The Experts below are selected from a list of 360 Experts worldwide ranked by ideXlab platform
Chantal E. Stern - One of the best experts on this subject based on the ideXlab platform.
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resting state connectivity between medial temporal lobe regions and intrinsic cortical networks predicts performance in a Path Integration task
Frontiers in Human Neuroscience, 2018Co-Authors: Sarah C Izen, Chantal E. Stern, Elizabeth R. ChrastilAbstract:Humans differ in their individual navigational performance, in part because successful navigation relies on several diverse abilities. One such navigational capability is Path Integration, the updating of position and orientation during movement, typically in a sparse, landmark-free environment. This study examined the relationship between Path Integration abilities and functional connectivity to several canonical intrinsic brain networks. Intrinsic networks within the brain reflect past inputs and communication as well as structural architecture. Individual differences in intrinsic connectivity have been observed for common networks, suggesting that these networks can inform our understanding of individual spatial abilities. Here, we examined individual differences in intrinsic connectivity using resting state magnetic resonance imaging (rsMRI). We tested Path Integration ability using a loop closure task, in which participants viewed a single video of movement in a circle trajectory in a sparse environment, and then indicated whether the video ended in the same location in which it started. To examine intrinsic brain networks, participants underwent a resting state scan. We found that better performance in the loop task was associated with increased connectivity during rest between the central executive network (CEN) and posterior hippocampus, parahippocampal cortex (PHC) and entorhinal cortex. We also found that connectivity between PHC and the default mode network (DMN) during rest was associated with better loop closure performance. The results indicate that interactions between medial temporal lobe (MTL) regions and intrinsic networks that involve prefrontal cortex (PFC) are important for Path Integration and navigation.
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individual differences in human Path Integration abilities correlate with gray matter volume in retrosplenial cortex hippocampus and medial prefrontal cortex
eNeuro, 2017Co-Authors: Elizabeth R. Chrastil, Michael E. Hasselmo, Chantal E. Stern, Katherine R. Sherrill, Irem AselciogluAbstract:Humans differ in their individual navigational abilities. These individual differences may exist in part because successful navigation relies on several disparate abilities, which rely on different brain structures. One such navigational capability is Path Integration, the updating of position and orientation, in which navigators track distances, directions, and locations in space during movement. Although structural differences related to landmark-based navigation have been examined, gray matter volume related to Path Integration ability has not yet been tested. Here, we examined individual differences in two Path Integration paradigms: (1) a location tracking task and (2) a task tracking translational and rotational self-motion. Using voxel-based morphometry, we related differences in performance in these Path Integration tasks to variation in brain morphology in 26 healthy young adults. Performance in the location tracking task positively correlated with individual differences in gray matter volume in three areas critical for Path Integration: the hippocampus, the retrosplenial cortex, and the medial prefrontal cortex. These regions are consistent with the Path Integration system known from computational and animal models and provide novel evidence that morphological variability in retrosplenial and medial prefrontal cortices underlies individual differences in human Path Integration ability. The results for tracking rotational self-motion-but not translation or location-demonstrated that cerebellum gray matter volume correlated with individual performance. Our findings also suggest that these three aspects of Path Integration are largely independent. Together, the results of this study provide a link between individual abilities and the functional correlates, computational models, and animal models of Path Integration.
