The Experts below are selected from a list of 327 Experts worldwide ranked by ideXlab platform
Satoshi Kuroki - One of the best experts on this subject based on the ideXlab platform.
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excitatory neuronal hubs configure multisensory integration of slow waves in Association Cortex
Cell Reports, 2018Co-Authors: Satoshi Kuroki, Takamasa Yoshida, Hidekazu Tsutsui, Mizuho Iwama, Reiko Ando, Takayuki Michikawa, Atsushi Miyawaki, Toshio OhshimaAbstract:Multisensory integration (MSI) is a fundamental emergent property of the mammalian brain. During MSI, perceptual information encoded in patterned activity is processed in multimodal Association Cortex. The systems-level neuronal dynamics that coordinate MSI, however, are unknown. Here, we demonstrate intrinsic hub-like network activity in the Association Cortex that regulates MSI. We engineered calcium reporter mouse lines based on the fluorescence resonance energy transfer sensor yellow cameleon (YC2.60) expressed in excitatory or inhibitory neurons. In medial and parietal Association Cortex, we observed spontaneous slow waves that self-organized into hubs defined by long-range excitatory and local inhibitory circuits. Unlike directional source/sink-like flows in sensory areas, medial/parietal excitatory and inhibitory hubs had net-zero balanced inputs. Remarkably, multisensory stimulation triggered rapid phase-locking mainly of excitatory hub activity persisting for seconds after the stimulus offset. Therefore, Association Cortex tends to form balanced excitatory networks that configure slow-wave phase-locking for MSI. VIDEO ABSTRACT.
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excitatory neuronal hubs configure multisensory integration of slow waves in Association Cortex
Social Science Research Network, 2018Co-Authors: Satoshi Kuroki, Takamasa Yoshida, Hidekazu Tsutsui, Mizuho Iwama, Reiko Ando, Takayuki Michikawa, Atsushi Miyawaki, Toshio OhshimaAbstract:Multisensory integration (MSI) is a fundamental emergent property of the mammalian brain. During MSI, perceptual information encoded in patterned activity is processed in multimodal Association Cortex. The systems-level neuronal dynamics that coordinate MSI, however, are unknown. Here we demonstrate intrinsic hub-like network activity in the Association Cortex that regulates MSI. We engineered novel calcium reporter mouse lines based on the fluorescence resonance energy transfer sensor Yellow Cameleon (YC2.60) expressed in excitatory or inhibitory neurons. In medial and parietal Association Cortex, we observed spontaneous slow waves that self-organized into hubs defined by longrange excitatory and local inhibitory circuits. Unlike directional source/sink flows in sensory areas, medial/parietal excitatory and inhibitory hubs had net zero balanced inputs. Remarkably, multisensory inputs triggered rapid phase-locking mainly of excitatory hub activity persisting for seconds after the stimulus offset. Therefore, Association Cortex has a propensity to form balanced excitatory networks that configure slow-wave phase-locking for MSI.
Toshio Ohshima - One of the best experts on this subject based on the ideXlab platform.
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excitatory neuronal hubs configure multisensory integration of slow waves in Association Cortex
Cell Reports, 2018Co-Authors: Satoshi Kuroki, Takamasa Yoshida, Hidekazu Tsutsui, Mizuho Iwama, Reiko Ando, Takayuki Michikawa, Atsushi Miyawaki, Toshio OhshimaAbstract:Multisensory integration (MSI) is a fundamental emergent property of the mammalian brain. During MSI, perceptual information encoded in patterned activity is processed in multimodal Association Cortex. The systems-level neuronal dynamics that coordinate MSI, however, are unknown. Here, we demonstrate intrinsic hub-like network activity in the Association Cortex that regulates MSI. We engineered calcium reporter mouse lines based on the fluorescence resonance energy transfer sensor yellow cameleon (YC2.60) expressed in excitatory or inhibitory neurons. In medial and parietal Association Cortex, we observed spontaneous slow waves that self-organized into hubs defined by long-range excitatory and local inhibitory circuits. Unlike directional source/sink-like flows in sensory areas, medial/parietal excitatory and inhibitory hubs had net-zero balanced inputs. Remarkably, multisensory stimulation triggered rapid phase-locking mainly of excitatory hub activity persisting for seconds after the stimulus offset. Therefore, Association Cortex tends to form balanced excitatory networks that configure slow-wave phase-locking for MSI. VIDEO ABSTRACT.
