The Experts below are selected from a list of 267 Experts worldwide ranked by ideXlab platform
Philippe G. Schyns - One of the best experts on this subject based on the ideXlab platform.
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dynamic construction of reduced representations in the brain for perceptual Decision Behavior
Current Biology, 2019Co-Authors: Jiayu Zhan, Robin A. A. Ince, Nicola Van Rijsbergen, Philippe G. SchynsAbstract:Summary Over the past decade, extensive studies of the brain regions that support face, object, and scene recognition suggest that these regions have a hierarchically organized architecture that spans the occipital and temporal lobes [ 1 , 2 , 3 , 4 , 5 , 6 , 7 , 8 , 9 , 10 , 11 , 12 , 13 , 14 ], where visual categorizations unfold over the first 250 ms of processing [ 15 , 16 , 17 , 18 , 19 ]. This same architecture is flexibly involved in multiple tasks that require task-specific representations—e.g. categorizing the same object as “a car” or “a Porsche.” While we partly understand where and when these categorizations happen in the occipito-ventral pathway, the next challenge is to unravel how these categorizations happen. That is, how does high-dimensional input collapse in the occipito-ventral pathway to become low dimensional representations that guide Behavior? To address this, we investigated what information the brain processes in a visual perception task and visualized the dynamic representation of this information in brain activity. To do so, we developed stimulus information representation (SIR), an information theoretic framework, to tease apart stimulus information that supports Behavior from that which does not. We then tracked the dynamic representations of both in magneto-encephalographic (MEG) activity. Using SIR, we demonstrate that a rapid (∼170 ms) reduction of Behaviorally irrelevant information occurs in the occipital cortex and that representations of the information that supports distinct Behaviors are constructed in the right fusiform gyrus (rFG). Our results thus highlight how SIR can be used to investigate the component processes of the brain by considering interactions between three variables (stimulus information, brain activity, Behavior), rather than just two, as is the current norm.
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Dynamic Construction of Reduced Representations in the Brain for Perceptual Decision Behavior
2018Co-Authors: Jiayu Zhan, Robin A. A. Ince, Nicola Van Rijsbergen, Philippe G. SchynsAbstract:Current models propose that the brain uses a multi-layered architecture to reduce the high dimensional visual input to lower dimensional representations that support face, object and scene categorizations. However, understanding the brain mechanisms that support such information reduction for Behavior remains challenging. We addressed the challenge using a novel information theoretic framework that quantifies the relationships between three key variables: single-trial information randomly sampled from an ambiguous scene, source-space MEG responses and perceptual Decision Behaviors. In each observer, Behavioral analysis revealed the scene features that subtend their Decisions. Independent source space analyses revealed the flow of these and other features in cortical activity. We show where (at the junction between occipital cortex and ventral regions), when (up until 170 ms post stimulus) and how (by separating task-relevant and irrelevant features) brain regions reduce the high-dimensional scene to construct task-relevant feature representations in the right fusiform gyrus that support Decisions. Our results inform the occipito-temporal pathway mechanisms that reduce and select information to produce Behavior.
Jiayu Zhan - One of the best experts on this subject based on the ideXlab platform.
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dynamic construction of reduced representations in the brain for perceptual Decision Behavior
Current Biology, 2019Co-Authors: Jiayu Zhan, Robin A. A. Ince, Nicola Van Rijsbergen, Philippe G. SchynsAbstract:Summary Over the past decade, extensive studies of the brain regions that support face, object, and scene recognition suggest that these regions have a hierarchically organized architecture that spans the occipital and temporal lobes [ 1 , 2 , 3 , 4 , 5 , 6 , 7 , 8 , 9 , 10 , 11 , 12 , 13 , 14 ], where visual categorizations unfold over the first 250 ms of processing [ 15 , 16 , 17 , 18 , 19 ]. This same architecture is flexibly involved in multiple tasks that require task-specific representations—e.g. categorizing the same object as “a car” or “a Porsche.” While we partly understand where and when these categorizations happen in the occipito-ventral pathway, the next challenge is to unravel how these categorizations happen. That is, how does high-dimensional input collapse in the occipito-ventral pathway to become low dimensional representations that guide Behavior? To address this, we investigated what information the brain processes in a visual perception task and visualized the dynamic representation of this information in brain activity. To do so, we developed stimulus information representation (SIR), an information theoretic framework, to tease apart stimulus information that supports Behavior from that which does not. We then tracked the dynamic representations of both in magneto-encephalographic (MEG) activity. Using SIR, we demonstrate that a rapid (∼170 ms) reduction of Behaviorally irrelevant information occurs in the occipital cortex and that representations of the information that supports distinct Behaviors are constructed in the right fusiform gyrus (rFG). Our results thus highlight how SIR can be used to investigate the component processes of the brain by considering interactions between three variables (stimulus information, brain activity, Behavior), rather than just two, as is the current norm.
