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  1. Article ; Online: Predictive learning by a burst-dependent learning rule.

    Chapman, G William / Hasselmo, Michael E

    Neurobiology of learning and memory

    2023  Volume 205, Page(s) 107826

    Abstract: Humans and other animals are able to quickly generalize latent dynamics of spatiotemporal sequences, often from a minimal number of previous experiences. Additionally, internal representations of external stimuli must remain stable, even in the presence ... ...

    Abstract Humans and other animals are able to quickly generalize latent dynamics of spatiotemporal sequences, often from a minimal number of previous experiences. Additionally, internal representations of external stimuli must remain stable, even in the presence of sensory noise, in order to be useful for informing behavior. In contrast, typical machine learning approaches require many thousands of samples, and generalize poorly to unexperienced examples, or fail completely to predict at long timescales. Here, we propose a novel neural network module which incorporates hierarchy and recurrent feedback terms, constituting a simplified model of neocortical microcircuits. This microcircuit predicts spatiotemporal trajectories at the input layer using a temporal error minimization algorithm. We show that this module is able to predict with higher accuracy into the future compared to traditional models. Investigating this model we find that successive predictive models learn representations which are increasingly removed from the raw sensory space, namely as successive temporal derivatives of the positional information. Next, we introduce a spiking neural network model which implements the rate-model through the use of a recently proposed biological learning rule utilizing dual-compartment neurons. We show that this network performs well on the same tasks as the mean-field models, by developing intrinsic dynamics that follow the dynamics of the external stimulus, while coordinating transmission of higher-order dynamics. Taken as a whole, these findings suggest that hierarchical temporal abstraction of sequences, rather than feed-forward reconstruction, may be responsible for the ability of neural systems to quickly adapt to novel situations.
    MeSH term(s) Animals ; Humans ; Neural Networks, Computer ; Neurons/physiology ; Models, Neurological
    Language English
    Publishing date 2023-09-09
    Publishing country United States
    Document type Journal Article
    ZDB-ID 1223366-3
    ISSN 1095-9564 ; 1074-7427
    ISSN (online) 1095-9564
    ISSN 1074-7427
    DOI 10.1016/j.nlm.2023.107826
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Article ; Online: Introduction to part two of the special issue on computational models of hippocampus and related structures.

    Hasselmo, Michael E

    Hippocampus

    2020  Volume 30, Issue 12, Page(s) 1328–1331

    Abstract: Extensive computational modeling has focused on the hippocampal formation and related cortical structures. This introduction describes the topics addressed by individual articles in part two of this special issue of the journal Hippocampus on the topic ... ...

    Abstract Extensive computational modeling has focused on the hippocampal formation and related cortical structures. This introduction describes the topics addressed by individual articles in part two of this special issue of the journal Hippocampus on the topic of computational models of the hippocampus and related structures.
    MeSH term(s) Animals ; Entorhinal Cortex/physiology ; Hippocampus/physiology ; Humans ; Models, Neurological ; Neural Networks, Computer ; Neurons/physiology ; Spatial Behavior/physiology ; Spatial Navigation/physiology
    Language English
    Publishing date 2020-11-13
    Publishing country United States
    Document type Introductory Journal Article ; Research Support, N.I.H., Extramural ; Research Support, U.S. Gov't, Non-P.H.S.
    ZDB-ID 1074352-2
    ISSN 1098-1063 ; 1050-9631
    ISSN (online) 1098-1063
    ISSN 1050-9631
    DOI 10.1002/hipo.23279
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  3. Article ; Online: Mechanisms for maintaining information in working memory.

    Stern, Chantal E / Hasselmo, Michael E

    Cognitive neuroscience

    2022  Volume 13, Issue 3-4, Page(s) 218–219

    Abstract: The review by Slotnick is valuable for raising the important question of how much the hippocampal activity induced by novel stimuli is due to mechanisms for encoding into long-term memory, and how much is due to working memory. Slotnick's paper ... ...

