Article
Neurosciences
Xinyi Deng, Shizhe Chen, Marielena Sosa, Mattias P. Karlsson, Xue-Xin Wei, Loren M. Frank
Summary: Humans have the ability to store and retrieve memories with various degrees of specificity. Recent research on rat hippocampal population spiking suggests that spiking during memory-associated population events is rhythmically organized and becomes more variable with experience, providing a mechanism for storing experiences with different levels of specificity.
JOURNAL OF NEUROSCIENCE
(2022)
Article
Neurosciences
Brad E. Pfeiffer
Summary: The hippocampal network does not enhance representation of the goal location during rapid spatial learning, but instead shows increased global population activity rates. However, representation of a novel goal location rapidly emerges in hippocampal ripples during brief movement pauses. These findings suggest that the hippocampus facilitates active navigation without enhanced goal representation during movement, and that goal representation in hippocampal ripples supports subsequent navigation through activation of downstream cortical networks.
JOURNAL OF NEUROSCIENCE
(2022)
Article
Multidisciplinary Sciences
Noam Nitzan, Rachel Swanson, Dietmar Schmitz, Gyorgy Buzsaki
Summary: The study found that sharp wave ripples (SPW-Rs) coincided with a transient brain-wide increase in functional connectivity, and the diversity in SPW-R features was correlated with their intrahippocampal topography along the septotemporal axis. Furthermore, variations in SPW-R features were related to the timing, sign, and magnitude of downstream responses.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2022)
Article
Multidisciplinary Sciences
Hideyoshi Igata, Yuji Ikegaya, Takuya Sasaki
Summary: During the learning process, hippocampal cell ensembles exhibit dynamic changes in replay patterns, incorporating salient locations and reward-related contexts. The directionality of replays gradually varies, including the replay of optimized paths that have never been exploited by the animals, indicating a prioritized replay of significant experiences.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2021)
Article
Neurosciences
Rong-Rong Li, Jie Yan, Hao Chen, Wei-Wei Zhang, Yu-Bo Hu, Jie Zhang, Zhi-An Hu, Yan Xiong, Zhong-Xiang Yao, Bo Hu
Summary: Sleep deprivation causes deficits in memory consolidation. This study found that hippocampal sharp wave ripple oscillations during postlearning sleep predicted the consolidation of conditioned memory. However, sleep-deprived mice showed a loss of this consolidation mechanism, leading to impaired memory. Additionally, altered spike dynamics and overexcitation of specific interneurons during recovery sleep may contribute to sleep deprivation-induced memory deficits.
Article
Multidisciplinary Sciences
Sheng-Yi Hsu, Bartosz Jura, Mau-Hsiang Shih, Pierre Meyrand, Feng-Sheng Tsai, Tiaza Bem
Summary: Evidence suggests that even after disruption of awake SWRs, spatial memory can still be learned in animal models of Alzheimer's disease, indicating that SWRs may not be crucial for memory formation in this context. Analysis using convolutional neural networks reveals that in wild-type animals, a significant amount of learning-related information is contained in SWRs and signals generated near them, while this information is limited in Alzheimer's disease models.
SCIENTIFIC REPORTS
(2021)
Article
Neurosciences
Emma L. Krause, Jan Drugowitsch
Summary: This study finds that awake hippocampal sharp-wave ripples (SWRs) can simulate trajectories with momentum, while replay events during sleep lack this momentum. Previous analysis of replayed trajectories for navigational planning was biased by the heuristic SWR sub-selection.
Article
Multidisciplinary Sciences
Yiyao Zhang, Liang Cao, Viktor Varga, Miao Jing, Mursel Karadas, Yulong Li, Gyorgy Buzsaki
Summary: In mice, cholinergic signaling in the hippocampus increased in parallel with theta/gamma power during walking and REM sleep, while reaching its minimum during hippocampal sharp-wave ripples (SPW-R). Memory performance was impaired when medial septal cholinergic neurons were selectively optogenetically stimulated in a delay area. This stimulation also decreased the incidence of SPW-Rs.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2021)
Article
Neurosciences
George Trompoukis, Leonidas J. Leontiadis, Pavlos Rigas, Costas Papatheodoropoulos
Summary: The functional organization of the hippocampus along its longitudinal axis shows significant heterogeneity. Development of sharp wave and ripples (SPW-Rs) varies between the ventral and dorsal hippocampus, with the ventral hippocampus showing more gradual development. Changes in local network excitability and inhibition play a significant role in the generation of SPW-Rs, particularly in the ventral hippocampus.