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Dynamic Construction of Reduced Representations in the Brain for Perceptual Decision Behavior
2018Co-Authors: Jiayu Zhan, Robin A. A. Ince, Nicola Van Rijsbergen, Philippe G. SchynsAbstract:Current models propose that the brain uses a multi-layered architecture to reduce the high dimensional visual input to lower dimensional representations that support face, object and scene categorizations. However, understanding the brain mechanisms that support such information reduction for Behavior remains challenging. We addressed the challenge using a novel information theoretic framework that quantifies the relationships between three key variables: single-trial information randomly sampled from an ambiguous scene, source-space MEG responses and perceptual Decision Behaviors. In each observer, Behavioral analysis revealed the scene features that subtend their Decisions. Independent source space analyses revealed the flow of these and other features in cortical activity. We show where (at the junction between occipital cortex and ventral regions), when (up until 170 ms post stimulus) and how (by separating task-relevant and irrelevant features) brain regions reduce the high-dimensional scene to construct task-relevant feature representations in the right fusiform gyrus that support Decisions. Our results inform the occipito-temporal pathway mechanisms that reduce and select information to produce Behavior.
Robin A. A. Ince - One of the best experts on this subject based on the ideXlab platform.
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dynamic construction of reduced representations in the brain for perceptual Decision Behavior
Current Biology, 2019Co-Authors: Jiayu Zhan, Robin A. A. Ince, Nicola Van Rijsbergen, Philippe G. SchynsAbstract:Summary Over the past decade, extensive studies of the brain regions that support face, object, and scene recognition suggest that these regions have a hierarchically organized architecture that spans the occipital and temporal lobes [ 1 , 2 , 3 , 4 , 5 , 6 , 7 , 8 , 9 , 10 , 11 , 12 , 13 , 14 ], where visual categorizations unfold over the first 250 ms of processing [ 15 , 16 , 17 , 18 , 19 ]. This same architecture is flexibly involved in multiple tasks that require task-specific representations—e.g. categorizing the same object as “a car” or “a Porsche.” While we partly understand where and when these categorizations happen in the occipito-ventral pathway, the next challenge is to unravel how these categorizations happen. That is, how does high-dimensional input collapse in the occipito-ventral pathway to become low dimensional representations that guide Behavior? To address this, we investigated what information the brain processes in a visual perception task and visualized the dynamic representation of this information in brain activity. To do so, we developed stimulus information representation (SIR), an information theoretic framework, to tease apart stimulus information that supports Behavior from that which does not. We then tracked the dynamic representations of both in magneto-encephalographic (MEG) activity. Using SIR, we demonstrate that a rapid (∼170 ms) reduction of Behaviorally irrelevant information occurs in the occipital cortex and that representations of the information that supports distinct Behaviors are constructed in the right fusiform gyrus (rFG). Our results thus highlight how SIR can be used to investigate the component processes of the brain by considering interactions between three variables (stimulus information, brain activity, Behavior), rather than just two, as is the current norm.
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Dynamic Construction of Reduced Representations in the Brain for Perceptual Decision Behavior
2018Co-Authors: Jiayu Zhan, Robin A. A. Ince, Nicola Van Rijsbergen, Philippe G. SchynsAbstract:Current models propose that the brain uses a multi-layered architecture to reduce the high dimensional visual input to lower dimensional representations that support face, object and scene categorizations. However, understanding the brain mechanisms that support such information reduction for Behavior remains challenging. We addressed the challenge using a novel information theoretic framework that quantifies the relationships between three key variables: single-trial information randomly sampled from an ambiguous scene, source-space MEG responses and perceptual Decision Behaviors. In each observer, Behavioral analysis revealed the scene features that subtend their Decisions. Independent source space analyses revealed the flow of these and other features in cortical activity. We show where (at the junction between occipital cortex and ventral regions), when (up until 170 ms post stimulus) and how (by separating task-relevant and irrelevant features) brain regions reduce the high-dimensional scene to construct task-relevant feature representations in the right fusiform gyrus that support Decisions. Our results inform the occipito-temporal pathway mechanisms that reduce and select information to produce Behavior.
