Hippocampus最新文献

{"title":"Issue Information - Editorial Board","authors":"","doi":"10.1002/hipo.23565","DOIUrl":"https://doi.org/10.1002/hipo.23565","url":null,"abstract":"","PeriodicalId":13171,"journal":{"name":"Hippocampus","volume":"34 12","pages":"673"},"PeriodicalIF":2.4,"publicationDate":"2024-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/hipo.23565","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142664708","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Supramammillary Theta Oscillations in Water Maze Learning","authors":"Calvin K. Young,&nbsp;Ming Ruan,&nbsp;Neil McNaughton","doi":"10.1002/hipo.23646","DOIUrl":"10.1002/hipo.23646","url":null,"abstract":"<div>\u0000 \u0000 <p>The supramammillary nucleus (SuM) in the hypothalamus, in conjunction with the hippocampus (HPC), has been implicated through theta oscillations in various brain functions ranging from locomotion to learning and memory. While the indispensable role of the SuM in HPC theta generation in anesthetized animals is well-characterized, the SuM is not always necessary for HPC theta in awake animals. This raises questions on the precise behavioral relevance of SuM theta activity and its interaction with HPC theta activity. We used simultaneously recorded SuM and HPC local field potentials (LFPs) in a one-day water maze (WM) learning paradigm in rats (<i>n</i> = 8), to show that theta activities recorded from the SuM itself were not positively correlated with locomotor (swimming) speed nor acceleration, but the individual relationship between acceleration and SuM theta frequency is correlated with WM learning rates. In contrast, we found that SuM-HPC theta phase coherence is strongly correlated with swimming speed and acceleration, but these do not relate to WM learning. SuM-HPC-directed coherence analysis demonstrated no swimming kinetics nor learning rate associations, but revealed that periods of high SuM-HPC theta phase coherence are driven by the SuM at relatively low (~6.2 Hz) frequencies. Additionally, we demonstrate that the SuM and the HPC also engage in non-random, non-coherent phase coupling modes where either structure preferentially displays a ± 2 Hz difference with the other. Our data indicate SuM theta LFPs do not appear to be related to either speed coding or spatial learning in swimming rats and display non-random out-of-phase theta frequency coupling with the HPC.</p>\u0000 </div>","PeriodicalId":13171,"journal":{"name":"Hippocampus","volume":"34 12","pages":"767-776"},"PeriodicalIF":2.4,"publicationDate":"2024-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142582766","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Dissecting the Hippocampal Regulation of Approach-Avoidance Conflict: Integrative Perspectives From Optogenetics, Stress Response, and Epigenetics","authors":"C. Forastieri,&nbsp;E. Romito,&nbsp;A. Paplekaj,&nbsp;E. Battaglioli,&nbsp;F. Rusconi","doi":"10.1002/hipo.23647","DOIUrl":"10.1002/hipo.23647","url":null,"abstract":"<p>Psychiatric disorders are multifactorial conditions without clear biomarkers, influenced by genetic, environmental, and developmental factors. Understanding these disorders requires identifying specific endophenotypes that help break down their complexity. Here, we undertake an in-depth analysis of one such endophenotype, namely imbalanced approach-avoidance conflict (AAC), reviewing its significant dependency on the hippocampus. Imbalanced AAC is a transdiagnostic endophenotype, being a feature of many psychiatric conditions in humans. However, it is predominantly examined in preclinical research through paradigms that subject rodents to conflict-laden scenarios. This review offers an original perspective by discussing the AAC through three distinct lights: optogenetic modulation of the AAC, which updates our understanding of the hippocampal contribution to behavioral inhibition; the impact of environmental stress, which exacerbates conflict and strengthens the stress-psychopathology axis; and inherent epigenetic aspects, which uncover crucial molecular underpinnings of environmental (mal) adaptation. By integrating these perspectives, in this review we aim to underline a cross-species causal nexus between heightened hippocampal activity and avoidance behavior. In addition, we suggest a rationale to explore epigenetic pharmacology as a potential strategy to tackle AAC-related psychopathology. This review assumes greater significance when viewed through the lens of advancing AAC-centric diagnostics in human subjects. Unlike traditional questionnaires, which struggle to accurately measure individual differences in AAC-related dimensions, new approaches using virtual reality and computer games show promise in better focusing the magnitude of AAC contribution to psychopathology.