The Experts below are selected from a list of 207 Experts worldwide ranked by ideXlab platform
Robert E Clark - One of the best experts on this subject based on the ideXlab platform.
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recent and remote retrograde Memory deficit in rats with medial entorhinal cortex lesions
Neurobiology of Learning and Memory, 2018Co-Authors: Jena B. Hales, Stefan Leutgeb, Jonathan L Vincze, Nicole T Reitz, Amber C Ocampo, Robert E ClarkAbstract:The hippocampus is critically involved in the acquisition and retrieval of spatial memories. Even though some memories become independent of the hippocampus over time, expression of spatial memories have consistently been found to permanently depend on the hippocampus. Recent studies have focused on the adjacent medial entorhinal cortex (MEC), as it provides major projections to the hippocampus. These studies have shown that lesions of the MEC disrupt spatial processing in the hippocampus and impair spatial Memory acquisition on the watermaze task. MEC lesions acquired after learning the watermaze task also disrupt recently acquired spatial memories. However, the effect of MEC lesions on remotely acquired memories is unknown. The current study examined the effect of MEC lesions on recent and remote Memory retrieval using three hippocampus-dependent tasks: the watermaze, trace fear conditioning, and novel object recognition. MEC lesions caused impaired retrieval of recently and remotely acquired Memory for the watermaze. Rats with MEC lesions also showed impaired fear Memory when exposed to the previously conditioned context or the associated tone, and this reduction was seen both when the lesion occurred soon after trace fear condition and when it occurred a month after conditioning. In contrast, MEC lesions did not disrupt novel object recognition. These findings indicate that even with an intact hippocampus, rats with MEC lesions cannot retrieve recent or remote spatial memories. In addition, the involvement of the MEC in Memory extends beyond is role in navigation and Place Memory.
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medial entorhinal cortex lesions only partially disrupt hippocampal Place cells and hippocampus dependent Place Memory
Cell Reports, 2014Co-Authors: Jena B. Hales, Stefan Leutgeb, Jill K. Leutgeb, Magdalene I. Schlesiger, Larry R Squire, Robert E ClarkAbstract:The entorhinal cortex provides the primary cortical projections to the hippocampus, a brain structure critical for Memory. However, it remains unclear how the precise firing patterns of medial entorhinal cortex (MEC) cells influence hippocampal physiology and hippocampus-dependent behavior. We found that complete bilateral lesions of the MEC resulted in a lower proportion of active hippocampal cells. The remaining active cells had Place fields, but with decreased spatial precision and decreased long-term spatial stability. In addition, MEC rats were as impaired in the water maze as hippocampus rats, while rats with combined MEC and hippocampal lesions had an even greater deficit. However, MEC rats were not impaired on other hippocampus-dependent tasks, including those in which an object location or context was remembered. Thus, the MEC is not necessary for all types of spatial coding or for all types of hippocampus-dependent Memory, but it is necessary for the normal acquisition of Place Memory.
Morgan D Barense - One of the best experts on this subject based on the ideXlab platform.
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object in Place Memory predicted by anterolateral entorhinal cortex and parahippocampal cortex volume in older adults
Journal of Cognitive Neuroscience, 2019Co-Authors: Lokkin Yeung, Rosanna K Olsen, Bryan Hong, Valentina Mihajlovic, Maria C Dangelo, Arber Kacollja, Jennifer D Ryan, Morgan D BarenseAbstract:The lateral portion of the entorhinal cortex is one of the first brain regions affected by tau pathology, an important biomarker for Alzheimer disease. Improving our understanding of this region's ...