Nicola Van Rijsbergen - One of the best experts on this subject based on the ideXlab platform.
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dynamic construction of reduced representations in the brain for perceptual Decision Behavior
Current Biology, 2019Co-Authors: Jiayu Zhan, Robin A. A. Ince, Nicola Van Rijsbergen, Philippe G. SchynsAbstract:Summary Over the past decade, extensive studies of the brain regions that support face, object, and scene recognition suggest that these regions have a hierarchically organized architecture that spans the occipital and temporal lobes [ 1 , 2 , 3 , 4 , 5 , 6 , 7 , 8 , 9 , 10 , 11 , 12 , 13 , 14 ], where visual categorizations unfold over the first 250 ms of processing [ 15 , 16 , 17 , 18 , 19 ]. This same architecture is flexibly involved in multiple tasks that require task-specific representations—e.g. categorizing the same object as “a car” or “a Porsche.” While we partly understand where and when these categorizations happen in the occipito-ventral pathway, the next challenge is to unravel how these categorizations happen. That is, how does high-dimensional input collapse in the occipito-ventral pathway to become low dimensional representations that guide Behavior? To address this, we investigated what information the brain processes in a visual perception task and visualized the dynamic representation of this information in brain activity. To do so, we developed stimulus information representation (SIR), an information theoretic framework, to tease apart stimulus information that supports Behavior from that which does not. We then tracked the dynamic representations of both in magneto-encephalographic (MEG) activity. Using SIR, we demonstrate that a rapid (∼170 ms) reduction of Behaviorally irrelevant information occurs in the occipital cortex and that representations of the information that supports distinct Behaviors are constructed in the right fusiform gyrus (rFG). Our results thus highlight how SIR can be used to investigate the component processes of the brain by considering interactions between three variables (stimulus information, brain activity, Behavior), rather than just two, as is the current norm.
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Dynamic Construction of Reduced Representations in the Brain for Perceptual Decision Behavior
2018Co-Authors: Jiayu Zhan, Robin A. A. Ince, Nicola Van Rijsbergen, Philippe G. SchynsAbstract:Current models propose that the brain uses a multi-layered architecture to reduce the high dimensional visual input to lower dimensional representations that support face, object and scene categorizations. However, understanding the brain mechanisms that support such information reduction for Behavior remains challenging. We addressed the challenge using a novel information theoretic framework that quantifies the relationships between three key variables: single-trial information randomly sampled from an ambiguous scene, source-space MEG responses and perceptual Decision Behaviors. In each observer, Behavioral analysis revealed the scene features that subtend their Decisions. Independent source space analyses revealed the flow of these and other features in cortical activity. We show where (at the junction between occipital cortex and ventral regions), when (up until 170 ms post stimulus) and how (by separating task-relevant and irrelevant features) brain regions reduce the high-dimensional scene to construct task-relevant feature representations in the right fusiform gyrus that support Decisions. Our results inform the occipito-temporal pathway mechanisms that reduce and select information to produce Behavior.
Jochen Ditterich - One of the best experts on this subject based on the ideXlab platform.
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a comparison between mechanisms of multi alternative perceptual Decision making ability to explain human Behavior predictions for neurophysiology and relationship with Decision theory
Frontiers in Neuroscience, 2010Co-Authors: Jochen DitterichAbstract:While there seems to be relatively wide agreement about perceptual Decision making relying on integration-to-threshold mechanisms, proposed models differ in a variety of details. This study compares a range of mechanisms for multi-alternative perceptual Decision making, including integration with and without leakage, feedforward and feedback inhibition for mediating the competition between integrators, as well as linear and nonlinear mechanisms for combining signals across alternatives. It is shown that a number of mechanisms make very similar predictions for the Decision Behavior and are therefore able to explain previously published data from a multi-alternative perceptual Decision task. However, it is also demonstrated that the mechanisms differ in their internal dynamics and therefore make different predictions for neuorphysiological experiments. The study further addresses the relationship of these mechanisms with Decision theory and statistical testing and analyzes their optimality.
