patchy and periodic than connections in normal auditory cortex, but less so than connections in V1. These data show that afferent activity has a profound inØuence on diverse components of cortical circuitry, including thalamocortical and local intracortical connections, which are involved in the generation of orientation tuning, and long-range horizontal connections, which are important in creating an orientation map. |
@Article{shar_ange_sur_00,
author = {Sharma, J. and Angelucci, A. and Sur, M.},
title = {Induction of visual orientation modules in auditory cortex},
journal = {Nature},
year = {2000},
volume = {404},
pages = {841-847},
rating = {B},
keywords = {neuroscience, sensation, perception},
url = {http://www.cogsci.msu.edu/foraging.pdf},
abstract = {Modules of neurons sharing a common property are a basic organizational feature of mammalian sensory cortex. Primary visual cortex (V1) is characterized by orientation modules groups of cells that share a preferred stimulus orientation which are organized into a highly ordered orientation map. Here we show that in ferrets in which retinal projections are routed into the auditory pathway, visually responsive neurons in `rewired' primary auditory cortex are also organized into orientation modules. The orientation tuning of neurons within these modules is comparable to the tuning of cells in V1 but the orientation map is less orderly. Horizontal connections in rewired cortex are more patchy and periodic than connections in normal auditory cortex, but less so than connections in V1. These data show that afferent activity has a profound inØuence on diverse components of cortical circuitry, including thalamocortical and local intracortical connections, which are involved in the generation of orientation tuning, and long-range horizontal connections, which are important in creating an orientation map.}
}
-
A. Stockman and Sharpe L.T..
The spectral sensitivities of the middle- and long-wavelength-sensitive cones derived from measurements in observers of known genotype.
Vision Res.,
40(13):1711-37,
2000.
Keywords: color,
photoreceptor,
cone,
neuroscience.
| Abstract: The spectral sensitivities of middle- (M-) and long- (L-) wavelength-sensitive cones have been measured in dichromats of known genotype: M-cone sensitivities in nine protanopes, and L-cone sensitivities in 20 deuteranopes. We have used these dichromat cone spectral sensitivities, along with new luminous efficiency determinations, and existing spectral sensitivity and color matching data from normal trichromats, to derive estimates of the human M- and L-cone spectral sensitivities for 2 and 10 degrees dia. central targets, and an estimate of the photopic luminosity function [V(lambda)] for 2 degrees dia. targets, which we refer to as V(2)*(lambda). These new estimates are consistent with dichromatic and trichromatic spectral sensitivities and color matches. |
@Article{stoc_shar_00,
author = {Stockman, A. and Sharpe L.T.},
title = {The spectral sensitivities of the middle- and long-wavelength-sensitive cones derived from measurements in observers of known genotype},
journal = {Vision Res.},
year = {2000},
volume = {40},
number = {13},
pages = {1711-37},
abstract = {The spectral sensitivities of middle- (M-) and long- (L-) wavelength-sensitive cones have been measured in dichromats of known genotype: M-cone sensitivities in nine protanopes, and L-cone sensitivities in 20 deuteranopes. We have used these dichromat cone spectral sensitivities, along with new luminous efficiency determinations, and existing spectral sensitivity and color matching data from normal trichromats, to derive estimates of the human M- and L-cone spectral sensitivities for 2 and 10 degrees dia. central targets, and an estimate of the photopic luminosity function [V(lambda)] for 2 degrees dia. targets, which we refer to as V(2)*(lambda). These new estimates are consistent with dichromatic and trichromatic spectral sensitivities and color matches.},
keywords = {color, photoreceptor, cone, neuroscience},
rating = {B}
}
-
N. V. Swindale.
Lightning is always seen, thunder always heard.
Current Biology,
10:569-571,
2000.