</p>","PeriodicalId":13171,"journal":{"name":"Hippocampus","volume":"34 12","pages":"753-766"},"PeriodicalIF":2.4,"publicationDate":"2024-11-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/hipo.23647","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142567961","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Distinct Ventral Hippocampus Network Properties in Dissociated Cultures","authors":"Menahem Segal","doi":"10.1002/hipo.23648","DOIUrl":"10.1002/hipo.23648","url":null,"abstract":"<p>Extensive research has been focused in the past century on structural, physiological, and molecular attributes of the hippocampus. This interest was created by the unique involvement of the hippocampus in cognitive and affective functions of the brain. Functional analysis revealed that the hippocampus has divergent properties along its axial dimension to the extent that the dorsal sector (dorsal hippocampus, DH) has different connections with the rest of the brain than those of the ventral sector (VH). Still, longitudinal pathways connect the DH with the VH and dampen the functional differences between the sectors. To be able to identify the intrinsic functional difference between the DH and VH, we produced dissociated monolayer cultures from prenatal DH and VH and examined their properties at 10–20 days after plating by imaging the spontaneous activity of the network using Fluo-2 AM, a calcium indicator. Surprisingly, while DH and VH sectors produced dissociated cultures with similar morphological attributes, VH cultures were more active spontaneously than DH cultures. Furthermore, when stimulated to produce action potentials, VH neurons triggered network bursts in postsynaptic neurons more often than DH cultures. Finally, in both DH and VH cultures, electrical stimulation of single cells produced network bursts in response to a burst of action potentials rather than to single spikes. These experiments indicate that even in dissociated cultures, neurons of the VH are more excitable and sensitive to electrical stimulation than DH; hence, they are more likely to generate network bursts and epileptic seizures, as suggested for in vivo brains.</p>","PeriodicalId":13171,"journal":{"name":"Hippocampus","volume":"34 12","pages":"744-752"},"PeriodicalIF":2.4,"publicationDate":"2024-11-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/hipo.23648","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142564378","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Egr1 Expression Is Correlated With Synaptic Activity but Not Intrinsic Membrane Properties in Mouse Adult-Born Dentate Granule Cells","authors":"Shane M. Ohline,&nbsp;Barbara J. Logan,&nbsp;Stephanie M. Hughes,&nbsp;Wickliffe C. Abraham","doi":"10.1002/hipo.23644","DOIUrl":"10.1002/hipo.23644","url":null,"abstract":"<p>The discovery of adult-born granule cells (aDGCs) in the dentate gyrus of the hippocampus has raised questions regarding how they develop, incorporate into the hippocampal circuitry, and contribute to learning and memory. Here, we used patch-clamp electrophysiology to investigate the intrinsic and synaptic excitability of mouse aDGCs as they matured, enabled by using a tamoxifen-induced genetic label to birth date the aDGCs at different animal ages. Importantly, we also undertook immunofluorescence studies of the expression of the immediate early gene Egr1 and compared these findings with the electrophysiology data in the same animals. We examined two groups of animals, with aDGC birthdating when the mice were 2 months and at 7–9 months of age. In both groups, cells 4 weeks old had lower thresholds for current-evoked action potentials than older cells but fired fewer spikes during long current pulses and responded more poorly to synaptic activation. aDGCs born in both 2 and 7–9-month-old mice matured in their intrinsic excitability and synaptic properties from 4–12 weeks postgenesis, but this occurred more slowly for the older age animals. Interestingly, this pattern of intrinsic excitability changes did not correlate with the pattern of Egr1 expression. Instead, the development of Egr1 expression was correlated with the frequency of spontaneous excitatory postsynaptic currents. These results suggest that in order for aDGCs to fully participate in hippocampal circuitry, as indicated by Egr1 expression, they must have developed enough synaptic input, in spite of the greater input resistance and reduced firing threshold that characterizes young aDGCs.</p>","PeriodicalId":13171,"journal":{"name":"Hippocampus","volume":"34 12","pages":"729-743"},"PeriodicalIF":2.4,"publicationDate":"2024-10-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/hipo.23644","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142464141","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Adult Neurogenesis and the Initiation of Social Aggression in Male Mice","authors":"Mumeko C. Tsuda,&nbsp;Talia Akoh-Arrey,&nbsp;Jeffrey C. Mercurio,&nbsp;Ariana Rucker,&nbsp;Megan L. Airey,&nbsp;Hannah Jacobs,&nbsp;Daria Lukasz,&nbsp;Lijing Wang,&nbsp;Heather A. Cameron","doi":"10.1002/hipo.23643","DOIUrl":"10.1002/hipo.23643","url":null,"abstract":"<p>The hippocampus is important for social behavior and exhibits unusual structural plasticity in the form of continued production of new granule neurons throughout adulthood, but it is unclear how adult neurogenesis contributes to social interactions. In the present study, we suppressed neurogenesis using a pharmacogenetic mouse model and examined social investigation and aggression in adult male mice to investigate the role of hippocampal adult-born neurons in the expression of aggressive behavior. In simultaneous choice tests with stimulus mice placed in corrals, mice with complete suppression of adult neurogenesis in adulthood (TK mice) exhibited normal social investigation behaviors, indicating that new neurons are not required for social interest, social memory, or detection of and response to social olfactory signals. However, mice with suppressed neurogenesis displayed decreased offensive and defensive aggression in a resident-intruder paradigm, and less resistance in a social dominance test, relative to neurogenesis-intact controls, when paired with weight and strain-matched (CD-1) mice. During aggression tests, TK mice were frequently attacked by the CD-1 intruder mice, which never occurred with WTs, and normal CD-1 male mice investigated TK mice less than controls when corralled in the social investigation test. Importantly, TK mice showed normal aggression toward prey (crickets) and smaller, nonaggressive (olfactory bulbectomized) C57BL/6J intruders, suggesting that mice lacking adult neurogenesis do not avoid aggressive social interactions if they are much larger than their opponent and will clearly win. Taken together, our findings show that adult hippocampal neurogenesis plays an important role in the instigation of intermale aggression, possibly by weighting a cost–benefit analysis against confrontation in cases where the outcome of the fight is not clear.