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excitatory neuronal hubs configure multisensory integration of slow waves in Association Cortex
Social Science Research Network, 2018Co-Authors: Satoshi Kuroki, Takamasa Yoshida, Hidekazu Tsutsui, Mizuho Iwama, Reiko Ando, Takayuki Michikawa, Atsushi Miyawaki, Toshio OhshimaAbstract:Multisensory integration (MSI) is a fundamental emergent property of the mammalian brain. During MSI, perceptual information encoded in patterned activity is processed in multimodal Association Cortex. The systems-level neuronal dynamics that coordinate MSI, however, are unknown. Here we demonstrate intrinsic hub-like network activity in the Association Cortex that regulates MSI. We engineered novel calcium reporter mouse lines based on the fluorescence resonance energy transfer sensor Yellow Cameleon (YC2.60) expressed in excitatory or inhibitory neurons. In medial and parietal Association Cortex, we observed spontaneous slow waves that self-organized into hubs defined by longrange excitatory and local inhibitory circuits. Unlike directional source/sink flows in sensory areas, medial/parietal excitatory and inhibitory hubs had net zero balanced inputs. Remarkably, multisensory inputs triggered rapid phase-locking mainly of excitatory hub activity persisting for seconds after the stimulus offset. Therefore, Association Cortex has a propensity to form balanced excitatory networks that configure slow-wave phase-locking for MSI.
Hidekazu Tsutsui - One of the best experts on this subject based on the ideXlab platform.
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excitatory neuronal hubs configure multisensory integration of slow waves in Association Cortex
Cell Reports, 2018Co-Authors: Satoshi Kuroki, Takamasa Yoshida, Hidekazu Tsutsui, Mizuho Iwama, Reiko Ando, Takayuki Michikawa, Atsushi Miyawaki, Toshio OhshimaAbstract:Multisensory integration (MSI) is a fundamental emergent property of the mammalian brain. During MSI, perceptual information encoded in patterned activity is processed in multimodal Association Cortex. The systems-level neuronal dynamics that coordinate MSI, however, are unknown. Here, we demonstrate intrinsic hub-like network activity in the Association Cortex that regulates MSI. We engineered calcium reporter mouse lines based on the fluorescence resonance energy transfer sensor yellow cameleon (YC2.60) expressed in excitatory or inhibitory neurons. In medial and parietal Association Cortex, we observed spontaneous slow waves that self-organized into hubs defined by long-range excitatory and local inhibitory circuits. Unlike directional source/sink-like flows in sensory areas, medial/parietal excitatory and inhibitory hubs had net-zero balanced inputs. Remarkably, multisensory stimulation triggered rapid phase-locking mainly of excitatory hub activity persisting for seconds after the stimulus offset. Therefore, Association Cortex tends to form balanced excitatory networks that configure slow-wave phase-locking for MSI. VIDEO ABSTRACT.
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excitatory neuronal hubs configure multisensory integration of slow waves in Association Cortex
Social Science Research Network, 2018Co-Authors: Satoshi Kuroki, Takamasa Yoshida, Hidekazu Tsutsui, Mizuho Iwama, Reiko Ando, Takayuki Michikawa, Atsushi Miyawaki, Toshio OhshimaAbstract:Multisensory integration (MSI) is a fundamental emergent property of the mammalian brain. During MSI, perceptual information encoded in patterned activity is processed in multimodal Association Cortex. The systems-level neuronal dynamics that coordinate MSI, however, are unknown. Here we demonstrate intrinsic hub-like network activity in the Association Cortex that regulates MSI. We engineered novel calcium reporter mouse lines based on the fluorescence resonance energy transfer sensor Yellow Cameleon (YC2.60) expressed in excitatory or inhibitory neurons. In medial and parietal Association Cortex, we observed spontaneous slow waves that self-organized into hubs defined by longrange excitatory and local inhibitory circuits. Unlike directional source/sink flows in sensory areas, medial/parietal excitatory and inhibitory hubs had net zero balanced inputs. Remarkably, multisensory inputs triggered rapid phase-locking mainly of excitatory hub activity persisting for seconds after the stimulus offset. Therefore, Association Cortex has a propensity to form balanced excitatory networks that configure slow-wave phase-locking for MSI.
Jacob Paul - One of the best experts on this subject based on the ideXlab platform.