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which way and how far tracking of translation and rotation information for human Path Integration
Human Brain Mapping, 2016Co-Authors: Michael E. Hasselmo, Chantal E. Stern, Elizabeth R. Chrastil, Katherine R. SherrillAbstract:Path Integration, the constant updating of the navigator's knowledge of position and orientation during movement, requires both visuospatial knowledge and memory. This study aimed to develop a systems-level understanding of human Path Integration by examining the basic building blocks of Path Integration in humans. To achieve this goal, we used functional imaging to examine the neural mechanisms that support the tracking and memory of translational and rotational components of human Path Integration. Critically, and in contrast to previous studies, we examined movement in translation and rotation tasks with no defined end-point or goal. Navigators accumulated translational and rotational information during virtual self-motion. Activity in hippocampus, retrosplenial cortex (RSC), and parahippocampal cortex (PHC) increased during both translation and rotation encoding, suggesting that these regions track self-motion information during Path Integration. These results address current questions regarding distance coding in the human brain. By implementing a modified delayed match to sample paradigm, we also examined the encoding and maintenance of Path Integration signals in working memory. Hippocampus, PHC, and RSC were recruited during successful encoding and maintenance of Path Integration information, with RSC selective for tasks that required processing heading rotation changes. These data indicate distinct working memory mechanisms for translation and rotation, which are essential for updating neural representations of current location. The results provide evidence that hippocampus, PHC, and RSC flexibly track task-relevant translation and rotation signals for Path Integration and could form the hub of a more distributed network supporting spatial navigation. Hum Brain Mapp 37:3636-3655, 2016. © 2016 Wiley Periodicals, Inc.
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There and Back Again: Hippocampus and Retrosplenial Cortex Track Homing Distance during Human Path Integration.
The Journal of neuroscience : the official journal of the Society for Neuroscience, 2015Co-Authors: Elizabeth R. Chrastil, Michael E. Hasselmo, Katherine R. Sherrill, Chantal E. SternAbstract:Path Integration, the updating of position and orientation during movement, often involves tracking a home location. Here, we examine processes that could contribute to successful location tracking in humans. In particular, we investigate a homing vector model of Path Integration, whereby a navigator continuously tracks a trajectory back to the home location. To examine this model, we developed a loop task for fMRI, in which participants viewed movement that circled back to a home location in a sparse virtual environment. In support of a homing vector system, hippocampus, retrosplenial cortex, and parahippocampal cortex were responsive to Euclidean distance from home. These results provide the first evidence of a constantly maintained homing signal in the human brain. In addition, hippocampus, retrosplenial cortex, and parahippocampal cortex, as well as medial prefrontal cortex, were recruited during successful Path Integration. These findings suggest that dynamic processes recruit hippocampus, retrosplenial cortex, and parahippocampal cortex in support of Path Integration, including a homing vector system that tracks movement relative to home. SIGNIFICANCE STATEMENT Path Integration is the continual updating of position and orientation during navigation. Animal studies have identified place cells and grid cells as important for Path Integration, but underlying models of Path Integration in humans have rarely been studied. The results of our novel loop closure task are the first to suggest that a homing vector tracks Euclidean distance from the home location, supported by the hippocampus, retrosplenial cortex, and parahippocampal cortex. These findings suggest a potential homing vector mechanism supporting Path Integration, which recruits hippocampus and retrosplenial cortex to track movement relative to home. These results provide new avenues for computational and animal models by directing attention to homing vector models of Path Integration, which differ from current movement-tracking models.
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hippocampus and retrosplenial cortex combine Path Integration signals for successful navigation
The Journal of Neuroscience, 2013Co-Authors: Katherine R. Sherrill, Michael E. Hasselmo, Chantal E. Stern, Ugur M Erdem, Robert S Ross, Thackery I BrownAbstract:The current study used fMRI in humans to examine goal-directed navigation in an open field environment. We designed a task that required participants to encode survey-level spatial information and subsequently navigate to a goal location in either first person, third person, or survey perspectives. Critically, no distinguishing landmarks or goal location markers were present in the environment, thereby requiring participants to rely on Path Integration mechanisms for successful navigation. We focused our analysis on mechanisms related to navigation and mechanisms tracking linear distance to the goal location. Successful navigation required translation of encoded survey-level map information for orientation and implementation of a planned route to the goal. Our results demonstrate that successful first and third person navigation trials recruited the anterior hippocampus more than trials when the goal location was not successfully reached. When examining only successful trials, the retrosplenial and posterior parietal cortices were recruited for goal-directed navigation in both first person and third person perspectives. Unique to first person perspective navigation, the hippocampus was recruited to Path integrate self-motion cues with location computations toward the goal location. Last, our results demonstrate that the hippocampus supports goal-directed navigation by actively tracking proximity to the goal throughout navigation. When using Path Integration mechanisms in first person and third person perspective navigation, the posterior hippocampus was more strongly recruited as participants approach the goal. These findings provide critical insight into the neural mechanisms by which we are able to use map-level representations of our environment to reach our navigational goals.