Keywords: neuroscience,
sensation,
perception,
sensory substitution.
| Comments: Un résumé des enjeux et de l'expérience en elle-même, du recablage des furets. Position neutre entre nativistes et empiristes, conclusion au moins dans le cas visuel/auditif pour le contenu informationel du percept plutot que le substrat neuronal. |
@Article{swind_00,
author = {Swindale, N. V.},
title = {Lightning is always seen, thunder always heard},
journal = {Current Biology},
year = {2000},
volume = {10},
pages = {569-571},
rating = {C},
keywords = {neuroscience, sensation, perception, sensory substitution},
abstract = {},
comments = {Un résumé des enjeux et de l'expérience en elle-même, du recablage des furets. Position neutre entre nativistes et empiristes, conclusion au moins dans le cas visuel/auditif pour le contenu informationel du percept plutot que le substrat neuronal.},
url = {http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=10959832&dopt=Citation}
}
-
J. B. Tenenbaum,
V. de Silva,
and J. C. Langford.
A Global Geometric Framework for Nonlinear Dimensionality Reduction.
Science,
290:2319-2323,
2000.
Keywords: geometry,
dimension reduction.
| Abstract: Scientists working with large volumes of high-dimensional data, such as global climate patterns, stellar spectra, or human gene distributions, regularly confront the problem of dimensionality reduction: finding meaningful low-dimensional structures hidden in their high-dimensional observations. The human brain confronts the same problem in everyday perception, extracting from its high-dimensional sensory inputs 30,000 auditory nerve fibers or 106 optic nerve fibers a manageably small number of perceptually relevant features. Here we describe an approach to solving dimensionality reduction problems that uses easily measured local metric information to learn the underlying global geometry of a data set. Unlike classical techniques such as principal component analysis (PCA) and multidimensional scaling (MDS), our approach is capable of discovering the nonlinear degrees of freedom that underlie complex natural observations, such as human handwriting or images of a face under different viewing conditions. In contrast to previous algorithms for nonlinear dimensionality reduction, ours efficiently computes a globally optimal solution, and, for an important class of data manifolds, is guaranteed to converge asymptotically to the true structure. |
@Article{tene_silv_lang_00,
author = {Tenenbaum, J. B. and de Silva, V. and Langford, J. C.},
title = {A Global Geometric Framework for Nonlinear Dimensionality Reduction},
journal = {Science},
volume = {290},
pages = {2319-2323},
year = {2000},
keywords = {geometry, dimension reduction},
url = {http://web.mit.edu/cocosci/Papers/sci_reprint.pdf},
rating = {B},
abstract = {Scientists working with large volumes of high-dimensional data, such as global climate patterns, stellar spectra, or human gene distributions, regularly confront the problem of dimensionality reduction: finding meaningful low-dimensional structures hidden in their high-dimensional observations. The human brain confronts the same problem in everyday perception, extracting from its high-dimensional sensory inputs 30,000 auditory nerve fibers or 106 optic nerve fibers a manageably small number of perceptually relevant features. Here we describe an approach to solving dimensionality reduction problems that uses easily measured local metric information to learn the underlying global geometry of a data set. Unlike classical techniques such as principal component analysis (PCA) and multidimensional scaling (MDS), our approach is capable of discovering the nonlinear degrees of freedom that underlie complex natural observations, such as human handwriting or images of a face under different viewing conditions. In contrast to previous algorithms for nonlinear dimensionality reduction, ours efficiently computes a globally optimal solution, and, for an important class of data manifolds, is guaranteed to converge asymptotically to the true structure.},
}
-
M.A. Webster,
E. Miyahara,
G. Malkoc,
and V.E. Raker.
Variations in normal color vision. I. Cone-opponent axes.
J Opt Soc Am A Opt Image Sci Vis.,
17(9):1535-1544,
2000.
Keywords: color,
opponent theory.