Article
Multidisciplinary Sciences
Elliott Wimmer, Yunzhe Liu, Daniel C. McNamee, Raymond J. Dolan
Summary: Theories of neural replay propose that it supports various functions, mainly planning and memory consolidation. This study tests the hypothesis that different signatures of replay in the same task are related to model-based decision-making and memory preservation. Using magnetoencephalography and multivariate analysis, the researchers identify temporally compressed sequential reactivation, or replay, before choice and following reward feedback. The results support key theoretical proposals regarding the functional role of replay and demonstrate the modulation of planning and memory-related signals by ongoing computational and task demands.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2023)
Article
Multidisciplinary Sciences
Hefei Guan, Steven J. Middleton, Takafumi Inoue, Thomas J. McHugh
Summary: The bilateral projection from CA3 plays a key role in coordinating CA1 spatial coding across hemispheres. Blocking synaptic transmission at CA3 terminals leads to decreased ripple synchronization between left and right CA1, and results in less coordinated neuronal ensemble activity across hemispheres during exploration and rest.
NATURE COMMUNICATIONS
(2021)
Article
Neurosciences
Enrique R. Sebastian, Juan P. Quintanilla, Alberto Sanchez-Aguilera, Julio Esparza, Elena Cid, Liset M. de la Prida
Summary: In this study, the authors used topological and dimensionality reduction techniques to analyze the waveform of ripples recorded in the hippocampus. They found that the waveforms distribute in a low-dimensional space, conveying information about the underlying synaptic inputs. The study also revealed variations in ripple waveforms during wakefulness, sleep, and learning.
NATURE NEUROSCIENCE
(2023)
Editorial Material
Biochemistry & Molecular Biology
Matthew F. Nolan
Summary: A new study reveals that neurons in the medial entorhinal cortex synchronize with hippocampal replay events during learning, suggesting a potential mechanism for the consolidation of spatial memories.
Article
Neurosciences
Peter M. Klein, Vipan K. Parihar, Gergely G. Szabo, Miklos Zoldi, Maria C. Angulo, Barrett D. Allen, Amal N. Amin, Quynh-Anh Nguyen, Istvan Katona, Janet E. Baulch, Charles L. Limoli, Ivan Soltesz
Summary: Research shows that space-relevant doses of mixed-ion GCR preferentially alter hippocampal inhibitory neurotransmission, leading to disruptions in the local field potentials of hippocampal oscillations, ultimately affecting learning, memory, and anxiety behavior.
NEUROBIOLOGY OF DISEASE
(2021)
Review
Neurosciences
Boxu Xie, Zhihang Zhen, Ouyang Guo, Heming Li, Moran Guo, Junli Zhen
Summary: Sharp wave ripples (SWRs) are high-frequency synchronization events generated by hippocampal neuronal circuits and are crucial for the consolidation of spatial, episodic, and social memories. SWRs originate from hippocampal CA3 and subiculum and modulate neuronal activity in cortical and subcortical regions. Different hippocampal subregions have distinct functions in learning and memory, and SWR dysregulation can contribute to cognitive impairments in neurodegenerative and neurodevelopmental diseases.
BRAIN RESEARCH BULLETIN
(2023)
Article
Neuroimaging
Elizabeth R. Spencer, Dhinakaran Chinappen, Britt C. Emerton, Amy K. Morgan, Matti S. Hamalainen, Dara S. Manoach, Uri T. Eden, Mark A. Kramer, Catherine J. Chu
Summary: Rolandic epilepsy is a common form of epileptic encephalopathy characterized by sleep-potentiated inferior Rolandic epileptiform spikes, seizures, and cognitive deficits in school-age children that resolve by adolescence. Recent research suggests that there is a lack of sleep spindles, which are thalamocortical rhythms associated with sleep-dependent learning, in the Rolandic cortex during active epilepsy. This disruption in spindle activity extends beyond the epileptic cortex and may contribute to the broad cognitive deficits observed in this condition.
NEUROIMAGE-CLINICAL
(2022)
Article
Engineering, Biomedical
Ishita Basu, Ali Yousefi, Britni Crocker, Rina Zelmann, Angelique C. Paulk, Noam Peled, Kristen K. Ellard, Daniel S. Weisholtz, G. Rees Cosgrove, Thilo Deckersbach, Uri T. Eden, Emad N. Eskandar, Darin D. Dougherty, Sydney S. Cash, Alik S. Widge
Summary: This study demonstrates that closed-loop electrical stimulation of the internal capsule can enhance cognitive control in participants with epilepsy. Decoding of task performance from electrode activity was also achieved. These findings have the potential to improve cognitive deficits in individuals with severe mental disorders.