Elizabeth R. Chrastil - One of the best experts on this subject based on the ideXlab platform.
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resting state connectivity between medial temporal lobe regions and intrinsic cortical networks predicts performance in a Path Integration task
Frontiers in Human Neuroscience, 2018Co-Authors: Sarah C Izen, Chantal E. Stern, Elizabeth R. ChrastilAbstract:Humans differ in their individual navigational performance, in part because successful navigation relies on several diverse abilities. One such navigational capability is Path Integration, the updating of position and orientation during movement, typically in a sparse, landmark-free environment. This study examined the relationship between Path Integration abilities and functional connectivity to several canonical intrinsic brain networks. Intrinsic networks within the brain reflect past inputs and communication as well as structural architecture. Individual differences in intrinsic connectivity have been observed for common networks, suggesting that these networks can inform our understanding of individual spatial abilities. Here, we examined individual differences in intrinsic connectivity using resting state magnetic resonance imaging (rsMRI). We tested Path Integration ability using a loop closure task, in which participants viewed a single video of movement in a circle trajectory in a sparse environment, and then indicated whether the video ended in the same location in which it started. To examine intrinsic brain networks, participants underwent a resting state scan. We found that better performance in the loop task was associated with increased connectivity during rest between the central executive network (CEN) and posterior hippocampus, parahippocampal cortex (PHC) and entorhinal cortex. We also found that connectivity between PHC and the default mode network (DMN) during rest was associated with better loop closure performance. The results indicate that interactions between medial temporal lobe (MTL) regions and intrinsic networks that involve prefrontal cortex (PFC) are important for Path Integration and navigation.
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Rotational error in Path Integration: encoding and execution errors in angle reproduction
Experimental Brain Research, 2017Co-Authors: Elizabeth R. Chrastil, William H. WarrenAbstract:Path Integration is fundamental to human navigation. When a navigator leaves home on a complex outbound Path, they are able to keep track of their approximate position and orientation and return to their starting location on a direct homebound Path. However, there are several sources of error during Path Integration. Previous research has focused almost exclusively on encoding error —the error in registering the outbound Path in memory. Here, we also consider execution error— the error in the response, such as turning and walking a homebound trajectory. In two experiments conducted in ambulatory virtual environments, we examined the contribution of execution error to the rotational component of Path Integration using angle reproduction tasks. In the reproduction tasks, participants rotated once and then rotated again to face the original direction, either reproducing the initial turn or turning through the supplementary angle. One outstanding difficulty in disentangling encoding and execution error during a typical angle reproduction task is that as the encoding angle increases, so does the required response angle. In Experiment 1, we dissociated these two variables by asking participants to report each encoding angle using two different responses: by turning to walk on a Path parallel to the initial facing direction in the same (reproduction) or opposite (supplementary angle) direction. In Experiment 2, participants reported the encoding angle by turning both rightward and leftward onto a Path parallel to the initial facing direction, over a larger range of angles. The results suggest that execution error, not encoding error, is the predominant source of error in angular Path Integration. These findings also imply that the Path integrator uses an intrinsic (action-scaled) rather than an extrinsic (objective) metric.