</p>","PeriodicalId":13171,"journal":{"name":"Hippocampus","volume":"34 12","pages":"711-728"},"PeriodicalIF":2.4,"publicationDate":"2024-10-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/hipo.23643","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142390201","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Flexible Behavioral Adjustment to Frustrative Nonreward in Anticipatory Behavior, but Not in Consummatory Behavior, Requires the Dorsal Hippocampus","authors":"Christopher Hagen,&nbsp;Megi Hoxha,&nbsp;Saee Chitale,&nbsp;Andre O. White,&nbsp;Pedro M. Ogallar,&nbsp;Alejandro N. Expósito,&nbsp;Antonio D. R. Agüera,&nbsp;Carmen Torres,&nbsp;Mauricio R. Papini,&nbsp;Marta Sabariego","doi":"10.1002/hipo.23642","DOIUrl":"10.1002/hipo.23642","url":null,"abstract":"<div>\u0000 \u0000 <p>The hippocampus (HC) is recognized for its pivotal role in memory-related plasticity and facilitating adaptive behavioral responses to reward shifts. However, the nature of its involvement in the response to reward downshifts remains to be determined. To bridge this knowledge gap, we explored the HC's function through a series of experiments in various tasks involving reward downshifts and using several neural manipulations in rats. In Experiment 1, complete excitotoxic lesions of the HC impaired choice performance in a modified T-maze after reducing the quantity of sugar pellet rewards. In Experiment 2, chemogenetic inhibition of the dorsal HC (dHC) disrupted anticipatory behavior following a food-pellet reward reduction. Experiments 3–5 impaired HC function by using peripheral lipopolysaccharide (LPS) administration. This treatment, which induces peripheral inflammation affecting HC function, significantly increased cytokine levels in the dHC (Experiment 3) and impaired anticipatory choice behavior (Experiment 4). None of these dorsal hippocampal manipulations affected consummatory responses in animals experiencing sucrose downshifts. Accordingly, we found no evidence of increased neural activation in either the dorsal or ventral HC, as measured by c-Fos expression, after a sucrose downshift task involving consummatory suppression (Experiment 6). The results highlight the HC's pivotal role in adaptively modulating anticipatory behavior in response to a variety of situations involving frustrative nonreward, while having no effect on adjustments on consummatory behavior. The data supporting this conclusion were obtained under heterogeneous experimental conditions derived from a multi-laboratory collaboration, ensuring the robustness and high reproducibility of our findings. Spatial orientation, memory update, choice of reward signals of different values, and anticipatory versus consummatory adjustments to reward downshift are discussed as potential mechanisms that could account for the specific effects observed from HC manipulations.</p>\u0000 </div>","PeriodicalId":13171,"journal":{"name":"Hippocampus","volume":"34 12","pages":"688-710"},"PeriodicalIF":2.4,"publicationDate":"2024-10-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142380711","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Comparable Theta Phase Coding Dynamics Along the Transverse Axis of CA1","authors":"Aditi Bishnoi,&nbsp;Sachin S. Deshmukh","doi":"10.1002/hipo.23641","DOIUrl":"10.1002/hipo.23641","url":null,"abstract":"<div>\u0000 \u0000 <p>Topographical projection patterns from the entorhinal cortex to area CA1 of the hippocampus have led to a hypothesis that proximal CA1 (pCA1, closer to CA2) is spatially more selective than distal CA1 (dCA1, closer to the subiculum). While earlier studies have shown evidence supporting this hypothesis, we recently showed that this difference does not hold true under all experimental conditions. In a complex environment with distinct local texture cues on a circular track and global visual cues, pCA1 and dCA1 display comparable spatial selectivity. Correlated with the spatial selectivity differences, the earlier studies also showed differences in theta phase coding dynamics between pCA1 and dCA1 neurons. Here we show that there are no differences in theta phase coding dynamics between neurons in these two regions under the experimental conditions where pCA1 and dCA1 neurons are equally spatially selective. These findings challenge the established notion of dCA1 being inherently less spatially selective and theta modulated than pCA1 and suggest further experiments to understand theta-mediated activation of the CA1 sub-networks to represent space.</p>\u0000 </div>","PeriodicalId":13171,"journal":{"name":"Hippocampus","volume":"34 12","pages":"674-687"},"PeriodicalIF":2.4,"publicationDate":"2024-10-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142377816","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}