Autonomous navigation for intelligent mobile robots has gained significant attention,with a focus on enabling robots to generate reliable policies based on maintenance of spatial memory.In this paper,we propose a lear...Autonomous navigation for intelligent mobile robots has gained significant attention,with a focus on enabling robots to generate reliable policies based on maintenance of spatial memory.In this paper,we propose a learning-based visual navigation pipeline that uses topological maps as memory configurations.We introduce a unique online topology construction approach that fuses odometry pose estimation and perceptual similarity estimation.This tackles the issues of topological node redundancy and incorrect edge connections,which stem from the distribution gap between the spatial and perceptual domains.Furthermore,we propose a differentiable graph extraction structure,the topology multi-factor transformer(TMFT).This structure utilizes graph neural networks to integrate global memory and incorporates a multi-factor attention mechanism to underscore elements closely related to relevant target cues for policy generation.Results from photorealistic simulations on image-goal navigation tasks highlight the superior navigation performance of our proposed pipeline compared to existing memory structures.Comprehensive validation through behavior visualization,interpretability tests,and real-world deployment further underscore the adapt-ability and efficacy of our method.展开更多
目的:探究主观认知下降(subjective cognitive decline,SCD)人群动态自发性脑活动改变,及其与空间导航功能的相关性。方法:招募2020年9月至2023年2月期间在南京大学医学院附属鼓楼医院就诊的SCD人群(SCD组,n=72),以及年龄、性别和教育...目的:探究主观认知下降(subjective cognitive decline,SCD)人群动态自发性脑活动改变,及其与空间导航功能的相关性。方法:招募2020年9月至2023年2月期间在南京大学医学院附属鼓楼医院就诊的SCD人群(SCD组,n=72),以及年龄、性别和教育程度相匹配的正常对照(NC组,n=67),所有被试均接受静息状态功能磁共振成像(resting-state functional magnetic resonance imaging,rs-fMRI)检查、空间导航行为学测试和认知功能评估。利用滑动时间窗口方法分割rs-fMRI时间序列。采用SPSS 26.0软件进行统计分析,比较两组间动态低频振幅(dynamic amplitude of low frequency fluctuation,dALFF)差异,将差异脑区的dALFF值与量表评分、空间导航测试进行相关性分析。结果:与NC组相比,SCD组在右侧楔前叶(0.119±0.021,0.130±0.031)、左侧楔叶(0.143±0.034,0.156±0.032)dALFF变异性减低(t=-3.41,-3.12,P<0.05,FDR校正),在右侧枕中回(0.146±0.023,0.137±0.020)、右侧角回(0.148±0.025,0.139±0.026)dALFF变异性升高(t=4.51,3.36,均P<0.05,FDR校正);SCD组右侧楔前叶dALFF变异性与自我空间导航误差(r=-0.341,P=0.025)、延迟空间导航误差(r=-0.286,P=0.035)及记忆功能(r=-0.332,P=0.009)呈显著负相关,左侧枕中回dALFF变异性与语言功能(r=0.339,P=0.015)、视空间功能(r=0.343,P=0.008)呈显著正相关。结论:右侧楔前叶、左侧枕中回dALFF变异性异常改变可能是SCD人群早期认知减退、空间导航障碍的神经机制,可作为早期识别SCD人群潜在的影像标志物。展开更多
The hippocampus has been extensively implicated in spatial navigation in rodents and more recently in bats.Numerous studies have revealed that various kinds of spatial information are encoded across hippocampal region...The hippocampus has been extensively implicated in spatial navigation in rodents and more recently in bats.Numerous studies have revealed that various kinds of spatial information are encoded across hippocampal regions.In contrast,investigations of spatial behavioral correlates in the primate hippocampus are scarce and have been mostly limited to head-restrained subjects during virtual navigation.However,recent advances made in freely-moving primates suggest marked differences in spatial representations from rodents,albeit some similarities.Here,we review empirical studies examining the neural correlates of spatial navigation in the primate(including human)hippocampus at the levels of local field potentials and single units.The lower frequency theta oscillations are often intermittent.Single neuron responses are highly mixed and task-dependent.We also discuss neuronal selectivity in the eye and head coordinates.Finally,we propose that future studies should focus on investigating both intrinsic and extrinsic population activity and examining spatial coding properties in large-scale hippocampal-neocortical networks across tasks.展开更多