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individual differences in human Path Integration abilities correlate with gray matter volume in retrosplenial cortex hippocampus and medial prefrontal cortex
eNeuro, 2017Co-Authors: Elizabeth R. Chrastil, Michael E. Hasselmo, Chantal E. Stern, Katherine R. Sherrill, Irem AselciogluAbstract:Humans differ in their individual navigational abilities. These individual differences may exist in part because successful navigation relies on several disparate abilities, which rely on different brain structures. One such navigational capability is Path Integration, the updating of position and orientation, in which navigators track distances, directions, and locations in space during movement. Although structural differences related to landmark-based navigation have been examined, gray matter volume related to Path Integration ability has not yet been tested. Here, we examined individual differences in two Path Integration paradigms: (1) a location tracking task and (2) a task tracking translational and rotational self-motion. Using voxel-based morphometry, we related differences in performance in these Path Integration tasks to variation in brain morphology in 26 healthy young adults. Performance in the location tracking task positively correlated with individual differences in gray matter volume in three areas critical for Path Integration: the hippocampus, the retrosplenial cortex, and the medial prefrontal cortex. These regions are consistent with the Path Integration system known from computational and animal models and provide novel evidence that morphological variability in retrosplenial and medial prefrontal cortices underlies individual differences in human Path Integration ability. The results for tracking rotational self-motion-but not translation or location-demonstrated that cerebellum gray matter volume correlated with individual performance. Our findings also suggest that these three aspects of Path Integration are largely independent. Together, the results of this study provide a link between individual abilities and the functional correlates, computational models, and animal models of Path Integration.
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which way and how far tracking of translation and rotation information for human Path Integration
Human Brain Mapping, 2016Co-Authors: Michael E. Hasselmo, Chantal E. Stern, Elizabeth R. Chrastil, Katherine R. SherrillAbstract:Path Integration, the constant updating of the navigator's knowledge of position and orientation during movement, requires both visuospatial knowledge and memory. This study aimed to develop a systems-level understanding of human Path Integration by examining the basic building blocks of Path Integration in humans. To achieve this goal, we used functional imaging to examine the neural mechanisms that support the tracking and memory of translational and rotational components of human Path Integration. Critically, and in contrast to previous studies, we examined movement in translation and rotation tasks with no defined end-point or goal. Navigators accumulated translational and rotational information during virtual self-motion. Activity in hippocampus, retrosplenial cortex (RSC), and parahippocampal cortex (PHC) increased during both translation and rotation encoding, suggesting that these regions track self-motion information during Path Integration. These results address current questions regarding distance coding in the human brain. By implementing a modified delayed match to sample paradigm, we also examined the encoding and maintenance of Path Integration signals in working memory. Hippocampus, PHC, and RSC were recruited during successful encoding and maintenance of Path Integration information, with RSC selective for tasks that required processing heading rotation changes. These data indicate distinct working memory mechanisms for translation and rotation, which are essential for updating neural representations of current location. The results provide evidence that hippocampus, PHC, and RSC flexibly track task-relevant translation and rotation signals for Path Integration and could form the hub of a more distributed network supporting spatial navigation. Hum Brain Mapp 37:3636-3655, 2016. © 2016 Wiley Periodicals, Inc.
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There and Back Again: Hippocampus and Retrosplenial Cortex Track Homing Distance during Human Path Integration.
The Journal of neuroscience : the official journal of the Society for Neuroscience, 2015Co-Authors: Elizabeth R. Chrastil, Michael E. Hasselmo, Katherine R. Sherrill, Chantal E. SternAbstract:Path Integration, the updating of position and orientation during movement, often involves tracking a home location. Here, we examine processes that could contribute to successful location tracking in humans. In particular, we investigate a homing vector model of Path Integration, whereby a navigator continuously tracks a trajectory back to the home location. To examine this model, we developed a loop task for fMRI, in which participants viewed movement that circled back to a home location in a sparse virtual environment. In support of a homing vector system, hippocampus, retrosplenial cortex, and parahippocampal cortex were responsive to Euclidean distance from home. These results provide the first evidence of a constantly maintained homing signal in the human brain. In addition, hippocampus, retrosplenial cortex, and parahippocampal cortex, as well as medial prefrontal cortex, were recruited during successful Path Integration. These findings suggest that dynamic processes recruit hippocampus, retrosplenial cortex, and parahippocampal cortex in support of Path Integration, including a homing vector system that tracks movement relative to home. SIGNIFICANCE STATEMENT Path Integration is the continual updating of position and orientation during navigation. Animal studies have identified place cells and grid cells as important for Path Integration, but underlying models of Path Integration in humans have rarely been studied. The results of our novel loop closure task are the first to suggest that a homing vector tracks Euclidean distance from the home location, supported by the hippocampus, retrosplenial cortex, and parahippocampal cortex. These findings suggest a potential homing vector mechanism supporting Path Integration, which recruits hippocampus and retrosplenial cortex to track movement relative to home. These results provide new avenues for computational and animal models by directing attention to homing vector models of Path Integration, which differ from current movement-tracking models.