| Abstract: Early postreceptoral color vision is thought to be organized in terms of two principal axes corresponding to opposing L- and M-cone signals (LvsM) or to S-cone signals opposed by a combination of L- and M-cone signals (SvsLM). These cone-opponent axes are now widely used in studies of color vision, but in most cases the corresponding stimulus variations are defined only theoretically, based on a standard observer. We examined the range and implications of interobserver variations in the cone-opponent axes. We used chromatic adaptation to empirically define the LvsM and SvsLM axes and used both thresholds and color contrast adaptation to determine sensitivity to the axes. We also examined the axis variations implied by individual differences in the color matching data of Stiles and Burch [Opt. Acta 6, 1 (1959)]. The axes estimated for individuals can differ measurably from the nominal standard-observer axes and can influence the interpretation of postreceptoral color organization (e.g., regarding interactions between the two axes). Thus, like luminance sensitivity, individual differences in chromatic sensitivity may be important to consider in studies of the cone-opponent axes. |
@Article{webs_00,
author = {Webster, M.A. and Miyahara, E. and Malkoc, G. and Raker, V.E.},
title = {Variations in normal color vision. I. Cone-opponent axes},
journal = {J Opt Soc Am A Opt Image Sci Vis.},
year = {2000},
volume = {17},
number = {9},
pages = {1535-1544},
abstract = {Early postreceptoral color vision is thought to be organized in terms of two principal axes corresponding to opposing L- and M-cone signals (LvsM) or to S-cone signals opposed by a combination of L- and M-cone signals (SvsLM). These cone-opponent axes are now widely used in studies of color vision, but in most cases the corresponding stimulus variations are defined only theoretically, based on a standard observer. We examined the range and implications of interobserver variations in the cone-opponent axes. We used chromatic adaptation to empirically define the LvsM and SvsLM axes and used both thresholds and color contrast adaptation to determine sensitivity to the axes. We also examined the axis variations implied by individual differences in the color matching data of Stiles and Burch [Opt. Acta 6, 1 (1959)]. The axes estimated for individuals can differ measurably from the nominal standard-observer axes and can influence the interpretation of postreceptoral color organization (e.g., regarding interactions between the two axes). Thus, like luminance sensitivity, individual differences in chromatic sensitivity may be important to consider in studies of the cone-opponent axes.},
keywords = {color, opponent theory},
rating = {C}
}
-
L. von Melschner,
S. L. Pallas,
and M. Sur.
Visual behaviour mediated by retinal projections directed to the auditory pathway.
Nature,
404:871-876,
2000.
Keywords: neuroscience,
sensation,
perception.
| Abstract: An unresolved issue in cortical development concerns the relative contributions of intrinsic and extrinsic factors to the functional specification of different cortical areas1-4. Ferrets in which retinal projections are redirected neonatally to the auditory thalamus5 have visually responsive cells in auditory thalamus and cortex, form a retinotopic map in auditory cortex and have visual receptive field properties in auditory cortex that are typical of cells in visual cortex5-8. Here we report that this cross-modal projection and its representation in auditory cortex can mediate visual behaviour. When light stimuli are presented in the portion of the visual field that is 'seen' only by this projection, 'rewired' ferrets respond as though they perceive the stimuli to be visual rather than auditory. Thus the perceptual modality of a neocortical region is instructed to a significant extent by its extrinsic inputs. In addition, gratings of different spatial frequencies can be discriminated by the rewired pathway, although the grating acuity is lower than that of the normal visual pathway. |
@Article{melc_pall_sur_00,
author = {von Melschner, L. and Pallas, S. L. and Sur, M.},
title = {Visual behaviour mediated by retinal projections directed to the auditory pathway},
journal = {Nature},
year = {2000},
volume = {404},
pages = {871-876},
rating = {B},
keywords = {neuroscience, sensation, perception},
url = {http://www.nature.com/cgi-taf/DynaPage.taf?file=/nature/journal/v404/n6780/full/404871a0_fs.html},
abstract = {An unresolved issue in cortical development concerns the relative contributions of intrinsic and extrinsic factors to the functional specification of different cortical areas1-4. Ferrets in which retinal projections are redirected neonatally to the auditory thalamus5 have visually responsive cells in auditory thalamus and cortex, form a retinotopic map in auditory cortex and have visual receptive field properties in auditory cortex that are typical of cells in visual cortex5-8. Here we report that this cross-modal projection and its representation in auditory cortex can mediate visual behaviour. When light stimuli are presented in the portion of the visual field that is 'seen' only by this projection, 'rewired' ferrets respond as though they perceive the stimuli to be visual rather than auditory. Thus the perceptual modality of a neocortical region is instructed to a significant extent by its extrinsic inputs. In addition, gratings of different spatial frequencies can be discriminated by the rewired pathway, although the grating acuity is lower than that of the normal visual pathway.}
}