The Experts below are selected from a list of 52965 Experts worldwide ranked by ideXlab platform

Ai Koizumi - One of the best experts on this subject based on the ideXlab platform.

  • threat anticipation in pulvinar and in superficial layers of primary visual cortex v1 evidence from layer specific ultra high field 7t fmri
    eNeuro, 2019
    Co-Authors: Beatrice De Gelder, Ai Koizumi, Minye Zhan, Hiroshi Ban, Ikuhiro Kida, Federico De Martino, Maarten J Vaessen, Kaoru Amano
    Abstract:

    Abstract The Perceptual System gives priority to threat-relevant signals with survival value. In addition to the processing initiated by sensory inputs of threat signals, prioritization of threat signals may also include processes related to threat anticipation. These neural mechanisms remain largely unknown. Using ultra-high-field 7 tesla (7T) fMRI, we show that anticipatory processing takes place in the early stages of visual processing, specifically in the pulvinar and V1. When anticipation of a threat-relevant fearful face target triggered false perception of not-presented target, there was enhanced activity in the pulvinar as well as in the V1 superficial-cortical-depth (layers 1–3). The anticipatory activity was absent in the LGN or higher visual cortical areas (V2–V4). The effect in V1 was specific to the perception of fearful face targets and did not generalize to happy face targets. A preliminary analysis showed that the connectivity between the pulvinar and V1 superficial-cortical-depth was enhanced during false perception of threat, indicating that the pulvinar and V1 may interact in preparation of anticipated threat. The anticipatory processing supported by the pulvinar and V1 may play an important role in non-sensory-input-driven anxiety states.

  • layer specific ultra high field 7t fmri showing that threat anticipation is mediated by the pulvinar input to the superficial layers of primary visual cortex v1
    bioRxiv, 2018
    Co-Authors: Ai Koizumi, Beatrice De Gelder, Minye Zhan, Hiroshi Ban, Ikuhiro Kida, Federico De Martino, Kaoru Amano
    Abstract:

    The Perceptual System gives priority to threat relevant signals with survival value. Its mechanism may not only include the processing initiated in the presence of threat signals but also in the mere anticipation of such signals. Here, we show that the pulvinar modulates activity in the early visual cortex (V1) specifically in threat anticipation. Using ultra high field 7T fMRI, we examined the layer specific interaction between V1 and the pulvinar, while taking advantage of the fact that the directionality of such interaction is anatomically constrained in specific V1 layers. Only in anticipation of a fearful face target, but not of a control happy face target, was false perception of anticipated, yet unpresented, target face accompanied by stronger activity in the V1 superficial cortical depth (layers 1 to 3), which was preceded by pre target onset pulvinar activity. The pulvinar may contribute to the visual processing initiated in the anticipation of threat, and play an important role in anxiety.

Kaoru Amano - One of the best experts on this subject based on the ideXlab platform.

  • threat anticipation in pulvinar and in superficial layers of primary visual cortex v1 evidence from layer specific ultra high field 7t fmri
    eNeuro, 2019
    Co-Authors: Beatrice De Gelder, Ai Koizumi, Minye Zhan, Hiroshi Ban, Ikuhiro Kida, Federico De Martino, Maarten J Vaessen, Kaoru Amano
    Abstract:

    Abstract The Perceptual System gives priority to threat-relevant signals with survival value. In addition to the processing initiated by sensory inputs of threat signals, prioritization of threat signals may also include processes related to threat anticipation. These neural mechanisms remain largely unknown. Using ultra-high-field 7 tesla (7T) fMRI, we show that anticipatory processing takes place in the early stages of visual processing, specifically in the pulvinar and V1. When anticipation of a threat-relevant fearful face target triggered false perception of not-presented target, there was enhanced activity in the pulvinar as well as in the V1 superficial-cortical-depth (layers 1–3). The anticipatory activity was absent in the LGN or higher visual cortical areas (V2–V4). The effect in V1 was specific to the perception of fearful face targets and did not generalize to happy face targets. A preliminary analysis showed that the connectivity between the pulvinar and V1 superficial-cortical-depth was enhanced during false perception of threat, indicating that the pulvinar and V1 may interact in preparation of anticipated threat. The anticipatory processing supported by the pulvinar and V1 may play an important role in non-sensory-input-driven anxiety states.