Rüdiger Wehner - One of the best experts on this subject based on the ideXlab platform.
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Path Integration provides a scaffold for landmark learning in desert ants
Current Biology, 2010Co-Authors: M. Müller, Rüdiger WehnerAbstract:Summary On leaving the nest [1–9] or a newly discovered food site [10–12] for the first time, bees and wasps perform elaborate flight maneuvers to learn the location of their goal and the lay of the land surrounding it. In all these orientation flights the insects turn back and look [13] at the goal, which they can visually locate by landmark cues directly defining the goal. Here we show that Namibian desert ants, Ocymyrmex , when learning new landmarks in the neighborhood of the goal, acquire this landmark information when they cannot see the goal. They do so by performing well-choreographed rotation movements integrated in spiral-like "learning walks." Within these rotations, short (about 150 ms) stopping phases occur, during which the ants orient themselves in the direction of the nest entrance. On the barren sand surface the nest entrance is invisible, so the ants can aim at it only by reading out the current state of their Path integrator [14–17]. Hence, they could associate "snapshot" views [18–20] taken of the nest surroundings during the stopping phases with Path Integration coordinates. In bees and ants such associations have often been discussed, but evidence has not been obtained yet [15, 20–22].
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Path Integration in a three dimensional maze ground distance estimation keeps desert ants cataglyphis fortis on course
The Journal of Experimental Biology, 2005Co-Authors: Gunnar Grah, Rüdiger Wehner, Bernhard RonacherAbstract:In this study, we investigate the ability of desert ants to gauge the ground distances of sloped sections in a three-dimensional (3D) outbound Path. Ground distance estimation, as opposed to a simple measurement of walking distances, is a necessary prerequisite for precise Path Integration in undulating terrain. We trained ants to visit a feeder along a Path that included an angular turn as well as a 'hill', resulting in an outbound Path with a distinct 3D structure. We then observed the ants' return Path in a test field on level ground. From the angles of the ants' return Path on the test field one can infer which property of the hill segment was fed into the ants' Path Integration module, the actual walking distance or the ground distance. The results show clearly that it is the ground distance that Cataglyphis fortis feeds into its Path integrator, and suggest that the ants are able to keep an accurate home vector also in hilly terrain.
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idiosyncratic route based memories in desert ants melophorus bagoti how do they interact with Path Integration vectors
Neurobiology of Learning and Memory, 2005Co-Authors: Martin Kohler, Rüdiger WehnerAbstract:Individually foraging desert ants of central Australia, Melophorus bagoti, exhibit amazingly precise mechanisms of visual landmark guidance when navigating through cluttered environments. If trained to shuttle back and forth between the nest and a feeder, they establish habitual outbound and inbound routes, which guide them idiosyncratically across the natural maze of extended arrays of grass tussocks covering their foraging areas. The route-based memories that usually differ between outbound and inbound runs are acquired already during the first runs to the nest and feeder. If the ants are displaced sideways of their habitual routes, they can enter their stereotyped routes at any place and then follow these routes with the same accuracy as if they had started at the usual point of departure. Furthermore, the accuracy of maintaining a route does not depend on whether homebound ants have been captured at the feeder shortly before starting their home run and, hence, with their home vector still fully available (full-vector ants), or whether they have been captured at the nest after they had already completed their home run (zero-vector ants). Hence, individual landmark memories can be retrieved independently of the state of the Path-Integration vector with which they have been associated during the acquisition phase of learning. However, the ants display their Path-Integration vector when displaced from the feeder to unfamiliar territory.