    Abstract The review by Slotnick is valuable for raising the important question of how much the hippocampal activity induced by novel stimuli is due to mechanisms for encoding into long-term memory, and how much is due to working memory. Slotnick's paper implicitly defines working memory as being equivalent to sustained activation during the late delay period. In this commentary, we suggest that cognitive neuroscientists should consider a broader range of cellular and synaptic mechanisms for maintaining information in working memory.
    MeSH term(s) Humans ; Memory, Short-Term/physiology ; Neuronal Plasticity/physiology ; Hippocampus/physiology
    Language English
    Publishing date 2022-10-10
    Publishing country England
    Document type Journal Article ; Research Support, N.I.H., Extramural ; Research Support, U.S. Gov't, Non-P.H.S. ; Comment
    ZDB-ID 2542443-9
    ISSN 1758-8936 ; 1758-8928
    ISSN (online) 1758-8936
    ISSN 1758-8928
    DOI 10.1080/17588928.2022.2131750
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  4. Article ; Online: Don't You Worry 'bout a Thing: Harnessing the Power of Music to Improve Emotional Health in Oncology.

    Peppercorn, Jeffrey / Miller, Earl K / Hasselmo, Michael E

    JCO oncology practice

    2023  Volume 19, Issue 12, Page(s) 1089–1091

    MeSH term(s) Humans ; Music ; Emotions ; Anxiety/therapy ; Medical Oncology
    Language English
    Publishing date 2023-10-26
    Publishing country United States
    Document type Editorial
    ZDB-ID 3028198-2
    ISSN 2688-1535 ; 2688-1527
    ISSN (online) 2688-1535
    ISSN 2688-1527
    DOI 10.1200/OP.23.00555
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  5. Article ; Online: Septo-hippocampal dynamics and the encoding of space and time.

    Robinson, Jennifer C / Wilmot, Jacob H / Hasselmo, Michael E

    Trends in neurosciences

    2023  Volume 46, Issue 9, Page(s) 712–725

    Abstract: Encoding an event in memory requires neural activity to represent multiple dimensions of behavioral experience in space and time. Recent experiments have explored the influence of neural dynamics regulated by the medial septum on the functional encoding ... ...

    Abstract Encoding an event in memory requires neural activity to represent multiple dimensions of behavioral experience in space and time. Recent experiments have explored the influence of neural dynamics regulated by the medial septum on the functional encoding of space and time by neurons in the hippocampus and associated structures. This review addresses these dynamics, focusing on the role of theta rhythm, the differential effects of septal inactivation and activation on the functional coding of space and time by individual neurons, and the influence on phase coding that appears as phase precession. We also discuss data indicating that theta rhythm plays a role in timing the internal dynamics of memory encoding and retrieval, as well as the behavioral influences of these neuronal manipulations with regard to memory function.
    MeSH term(s) Humans ; Hippocampus/physiology ; Neurons/physiology ; Theta Rhythm/physiology ; Models, Neurological ; Action Potentials/physiology
    Language English
    Publishing date 2023-07-19
    Publishing country England
    Document type Journal Article ; Review ; Research Support, U.S. Gov't, Non-P.H.S. ; Research Support, N.I.H., Extramural
    ZDB-ID 282488-7
    ISSN 1878-108X ; 0378-5912 ; 0166-2236
    ISSN (online) 1878-108X
    ISSN 0378-5912 ; 0166-2236
    DOI 10.1016/j.tins.2023.06.004
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  6. Article ; Online: Neural circuits and symbolic processing.

    Do, Quan / Hasselmo, Michael E

    Neurobiology of learning and memory

    2021  Volume 186, Page(s) 107552

    Abstract: The ability to use symbols is a defining feature of human intelligence. However, neuroscience has yet to explain the fundamental neural circuit mechanisms for flexibly representing and manipulating abstract concepts. This article will review the research ...