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object in Place Memory predicted by anterolateral entorhinal cortex and parahippocampal cortex volume in older adults
Journal of Cognitive Neuroscience, 2019Co-Authors: Lokkin Yeung, Rosanna K Olsen, Bryan Hong, Valentina Mihajlovic, Maria C Dangelo, Arber Kacollja, Jennifer D Ryan, Morgan D BarenseAbstract:The lateral portion of the entorhinal cortex is one of the first brain regions affected by tau pathology, an important biomarker for Alzheimer disease. Improving our understanding of this region's cognitive role may help identify better cognitive tests for early detection of Alzheimer disease. Based on its functional connections, we tested the idea that the human anterolateral entorhinal cortex (alERC) may play a role in integrating spatial information into object representations. We recently demonstrated that the volume of the alERC was related to processing the spatial relationships of the features within an object [Yeung, L. K., Olsen, R. K., Bild-Enkin, H. E. P., D'Angelo, M. C., Kacollja, A., McQuiggan, D. A., et al. Anterolateral entorhinal cortex volume predicted by altered intra-item configural processing. Journal of Neuroscience, 37, 5527-5538, 2017]. In this study, we investigated whether the human alERC might also play a role in processing the spatial relationships between an object and its environment using an eye-tracking task that assessed visual fixations to a critical object within a scene. Guided by rodent work, we measured both object-in-Place Memory, the association of an object with a given context [Wilson, D. I., Langston, R. F., Schlesiger, M. I., Wagner, M., Watanabe, S., & Ainge, J. A. Lateral entorhinal cortex is critical for novel object-context recognition. Hippocampus, 23, 352-366, 2013], and object-trace Memory, the Memory for the former location of objects [Tsao, A., Moser, M. B., & Moser, E. I. Traces of experience in the lateral entorhinal cortex. Current Biology, 23, 399-405, 2013]. In a group of older adults with varying stages of brain atrophy and cognitive decline, we found that the volume of the alERC and the volume of the parahippocampal cortex selectively predicted object-in-Place Memory, but not object-trace Memory. These results provide support for the notion that the alERC may integrate spatial information into object representations.
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object in Place Memory predicted by anterolateral entorhinal cortex and parahippocampal cortex volume in older adults
bioRxiv, 2018Co-Authors: Lokkin Yeung, Rosanna K Olsen, Bryan Hong, Valentina Mihajlovic, Maria C Dangelo, Arber Kacollja, Jennifer D Ryan, Morgan D BarenseAbstract:The lateral portion of the entorhinal cortex is one of the first brain regions affected by tau pathology, an important biomarker for Alzheimer's disease (AD). Improving our understanding of this region's cognitive role may help identify better cognitive tests for early detection of AD. Based on its functional connections, we tested the idea that the human anterolateral entorhinal cortex (alERC) may play a role in integrating spatial information into object representations. We recently demonstrated that the volume of the alERC was related to processing the spatial relationships of the features within an object (Yeung et al., 2017). In the present study, we investigated whether the human alERC might also play a role in processing the spatial relationships between an object and its environment using an eyetracking task that assessed visual fixations to a critical object within a scene. Guided by rodent work, we measured both object-in-Place Memory, the association of an object with a given context (Wilson et al., 2013), and object-trace Memory, the Memory for the former location of objects (Tsao, Moser, & Moser, 2013). In a group of older adults with varying stages of brain atrophy and cognitive decline, we found that the volume of the alERC and the volume of the parahippocampal cortex (PHC) selectively predicted object-in-Place Memory, but not object-trace Memory. These results provide support for the notion that the alERC may integrate spatial information into object representations.
Emma R Wood - One of the best experts on this subject based on the ideXlab platform.
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associative recognition and the hippocampus differential effects of hippocampal lesions on object Place object context and object Place context Memory
Hippocampus, 2009Co-Authors: Rosamund F Langston, Emma R WoodAbstract:The hippocampus is thought to be required for the associative recognition of objects together with the spatial or temporal contexts in which they occur. However, recent data showing that rats with fornix lesions perform as well as controls in an object-Place task, while being impaired on an object-Place-context task (Eacott and Norman (2004) J Neurosci 24:1948–1953), suggest that not all forms of context-dependent associative recognition depend on the integrity of the hippocampus. To examine the role of the hippocampus in context-dependent recognition directly, the present study tested the effects of large, selective, bilateral hippocampus lesions in rats on performance of a series of spontaneous recognition Memory tasks: object recognition, object-Place recognition, object-context recognition and object-Place-context recognition. Consistent with the effects of fornix lesions, animals with hippocampus lesions were impaired only on the object-Place-context task. These data confirm that not all forms of context-dependent associative recognition are mediated by the hippocampus. Subsequent experiments suggested that the object-Place task does not require an allocentric representation of space, which could account for the lack of impairment following hippocampus lesions. Importantly, as the object-Place-context task has similar spatial requirements, the selective deficit in object-Place-context recognition suggests that this task requires hippocampus-dependent neural processes distinct from those required for allocentric spatial Memory, or for object Memory, object-Place Memory or object-context Memory. Two possibilities are that object, Place, and context information converge only in the hippocampus, or that recognition of integrated object-Place-context information requires a hippocampus-dependent mode of retrieval, such as recollection. © 2009 Wiley-Liss, Inc.