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a network of topographic maps in human Association Cortex hierarchically transforms visual timing selective responses
Social Science Research Network, 2019Co-Authors: Ben M. Harvey, Serge O. Dumoulin, Alessio Fracasso, Jacob PaulAbstract:Accurately timing sub-second sensory events is crucial when perceiving our dynamic world. This ability allows complex human behaviors that require timing-dependent multisensory integration and action planning. Such behaviors include perception and performance of speech, music, driving and many sports. How are responses to sensory event timing processed for multisensory integration and action planning? We measured responses to viewing systematically changing visual event timing using ultra-high field fMRI. We analyzed these responses with neural population response models selective for event duration and rate, following behavioral, computational and macaque action planning results, and comparisons to alternative models. We found systematic local changes in timing preferences (recently described in supplementary motor area) in an extensive network of topographic timing maps, mirroring sensory cortices and other quantity processing networks. These timing maps were partially left-lateralized and widely spread, from occipital visual areas through parietal multisensory areas to frontal action planning areas. Responses to event duration and rate were closely linked. As in sensory cortical maps, response precision varied systematically with timing preferences and timing selectivity systematically varied between maps. Progressing from posterior to anterior maps, responses to multiple events were increasingly integrated, response selectivity narrowed, and responses focused increasingly on the middle of the presented timing range. These timing maps largely overlap with numerosity map and visual field map networks. In both visual timing map and visual field map networks, selective responses and topographic map organization may facilitate hierarchical transformations by allowing neural populations to interact over minimal distances.
Adam Gazzaley - One of the best experts on this subject based on the ideXlab platform.
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causal role of the prefrontal Cortex in top down modulation of visual processing and working memory
Nature Neuroscience, 2011Co-Authors: Theodore P Zanto, Michael T Rubens, Arul Thangavel, Adam GazzaleyAbstract:This study uses a combination of TMS, fMRI and EEG to provide causal evidence for the role of the prefrontal Cortex in the modulation of selective attention. Participants with greater decrement in visual Association Cortex modulation when TMS was used to knock out the prefrontal contribution had greater working memory performance decline.
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functional interactions between prefrontal and visual Association Cortex contribute to top down modulation of visual processing
Cerebral Cortex, 2007Co-Authors: Adam Gazzaley, Jesse Rissman, Jeffrey W Cooney, Aaron M Rutman, Tyler M Seibert, Wesley C Clapp, Mark DespositoAbstract:Attention-dependent modulation of neural activity in visual Association Cortex (VAC) is thought to depend on top-down modulatory control signals emanating from the prefrontal Cortex (PFC). In a previous functional magnetic resonance imaging study utilizing a working memory task, we demonstrated that activity levels in scene-selective VAC (ssVAC) regions can be enhanced above or suppressed below a passive viewing baseline level depending on whether scene stimuli were attended or ignored (Gazzaley, Cooney, McEvoy, et al. 2005). Here, we use functional connectivity analysis to identify possible sources of these modulatory influences by examining how network interactions with VAC are influenced by attentional goals at the time of encoding. Our findings reveal a network of regions that exhibit strong positive correlations with a ssVAC seed during all task conditions, including foci in the left middle frontal gyrus (MFG). This PFC region is more correlated with the VAC seed when scenes were remembered and less correlated when scenes were ignored, relative to passive viewing. Moreover, the strength of MFG-VAC coupling correlates with the magnitude of attentional enhancement and suppression of VAC activity. Although our correlation analyses do not permit assessment of directionality, these findings suggest that PFC biases activity levels in VAC by adjusting the strength of functional coupling in accordance with stimulus relevance. Language: en
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reward modulation of prefrontal and visual Association Cortex during an incentive working memory task
Brain Research, 2007Co-Authors: Daniel C Krawczyk, Adam Gazzaley, Mark DespositoAbstract:Cognitive performance differs with motivation, but little direct evidence exists regarding the neural mechanisms of the influence of reward motivation on working memory (WM). We tested the effects of motivation on the top-down control in visual WM. Encoding relevant stimuli for maintenance, while suppressing inappropriate inputs is considered a core process in cognition. Prior functional magnetic resonance imaging (fMRI) results demonstrated that stimulus-specific visual Association Cortex serves as a marker of activation differences for task-relevant and task-irrelevant inputs, such that enhanced activity occurs when attention is directed to relevant stimuli and suppressed activity occurs when attention is directed away from irrelevant stimuli [Gazzaley, A., Cooney, J., McEvoy, K., Knight, R.T., and D'Esposito, M. J. Cogn. Neurosci. 17, 507-517]. We used fMRI to test whether differential WM performance, indexed by lowered response times on a delayed-recognition task, was associated with amplification of enhancement and suppression effects during stimulus encoding within visual Association Cortex. Our results indicate that enhancement and suppression are amplified for trials with the highest reward level relative to non-rewarded trials for a scene-selective cortical region. In a face-selective region, similar modulation of enhancement for the highest reward level relative to non-rewarded trials was found. Prefrontal Cortex also showed enhanced activity during high reward trials. Overall these results reveal that reward motivation can play a pivotal role in driving performance through top-down signaling in frontal regions involved in WM, as well as visual Association regions selective to processing the perceptual inputs of the items to be remembered.