  • layer specific ultra high field 7t fmri showing that threat anticipation is mediated by the pulvinar input to the superficial layers of primary visual cortex v1
    bioRxiv, 2018
    Co-Authors: Ai Koizumi, Beatrice De Gelder, Minye Zhan, Hiroshi Ban, Ikuhiro Kida, Federico De Martino, Kaoru Amano
    Abstract:

    The Perceptual System gives priority to threat relevant signals with survival value. Its mechanism may not only include the processing initiated in the presence of threat signals but also in the mere anticipation of such signals. Here, we show that the pulvinar modulates activity in the early visual cortex (V1) specifically in threat anticipation. Using ultra high field 7T fMRI, we examined the layer specific interaction between V1 and the pulvinar, while taking advantage of the fact that the directionality of such interaction is anatomically constrained in specific V1 layers. Only in anticipation of a fearful face target, but not of a control happy face target, was false perception of anticipated, yet unpresented, target face accompanied by stronger activity in the V1 superficial cortical depth (layers 1 to 3), which was preceded by pre target onset pulvinar activity. The pulvinar may contribute to the visual processing initiated in the anticipation of threat, and play an important role in anxiety.

Beatrice De Gelder - One of the best experts on this subject based on the ideXlab platform.

  • threat anticipation in pulvinar and in superficial layers of primary visual cortex v1 evidence from layer specific ultra high field 7t fmri
    eNeuro, 2019
    Co-Authors: Beatrice De Gelder, Ai Koizumi, Minye Zhan, Hiroshi Ban, Ikuhiro Kida, Federico De Martino, Maarten J Vaessen, Kaoru Amano
    Abstract:

    Abstract The Perceptual System gives priority to threat-relevant signals with survival value. In addition to the processing initiated by sensory inputs of threat signals, prioritization of threat signals may also include processes related to threat anticipation. These neural mechanisms remain largely unknown. Using ultra-high-field 7 tesla (7T) fMRI, we show that anticipatory processing takes place in the early stages of visual processing, specifically in the pulvinar and V1. When anticipation of a threat-relevant fearful face target triggered false perception of not-presented target, there was enhanced activity in the pulvinar as well as in the V1 superficial-cortical-depth (layers 1–3). The anticipatory activity was absent in the LGN or higher visual cortical areas (V2–V4). The effect in V1 was specific to the perception of fearful face targets and did not generalize to happy face targets. A preliminary analysis showed that the connectivity between the pulvinar and V1 superficial-cortical-depth was enhanced during false perception of threat, indicating that the pulvinar and V1 may interact in preparation of anticipated threat. The anticipatory processing supported by the pulvinar and V1 may play an important role in non-sensory-input-driven anxiety states.

  • layer specific ultra high field 7t fmri showing that threat anticipation is mediated by the pulvinar input to the superficial layers of primary visual cortex v1
    bioRxiv, 2018
    Co-Authors: Ai Koizumi, Beatrice De Gelder, Minye Zhan, Hiroshi Ban, Ikuhiro Kida, Federico De Martino, Kaoru Amano
    Abstract:

    The Perceptual System gives priority to threat relevant signals with survival value. Its mechanism may not only include the processing initiated in the presence of threat signals but also in the mere anticipation of such signals. Here, we show that the pulvinar modulates activity in the early visual cortex (V1) specifically in threat anticipation. Using ultra high field 7T fMRI, we examined the layer specific interaction between V1 and the pulvinar, while taking advantage of the fact that the directionality of such interaction is anatomically constrained in specific V1 layers. Only in anticipation of a fearful face target, but not of a control happy face target, was false perception of anticipated, yet unpresented, target face accompanied by stronger activity in the V1 superficial cortical depth (layers 1 to 3), which was preceded by pre target onset pulvinar activity. The pulvinar may contribute to the visual processing initiated in the anticipation of threat, and play an important role in anxiety.

  • recalibration of temporal order perception by exposure to audio visual asynchrony
    Cognitive Brain Research, 2004
    Co-Authors: Jean Vroomen, Mirjam Keetels, Beatrice De Gelder, Paul Bertelson
    Abstract:

    Abstract The perception of simultaneity between auditory and visual information is of crucial importance for maintaining a coordinated representation of a multisensory event. Here we show that the Perceptual System is able to adaptively recalibrate itself to audio-visual temporal asynchronies. Participants were exposed to a train of sounds and light flashes with a constant time lag ranging from −200 (sound first) to +200 ms (light first). Following this exposure, a temporal order judgement (TOJ) task was performed in which a sound and light were presented with a stimulus onset asynchrony (SOA) chosen from 11 values between −240 and +240 ms. Participants either judged whether the sound or the light was presented first, or whether the sound and light were presented simultaneously or successively. The point of subjective simultaneity (PSS) was, in both cases, shifted in the direction of the exposure lag, indicative of recalibration.

Ernst Dieter Dickmanns - One of the best experts on this subject based on the ideXlab platform.