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Path Integration in desert ants cataglyphis how to make a homing ant run away from home
Proceedings of The Royal Society B: Biological Sciences, 2004Co-Authors: David Andel, Rüdiger WehnerAbstract:Path Integration is an ant's lifeline on any of its foraging journeys. It results in a homebound global vector that continually informs the animal about its position relative to its starting point. Here, we use a particular (repeated training and displacement) paradigm, in which homebound ants are made to follow a familiar landmark route repeatedly from the feeder to the nest, even after they have arrived at the nest. The results show that during the repeated landmark-guided home runs the ant's Path integrator runs continually, so that the current state of the homebound vector increasingly exceeds the reference state. The dramatic result is that the homing ants run away from home. This finding implies that the ants do not rely on cartographic information about the locations of nest and feeder (e.g. that the nest is always south of the feeder), but just behave according to what the state of their egocentric Path integrator tells them.
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do familiar landmarks reset the global Path Integration system of desert ants
The Journal of Experimental Biology, 2003Co-Authors: Matthew Collett, Thomas S Collett, S Chameron, Rüdiger WehnerAbstract:It is often suggested that animals may link landmark memories to a global coordinate system provided by Path Integration, thereby obtaining a map-like representation of familiar terrain. In an attempt to discover if desert ants form such associations we have performed experiments that test whether desert ants recall a long-term memory of a global Path Integration vector on arriving at a familiar food site. Ants from three nests were trained along L-shaped routes to a feeder. Each route was entirely within open-topped channels that obscured all natural landmarks. Conspicuous artificial landmarks were attached to the channelling that formed the latter part of the route. The homeward vectors of ants accustomed to the route were tested with the foodward route, either as in training, or with the first leg of the L shortened or extended. These ants were taken from the feeder to a test area and released, whereupon they performed a home vector. If travelling the latter part of a familiar route and arriving at a familiar food site triggers the recall of an accustomed home vector, then the home vector should be the same under both test conditions. We find instead that the home vector tended to reflect the immediately preceding outward journey. In conjunction with earlier work, these experiments led us to conclude in the case of desert ants that landmark memories do not prime the recall of long-term global Path Integration memories. On the other hand, landmark memories are known to be linked to local Path Integration vectors that guide ants along a segment of a route. Landmarks thus seem to provide procedural information telling ants what action to perform next but not the positional information that gives an ant its location relative to its nest.
Thomas W Cronin - One of the best experts on this subject based on the ideXlab platform.
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mantis shrimp navigate home using celestial and idiothetic Path Integration
Current Biology, 2020Co-Authors: Rickesh N Patel, Thomas W CroninAbstract:Path Integration is a robust mechanism that many animals employ to return to specific locations, typically their homes, during navigation. This efficient navigational strategy has never been demonstrated in a fully aquatic animal, where sensory cues used for orientation may differ dramatically from those available above the water's surface. Here, we report that the mantis shrimp, Neogonodactylus oerstedii, uses Path Integration informed by a hierarchical reliance on the sun, overhead polarization patterns, and idiothetic (internal) orientation cues to return home when foraging, making them the first fully aquatic Path-integrating animals yet discovered. We show that mantis shrimp rely on navigational strategies closely resembling those used by insect navigators, opening a new avenue for the investigation of the neural basis of navigation behaviors and the evolution of these strategies in arthropods and potentially other animals as well. VIDEO ABSTRACT.