    Abstract The ability to use symbols is a defining feature of human intelligence. However, neuroscience has yet to explain the fundamental neural circuit mechanisms for flexibly representing and manipulating abstract concepts. This article will review the research on neural models for symbolic processing. The review first focuses on the question of how symbols could possibly be represented in neural circuits. The review then addresses how neural symbolic representations could be flexibly combined to meet a wide range of reasoning demands. Finally, the review assesses the research on program synthesis and proposes that the most flexible neural representation of symbolic processing would involve the capacity to rapidly synthesize neural operations analogous to lambda calculus to solve complex cognitive tasks.
    MeSH term(s) Brain ; Cognition ; Concept Formation ; Humans ; Learning ; Nerve Net ; Neurosciences ; Symbolism
    Language English
    Publishing date 2021-11-08
    Publishing country United States
    Document type Journal Article ; Research Support, N.I.H., Extramural ; Research Support, U.S. Gov't, Non-P.H.S. ; Review
    ZDB-ID 1223366-3
    ISSN 1095-9564 ; 1074-7427
    ISSN (online) 1095-9564
    ISSN 1074-7427
    DOI 10.1016/j.nlm.2021.107552
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  7. Article ; Online: Gated transformations from egocentric to allocentric reference frames involving retrosplenial cortex, entorhinal cortex, and hippocampus.

    Alexander, Andrew S / Robinson, Jennifer C / Stern, Chantal E / Hasselmo, Michael E

    Hippocampus

    2023  Volume 33, Issue 5, Page(s) 465–487

    Abstract: This paper reviews the recent experimental finding that neurons in behaving rodents show egocentric coding of the environment in a number of structures associated with the hippocampus. Many animals generating behavior on the basis of sensory input must ... ...

    Abstract This paper reviews the recent experimental finding that neurons in behaving rodents show egocentric coding of the environment in a number of structures associated with the hippocampus. Many animals generating behavior on the basis of sensory input must deal with the transformation of coordinates from the egocentric position of sensory input relative to the animal, into an allocentric framework concerning the position of multiple goals and objects relative to each other in the environment. Neurons in retrosplenial cortex show egocentric coding of the position of boundaries in relation to an animal. These neuronal responses are discussed in relation to existing models of the transformation from egocentric to allocentric coordinates using gain fields and a new model proposing transformations of phase coding that differ from current models. The same type of transformations could allow hierarchical representations of complex scenes. The responses in rodents are also discussed in comparison to work on coordinate transformations in humans and non-human primates.
    MeSH term(s) Animals ; Entorhinal Cortex/physiology ; Gyrus Cinguli ; Hippocampus ; Spatial Navigation/physiology ; Neurons/physiology ; Space Perception/physiology
    Language English
    Publishing date 2023-03-01
    Publishing country United States
    Document type Journal Article ; Review ; Research Support, U.S. Gov't, Non-P.H.S. ; Research Support, N.I.H., Extramural
    ZDB-ID 1074352-2
    ISSN 1098-1063 ; 1050-9631
    ISSN (online) 1098-1063
    ISSN 1050-9631
    DOI 10.1002/hipo.23513
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  8. Article ; Online: Impact of optogenetic pulse design on CA3 learning and replay: A neural model.

    Wilmerding, Lucius K / Yazdanbakhsh, Arash / Hasselmo, Michael E

    Cell reports methods

    2022  Volume 2, Issue 5, Page(s) 100208

    Abstract: Optogenetic manipulation of hippocampal circuitry is an important tool for investigating ... ...

    Abstract Optogenetic manipulation of hippocampal circuitry is an important tool for investigating learning
    MeSH term(s) Optogenetics ; Learning ; Hippocampus ; Memory ; Membrane Potentials
    Language English
    Publishing date 2022-05-03
    Publishing country United States
    Document type Journal Article ; Research Support, U.S. Gov't, Non-P.H.S. ; Research Support, N.I.H., Extramural
    ISSN 2667-2375
    ISSN (online) 2667-2375
    DOI 10.1016/j.crmeth.2022.100208
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  9. Article: Optogenetic Silencing of Medial Septal GABAergic Neurons Disrupts Grid Cell Spatial and Temporal Coding in the Medial Entorhinal Cortex.