  • EMS-Vision: A Perceptual System for Autonomous Vehicles
    IEEE Transactions on Intelligent Transportation Systems, 2002
    Co-Authors: Rudolf Gregor, M. Lützeler, K. H. Siedersberger, Martin Pellkofer, Ernst Dieter Dickmanns
    Abstract:

    The paper gives a survey on the new Expectation-based Multifocal\nSaccadic vision (EMS-vision) System for autonomous vehicle guidance\ndeveloped at the Universitat der Bundeswehr Munchen (UBM). EMS-Vision is\nthe third generation dynamic vision System following the 4-D approach.\nIts core element is a new camera arrangement, mounted on a high\nbandwidth pan-tilt head for active gaze control. Central knowledge\nrepresentation and a hierarchical System architecture allow efficient\nactivation and control of behavioral capabilities for perception and\naction. The System has been implemented on commercial off-the-shelf\n(COTS) hardware components in both UBM test vehicles VaMoRs and VaMP\nResults from autonomous turnoff maneuvers, performed on army proving\ngrounds, are discussed

  • ems vision a Perceptual System for autonomous vehicles
    IEEE Intelligent Vehicles Symposium, 2000
    Co-Authors: Rudolf Gregor, M. Lützeler, K. H. Siedersberger, Martin Pellkofer, Ernst Dieter Dickmanns
    Abstract:

    A survey is given of an expectation-based multifocal saccadic vision (EMS-Vision) System. EMS-Vision is the 3rd generation dynamic vision System for road vehicle guidance following the 4D approach. It combines a wide field of view (f.o.v.) nearby (>100/spl deg/, L/sub 0.05/=36 m, peripheral part) with central areas of high resolution: a 3-chip-color-camera with a f.o.v. of 23/spl deg/ (L/sub 0.05/=100 m) and a high sensitivity b/w-camera with a f.o.v. of 5.5/spl deg/ (L/sub 0.05/=300 m, foveal part). At L/sub 0.05/ a single pixel in the image corresponds to 5 cm in the real world. By active gaze control, this foveal cone can be inertially stabilized, be redirected to a point of interest in the wide f.o.v. (saccade), and locked onto a moving object for reducing motion blur (fixation). This vertebrate type of vision System allows new performance levels in machine vision. The System has been implemented on commercial off-the-shelf (COTS) components in test vehicles.

Naoyuki Kubota - One of the best experts on this subject based on the ideXlab platform.

  • Perceptual System using spiking neural network for an intelligent robot
    Systems Man and Cybernetics, 2010
    Co-Authors: Hiroyuki Masuta, Naoyuki Kubota
    Abstract:

    This paper discusses a integrated Perceptual System for intelligent control of a service robot. The robot should be able to perceive the environment flexibly to realize intelligent behavior. We focus on the Perceptual System based on the perceiving-acting cycle discussed in ecological psychology. We propose a Perceptual System composed of the retinal model and the spiking-neural network to realize concept of the perceiving-acting cycle. The proposed method is applied to the robot arm equipped with a 3D-range camera. This proposed method features the robot detects the invariant information of a dish, for example the contrast of a distance Information or a luminance information. As experiments, we discuss about the effectiveness of the proposed method by comparing different input.

  • The perception for partner robot using spiking neural network in dynamic environment
    2008 SICE Annual Conference, 2008
    Co-Authors: Hiroyuki Masuta, Naoyuki Kubota
    Abstract:

    This paper discusses a Perceptual System using spiking neural network for a partner robot from the viewpoint of human visual perception. Recently, various types of robots equip various types of sensors for perceiving the environment. However, the robot is difficult to perceive the necessary information like a human. In this study, we emphasize the importance of human vision for the robot to realize flexible perception. Therefore, we propose a retinal model for a laser range finder, and the information extraction method using a spiking neural network based on perceiving-acting cycle. We apply the proposed method for a human tracking task. As an experimental result, we show the robot can directly perceive the necessary information by the attention mechanism for the flexible perception according to spatiotemporal context based on the spiking neural network.

  • Perceptual control based on prediction for natural communication of a partner robot
    IEEE Transactions on Industrial Electronics, 2007
    Co-Authors: Naoyuki Kubota, Kenichiro Nishida
    Abstract:

    This paper discusses a Perceptual System for natural communication between a partner robot and a human. The prediction is very important to reduce the computational cost and to extract the Perceptual information for the natural communication with a human in the future. First, we propose a prediction-based Perceptual control System based on spiking neurons. The proposed method is composed of four layers, namely: 1) input layer; 2) clustering layer; 3) prediction layer; and 4) Perceptual module selection layer. Next, we propose an unsupervised learning method to perform the clustering of human behavior patterns. Furthermore, the robot selects Perceptual modules used in the next perception according to the predicted Perceptual mode. Furthermore, we show several experimental results of the communication between a partner robot and a human based on our proposed method