基金supported in part by the National Natural Science Foundation of China (62225309,62073222,U21A20480,62361166632)。
文摘Autonomous navigation for intelligent mobile robots has gained significant attention,with a focus on enabling robots to generate reliable policies based on maintenance of spatial memory.In this paper,we propose a learning-based visual navigation pipeline that uses topological maps as memory configurations.We introduce a unique online topology construction approach that fuses odometry pose estimation and perceptual similarity estimation.This tackles the issues of topological node redundancy and incorrect edge connections,which stem from the distribution gap between the spatial and perceptual domains.Furthermore,we propose a differentiable graph extraction structure,the topology multi-factor transformer(TMFT).This structure utilizes graph neural networks to integrate global memory and incorporates a multi-factor attention mechanism to underscore elements closely related to relevant target cues for policy generation.Results from photorealistic simulations on image-goal navigation tasks highlight the superior navigation performance of our proposed pipeline compared to existing memory structures.Comprehensive validation through behavior visualization,interpretability tests,and real-world deployment further underscore the adapt-ability and efficacy of our method.
文摘目的:探究主观认知下降(subjective cognitive decline,SCD)人群动态自发性脑活动改变,及其与空间导航功能的相关性。方法:招募2020年9月至2023年2月期间在南京大学医学院附属鼓楼医院就诊的SCD人群(SCD组,n=72),以及年龄、性别和教育程度相匹配的正常对照(NC组,n=67),所有被试均接受静息状态功能磁共振成像(resting-state functional magnetic resonance imaging,rs-fMRI)检查、空间导航行为学测试和认知功能评估。利用滑动时间窗口方法分割rs-fMRI时间序列。采用SPSS 26.0软件进行统计分析,比较两组间动态低频振幅(dynamic amplitude of low frequency fluctuation,dALFF)差异,将差异脑区的dALFF值与量表评分、空间导航测试进行相关性分析。结果:与NC组相比,SCD组在右侧楔前叶(0.119±0.021,0.130±0.031)、左侧楔叶(0.143±0.034,0.156±0.032)dALFF变异性减低(t=-3.41,-3.12,P<0.05,FDR校正),在右侧枕中回(0.146±0.023,0.137±0.020)、右侧角回(0.148±0.025,0.139±0.026)dALFF变异性升高(t=4.51,3.36,均P<0.05,FDR校正);SCD组右侧楔前叶dALFF变异性与自我空间导航误差(r=-0.341,P=0.025)、延迟空间导航误差(r=-0.286,P=0.035)及记忆功能(r=-0.332,P=0.009)呈显著负相关,左侧枕中回dALFF变异性与语言功能(r=0.339,P=0.015)、视空间功能(r=0.343,P=0.008)呈显著正相关。结论:右侧楔前叶、左侧枕中回dALFF变异性异常改变可能是SCD人群早期认知减退、空间导航障碍的神经机制,可作为早期识别SCD人群潜在的影像标志物。
基金supported by the National Science and Technology Innovation 2030 Major Program(2022ZD0205000)the Lingang Lab(LG202105-01-08).
文摘The hippocampus has been extensively implicated in spatial navigation in rodents and more recently in bats.Numerous studies have revealed that various kinds of spatial information are encoded across hippocampal regions.In contrast,investigations of spatial behavioral correlates in the primate hippocampus are scarce and have been mostly limited to head-restrained subjects during virtual navigation.However,recent advances made in freely-moving primates suggest marked differences in spatial representations from rodents,albeit some similarities.Here,we review empirical studies examining the neural correlates of spatial navigation in the primate(including human)hippocampus at the levels of local field potentials and single units.The lower frequency theta oscillations are often intermittent.Single neuron responses are highly mixed and task-dependent.We also discuss neuronal selectivity in the eye and head coordinates.Finally,we propose that future studies should focus on investigating both intrinsic and extrinsic population activity and examining spatial coding properties in large-scale hippocampal-neocortical networks across tasks.