    Robinson, Jennifer C / Ying, Johnson / Hasselmo, Michael E / Brandon, Mark P

    bioRxiv : the preprint server for biology

    2023  

    Abstract: The hippocampus and medial entorhinal cortex (MEC) form a cognitive map that facilitates spatial navigation. As part of this map, MEC grid cells fire in a repeating hexagonal pattern across an environment. This grid pattern relies on inputs from the ... ...

    Abstract The hippocampus and medial entorhinal cortex (MEC) form a cognitive map that facilitates spatial navigation. As part of this map, MEC grid cells fire in a repeating hexagonal pattern across an environment. This grid pattern relies on inputs from the medial septum (MS). The MS, and specifically its GABAergic neurons, are essential for theta rhythm oscillations in the entorhinal-hippocampal network, however, it is unknown if this subpopulation is also essential for grid cell function. To investigate this, we used optogenetics to inhibit MS-GABAergic neurons during grid cell recordings. We found that MS-GABAergic inhibition disrupted grid cell spatial periodicity both during optogenetic inhibition and during short 30-second recovery periods. Longer recovery periods of 60 seconds between the optogenetic inhibition periods allowed for the recovery of grid cell spatial firing. Grid cell temporal coding was also disrupted, as observed by a significant attenuation of theta phase precession. Together, these results demonstrate that MS-GABAergic neurons are critical for grid cell spatial and temporal coding in the MEC.
    Language English
    Publishing date 2023-11-09
    Publishing country United States
    Document type Preprint
    DOI 10.1101/2023.11.08.566228
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  10. Article ; Online: Route-dependent spatial engram tagging in mouse dentate gyrus.

    Wilmerding, Lucius K / Kondratyev, Ivan / Ramirez, Steve / Hasselmo, Michael E

    Neurobiology of learning and memory

    2023  Volume 200, Page(s) 107738

    Abstract: ... associated with learning and memory, i.e. engrams, have been labeled and manipulated to recall novel context memories ...

    Abstract The dentate gyrus (DG) of hippocampus is hypothesized to act as a pattern separator that distinguishes between similar input patterns during memory formation and retrieval. Sparse ensembles of DG cells associated with learning and memory, i.e. engrams, have been labeled and manipulated to recall novel context memories. Functional studies of DG cell activity have demonstrated the spatial specificity and stability of DG cells during navigation. To reconcile how the DG contributes to separating global context as well as individual navigational routes, we trained mice to perform a delayed-non-match-to-position (DNMP) T-maze task and labeled DG neurons during performance of this task on a novel T-maze. The following day, mice navigated a second environment: the same T-maze, the same T-maze with one route permanently blocked but still visible, or a novel open field. We found that the degree of engram reactivation across days differed based on the traversal of maze routes, such that mice traversing only one arm had higher ensemble overlap than chance but less overlap than mice running the full two-route task. Mice experiencing the open field had similar ensemble sizes to the other groups but only chance-level ensemble reactivation. Ensemble overlap differences could not be explained by behavioral variability across groups, nor did behavioral metrics correlate to degree of ensemble reactivation. Together, these results support the hypothesis that DG contributes to spatial navigation memory and that partially non-overlapping ensembles encode different routes within the context of an environment.
    MeSH term(s) Mice ; Animals ; Hippocampus/physiology ; Mental Recall/physiology ; Spatial Memory/physiology ; Neurons/physiology ; Dentate Gyrus/physiology
    Language English
    Publishing date 2023-02-21
    Publishing country United States
    Document type Journal Article ; Research Support, N.I.H., Extramural ; Research Support, U.S. Gov't, Non-P.H.S.
    ZDB-ID 1223366-3
    ISSN 1095-9564 ; 1074-7427
    ISSN (online) 1095-9564
    ISSN 1074-7427
    DOI 10.1016/j.nlm.2023.107738
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