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associative recognition and the hippocampus differential effects of hippocampal lesions on object Place object context and object Place context Memory
Hippocampus, 2009Co-Authors: Rosamund F Langston, Emma R WoodAbstract:The hippocampus is thought to be required for the associative recognition of objects together with the spatial or temporal contexts in which they occur. However, recent data showing that rats with fornix lesions perform as well as controls in an object-Place task, while being impaired on an object-Place-context task (Eacott and Norman (2004) J Neurosci 24:1948-1953), suggest that not all forms of context-dependent associative recognition depend on the integrity of the hippocampus. To examine the role of the hippocampus in context-dependent recognition directly, the present study tested the effects of large, selective, bilateral hippocampus lesions in rats on performance of a series of spontaneous recognition Memory tasks: object recognition, object-Place recognition, object-context recognition and object-Place-context recognition. Consistent with the effects of fornix lesions, animals with hippocampus lesions were impaired only on the object-Place-context task. These data confirm that not all forms of context-dependent associative recognition are mediated by the hippocampus. Subsequent experiments suggested that the object-Place task does not require an allocentric representation of space, which could account for the lack of impairment following hippocampus lesions. Importantly, as the object-Place-context task has similar spatial requirements, the selective deficit in object-Place-context recognition suggests that this task requires hippocampus-dependent neural processes distinct from those required for allocentric spatial Memory, or for object Memory, object-Place Memory or object-context Memory. Two possibilities are that object, Place, and context information converge only in the hippocampus, or that recognition of integrated object-Place-context information requires a hippocampus-dependent mode of retrieval, such as recollection.
Jena B. Hales - One of the best experts on this subject based on the ideXlab platform.
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recent and remote retrograde Memory deficit in rats with medial entorhinal cortex lesions
Neurobiology of Learning and Memory, 2018Co-Authors: Jena B. Hales, Stefan Leutgeb, Jonathan L Vincze, Nicole T Reitz, Amber C Ocampo, Robert E ClarkAbstract:The hippocampus is critically involved in the acquisition and retrieval of spatial memories. Even though some memories become independent of the hippocampus over time, expression of spatial memories have consistently been found to permanently depend on the hippocampus. Recent studies have focused on the adjacent medial entorhinal cortex (MEC), as it provides major projections to the hippocampus. These studies have shown that lesions of the MEC disrupt spatial processing in the hippocampus and impair spatial Memory acquisition on the watermaze task. MEC lesions acquired after learning the watermaze task also disrupt recently acquired spatial memories. However, the effect of MEC lesions on remotely acquired memories is unknown. The current study examined the effect of MEC lesions on recent and remote Memory retrieval using three hippocampus-dependent tasks: the watermaze, trace fear conditioning, and novel object recognition. MEC lesions caused impaired retrieval of recently and remotely acquired Memory for the watermaze. Rats with MEC lesions also showed impaired fear Memory when exposed to the previously conditioned context or the associated tone, and this reduction was seen both when the lesion occurred soon after trace fear condition and when it occurred a month after conditioning. In contrast, MEC lesions did not disrupt novel object recognition. These findings indicate that even with an intact hippocampus, rats with MEC lesions cannot retrieve recent or remote spatial memories. In addition, the involvement of the MEC in Memory extends beyond is role in navigation and Place Memory.
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medial entorhinal cortex lesions only partially disrupt hippocampal Place cells and hippocampus dependent Place Memory
Cell Reports, 2014Co-Authors: Jena B. Hales, Stefan Leutgeb, Jill K. Leutgeb, Magdalene I. Schlesiger, Larry R Squire, Robert E ClarkAbstract:The entorhinal cortex provides the primary cortical projections to the hippocampus, a brain structure critical for Memory. However, it remains unclear how the precise firing patterns of medial entorhinal cortex (MEC) cells influence hippocampal physiology and hippocampus-dependent behavior. We found that complete bilateral lesions of the MEC resulted in a lower proportion of active hippocampal cells. The remaining active cells had Place fields, but with decreased spatial precision and decreased long-term spatial stability. In addition, MEC rats were as impaired in the water maze as hippocampus rats, while rats with combined MEC and hippocampal lesions had an even greater deficit. However, MEC rats were not impaired on other hippocampus-dependent tasks, including those in which an object location or context was remembered. Thus, the MEC is not necessary for all types of spatial coding or for all types of hippocampus-dependent Memory, but it is necessary for the normal acquisition of Place Memory.