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mantis shrimp navigate home using celestial and idiothetic Path Integration
Social Science Research Network, 2020Co-Authors: Rickesh N Patel, Thomas W CroninAbstract:Path Integration is a robust mechanism that many animals employ to return to specific locations, typically their homes, during navigation. This efficient navigational strategy has never been demonstrated in a fully aquatic animal, where sensory cues used for orientation may differ dramatically from those available above the water’s surface. Here we report that the mantis shrimp, Neogonodactylus oerstedii, uses Path Integration informed by a hierarchical reliance on the sun, overhead polarization patterns, and idiothetic (internal) orientation cues to return home when foraging, making them the first fully aquatic Path-integrating animals yet discovered. We show that mantis shrimp rely on navigational strategies closely resembling those used by insect navigators, opening a new avenue for the investigation of the neural basis of navigation behaviors and the evolution of these strategies in arthropods and potentially other animals as well.
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Path Integration error and adaptable search behaviors in a mantis shrimp
bioRxiv, 2020Co-Authors: Rickesh N Patel, Thomas W CroninAbstract:Abstract Mantis shrimp of the species Neogonodactylus oerstedii occupy small burrows in shallow waters throughout the Caribbean. These animals use Path Integration, a vector-based navigation strategy, to return to their homes while foraging. Here we report that Path Integration in N. oerstedii is prone to error accumulated during outward foraging Paths and we describe the search behavior that N. oerstedii employs after it fails to locate its home following the route provided by its Path integrator. This search behavior forms continuously expanding, non-oriented loops that are centered near the point of search initiation. The radius of this search is apparently scaled to the animal’s accumulated error during Path Integration, improving the effectiveness of the search. The search behaviors exhibited by N. oerstedii bear a striking resemblance to search behaviors in other animals, offering potential avenues for the comparative examination of search behaviors and how they are optimized in disparate taxa. Summary Statement Mantis shrimp use Path Integration, an error-prone navigational strategy, when travelling home. When Path Integration fails, mantis shrimp employ a stereotyped yet flexible search pattern to locate their homes.
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Path Integration error and adaptable search behaviors in a mantis shrimp
The Journal of Experimental Biology, 2020Co-Authors: Rickesh N Patel, Thomas W CroninAbstract:Mantis shrimp of the species Neogonodactylus oerstedii occupy small burrows in shallow waters throughout the Caribbean. These animals use Path Integration, a vector-based navigation strategy, to return to their homes while foraging. Here we report that Path Integration in N. oerstedii is prone to error accumulated during outward foraging Paths and we describe the search behavior that N. oerstedii employs after it fails to locate its home following the route provided by its Path integrator. This search behavior forms continuously expanding, non-oriented loops that are centered near the point of search initiation. The radius of this search is scaled to the animal9s positional uncertainty during Path Integration, improving the effectiveness of the search. The search behaviors exhibited by N. oerstedii bear a striking resemblance to search behaviors in other animals, offering potential avenues for the comparative examination of search behaviors and how they are optimized in disparate taxa.
Bruce L Mcnaughton - One of the best experts on this subject based on the ideXlab platform.
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vision and locomotion combine to drive Path Integration sequences in mouse retrosplenial cortex
Current Biology, 2020Co-Authors: Bruce L Mcnaughton, Dun Mao, Leonardo A Molina, Vincent BoninAbstract:Summary The retrosplenial cortex (RSC) is involved in a broad range of cognitive functions, integrating rich sensory, motor, and spatial signals from multiple brain areas, including the hippocampal system. RSC neurons show hippocampus-dependent activity reminiscent of place cell sequences. Using cellular calcium imaging in a virtual reality (VR)-based locomotion task, we investigate how the Integration of visual and locomotor inputs may give rise to such activity in RSC. A substantial population shows neural sequences that track position in the VR environment. This activity is driven by the conjunction of visual stimuli sequences and active movement, which is suggestive of Path Integration. The activity is anchored to a reference point and predominantly follows the VR upon manipulations of optic flow against locomotion. Thus, locomotion-gated optic flow, combined with the presence of contextual cues at the start of each trial, is sufficient to drive the sequential activity. A subpopulation shows landmark-related visual responses that are modulated by animal’s position in the VR. Thus, rather than fragmenting the spatial representation into equivalent locomotion-based ensemble versus optic-flow-based ensemble, in RSC, optic flow appears to override locomotion signals coherently in the population, when the gain between the two signals is altered.