Lokkin Yeung - One of the best experts on this subject based on the ideXlab platform.
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object in Place Memory predicted by anterolateral entorhinal cortex and parahippocampal cortex volume in older adults
Journal of Cognitive Neuroscience, 2019Co-Authors: Lokkin Yeung, Rosanna K Olsen, Bryan Hong, Valentina Mihajlovic, Maria C Dangelo, Arber Kacollja, Jennifer D Ryan, Morgan D BarenseAbstract:The lateral portion of the entorhinal cortex is one of the first brain regions affected by tau pathology, an important biomarker for Alzheimer disease. Improving our understanding of this region's ...
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object in Place Memory predicted by anterolateral entorhinal cortex and parahippocampal cortex volume in older adults
Journal of Cognitive Neuroscience, 2019Co-Authors: Lokkin Yeung, Rosanna K Olsen, Bryan Hong, Valentina Mihajlovic, Maria C Dangelo, Arber Kacollja, Jennifer D Ryan, Morgan D BarenseAbstract:The lateral portion of the entorhinal cortex is one of the first brain regions affected by tau pathology, an important biomarker for Alzheimer disease. Improving our understanding of this region's cognitive role may help identify better cognitive tests for early detection of Alzheimer disease. Based on its functional connections, we tested the idea that the human anterolateral entorhinal cortex (alERC) may play a role in integrating spatial information into object representations. We recently demonstrated that the volume of the alERC was related to processing the spatial relationships of the features within an object [Yeung, L. K., Olsen, R. K., Bild-Enkin, H. E. P., D'Angelo, M. C., Kacollja, A., McQuiggan, D. A., et al. Anterolateral entorhinal cortex volume predicted by altered intra-item configural processing. Journal of Neuroscience, 37, 5527-5538, 2017]. In this study, we investigated whether the human alERC might also play a role in processing the spatial relationships between an object and its environment using an eye-tracking task that assessed visual fixations to a critical object within a scene. Guided by rodent work, we measured both object-in-Place Memory, the association of an object with a given context [Wilson, D. I., Langston, R. F., Schlesiger, M. I., Wagner, M., Watanabe, S., & Ainge, J. A. Lateral entorhinal cortex is critical for novel object-context recognition. Hippocampus, 23, 352-366, 2013], and object-trace Memory, the Memory for the former location of objects [Tsao, A., Moser, M. B., & Moser, E. I. Traces of experience in the lateral entorhinal cortex. Current Biology, 23, 399-405, 2013]. In a group of older adults with varying stages of brain atrophy and cognitive decline, we found that the volume of the alERC and the volume of the parahippocampal cortex selectively predicted object-in-Place Memory, but not object-trace Memory. These results provide support for the notion that the alERC may integrate spatial information into object representations.
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object in Place Memory predicted by anterolateral entorhinal cortex and parahippocampal cortex volume in older adults
bioRxiv, 2018Co-Authors: Lokkin Yeung, Rosanna K Olsen, Bryan Hong, Valentina Mihajlovic, Maria C Dangelo, Arber Kacollja, Jennifer D Ryan, Morgan D BarenseAbstract:The lateral portion of the entorhinal cortex is one of the first brain regions affected by tau pathology, an important biomarker for Alzheimer's disease (AD). Improving our understanding of this region's cognitive role may help identify better cognitive tests for early detection of AD. Based on its functional connections, we tested the idea that the human anterolateral entorhinal cortex (alERC) may play a role in integrating spatial information into object representations. We recently demonstrated that the volume of the alERC was related to processing the spatial relationships of the features within an object (Yeung et al., 2017). In the present study, we investigated whether the human alERC might also play a role in processing the spatial relationships between an object and its environment using an eyetracking task that assessed visual fixations to a critical object within a scene. Guided by rodent work, we measured both object-in-Place Memory, the association of an object with a given context (Wilson et al., 2013), and object-trace Memory, the Memory for the former location of objects (Tsao, Moser, & Moser, 2013). In a group of older adults with varying stages of brain atrophy and cognitive decline, we found that the volume of the alERC and the volume of the parahippocampal cortex (PHC) selectively predicted object-in-Place Memory, but not object-trace Memory. These results provide support for the notion that the alERC may integrate spatial information into object representations.