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Path Integration and the neural basis of the 'cognitive map'
Nat Rev Neurosci, 2006Co-Authors: Bruce L Mcnaughton, F. P. Battaglia, Edvard I. Moser, O Jensen, M. B. MoserAbstract:The hippocampal formation can encode relative spatial location, without reference to external cues, by the Integration of linear and angular self-motion (Path Integration). Theoretical studies, in conjunction with recent empirical discoveries, suggest that the medial entorhinal cortex (MEC) might perform some of the essential underlying computations by means of a unique, periodic synaptic matrix that could be self-organized in early development through a simple, symmetry-breaking operation. The scale at which space is represented increases systematically along the dorsoventral axis in both the hippocampus and the MEC, apparently because of systematic variation in the gain of a movement-speed signal. Convergence of spatially periodic input at multiple scales, from so-called grid cells in the entorhinal cortex, might result in non-periodic spatial firing patterns (place fields) in the hippocampus.
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influence of Path Integration versus environmental orientation on place cell remapping between visually identical environments
Journal of Neurophysiology, 2005Co-Authors: Mark C. Fuhs, Bruce L Mcnaughton, Shea R Vanrhoads, Amanda E Casale, David S. TouretzkyAbstract:To assess the effects of interactions between angular Path Integration and visual landmarks on the firing of hippocampal neurons, we recorded from CA1 pyramidal cells as rats foraged in two identic...
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Dynamics of Mismatch Correction in the Hippocampal Ensemble Code for Space: Interaction between Path Integration and Environmental Cues
The Journal of neuroscience, 1996Co-Authors: Katalin M Gothard, William E Skaggs, Bruce L McnaughtonAbstract:Populations of hippocampal neurons were recorded simulta-neously in rats shuttling on a track between a fixed reward site at one end and a movable reward site, mounted in a sliding box, at the opposite end. While the rat ran toward the fixed site, the box was moved. The rat returned to the box in its new position. On the initial part of all journeys, cells fired at fixed distances from the origin, whereas on the final part, cells fired at fixed distances from the destination. Thus, on outward journeys from the box, with the box behind the rat, the position representation must have been updated by Path Integration. Farther along the journey, the place field map became aligned on the basis of external stimuli. The spatial representation was quantified in terms of population vectors. During shortened journeys, the vector shifted from an alignment with the origin to an alignment with the destination. The dynamics depended on the degree of mismatch with respect to the full-length journey. For small mismatches, the vector moved smoothly through intervening coordinates until the mismatch was corrected. For large mis-matches, it jumped abruptly to the new coordinate. Thus, when mismatches occur, Path Integration and external cues interact competitively to control place-cell firing. When the same box was used in a different environment, it controlled the alignment of a different set of place cells. These data suggest that although map alignment can be controlled by landmarks, hippocampal neurons do not explicitly represent objects or events.
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deciphering the hippocampal polyglot the hippocampus as a Path Integration system
The Journal of Experimental Biology, 1996Co-Authors: Bruce L Mcnaughton, Katalin M Gothard, William E Skaggs, James J. Knierim, Carol A Barnes, Jason L Gerrard, M W Jung, Hemant S Kudrimoti, Yulin Qin, M SusterAbstract:Hippocampal 'place' cells and the head-direction cells of the dorsal presubiculum and related neocortical and thalamic areas appear to be part of a preconfigured network that generates an abstract internal representation of two-dimensional space whose metric is self-motion. It appears that viewpoint-specific visual information (e.g. landmarks) becomes secondarily bound to this structure by associative learning. These associations between landmarks and the preconfigured Path integrator serve to set the origin for Path Integration and to correct for cumulative error. In the absence of familiar landmarks, or in darkness without a prior spatial reference, the system appears to adopt an initial reference for Path Integration independently of external cues. A hypothesis of how the Path Integration system may operate at the neuronal level is proposed.