NATURE BIOMEDICAL ENGINEERING
(2023)
Article
Neurosciences
Xinyi Deng, Shizhe Chen, Marielena Sosa, Mattias P. Karlsson, Xue-Xin Wei, Loren M. Frank
Summary: Humans have the ability to store and retrieve memories with various degrees of specificity. Recent research on rat hippocampal population spiking suggests that spiking during memory-associated population events is rhythmically organized and becomes more variable with experience, providing a mechanism for storing experiences with different levels of specificity.
JOURNAL OF NEUROSCIENCE
(2022)
Article
Computer Science, Artificial Intelligence
Mohammad R. Rezaei, Alex E. Hadjinicolaou, Sydney S. Cash, Uri T. Eden, Ali Yousefi
Summary: With the development of neural recording technology, research in integrative neuroscience relies on scalable and computationally tractable data analysis methods. Latent process models have shown promise in estimating cognitive processes, but scaling them to high-dimensional neural recordings remains challenging. In this paper, a novel direct discriminative decoder (DDD) model is introduced, which can estimate cognitive process dynamics without requiring precise receptive field models of individual neurons or brain nodes.
NEURAL COMPUTATION
(2022)
Article
Cell Biology
David B. Kastner, Eric A. Miller, Zhuonan Yang, Demetris K. Roumis, Daniel F. Liu, Loren M. Frank, Peter Dayan
Summary: Understanding the complexities of behavior is crucial for interpreting neurophysiological data and establishing animal models of neuropsychiatric disease. In this study, we explored multiple processes contributing to behavior in rats, revealing their reliance on spatial preferences and memory in learning a spatial alternation task. Our approach also distinguished between learning based on established preferences and generalization of task structure.
Article
Clinical Neurology
Shuqiang Chen, Susan Redline, Uri T. Eden, Michael J. Prerau
Summary: This study develops a statistical modeling framework based on point process theory to characterize the moment-to-moment rate of occurrence of respiratory events in obstructive sleep apnea. The results provide new insights into the temporal dynamics of respiratory events and reveal significant differences in event patterns among gender, age, and race/ethnicity groups.
Review
Biology
Alison E. Comrie, Loren M. Frank, Kenneth Kay
Summary: This article discusses the importance of imagination as a biological function and its relationship with the hippocampus in the brain. It highlights recent findings that suggest the hippocampus plays a fundamental role in generating hypothetical experiences and thoughts, beyond traditional views of its function in memory and spatial navigation. The article suggests that the hippocampus contributes to a wider range of cognitive abilities than previously thought.
PHILOSOPHICAL TRANSACTIONS OF THE ROYAL SOCIETY B-BIOLOGICAL SCIENCES
(2022)
Review
Multidisciplinary Sciences
Anli A. Liu, Simon Henin, Saman Abbaspoor, Anatol Bragin, Elizabeth A. Buffalo, Jordan S. Farrell, David J. Foster, Loren M. Frank, Tamara Gedankien, Jean Gotman, Jennifer A. Guidera, Kari L. Hoffman, Joshua Jacobs, Michael J. Kahana, Lin Li, Zhenrui Liao, Jack J. Lin, Attila Losonczy, Rafael Malach, Matthijs A. van der Meer, Kathryn McClain, Bruce L. McNaughton, Yitzhak Norman, Andrea Navas-Olive, Liset M. de la Prida, Jon W. Rueckemann, John J. Sakon, Ivan Skelin, Ivan Soltesz, Bernhard P. Staresina, Shennan A. Weiss, Matthew A. Wilson, Kareem A. Zaghloul, Michael Zugaro, Gyorgy Buzsaki
Summary: This article discusses the methodological challenges in detecting, analyzing, and reporting Sharp Wave Ripples, and suggests practical solutions to distinguish them from other high-frequency events. It emphasizes the importance of establishing shared experimental, detection, and reporting standards.
NATURE COMMUNICATIONS
(2022)
Article
Biology
Oliver Rubel, Andrew Tritt, Ryan Ly, Benjamin K. Dichter, Satrajit Ghosh, Lawrence Niu, Pamela Baker, Ivan Soltesz, Lydia Ng, Karel Svoboda, Loren Frank, Kristofer E. Bouchard
Summary: This article introduces the design and implementation principles of a language for neurophysiology data and demonstrates the impact of NWB software in unifying the description of neurophysiology data across different species, enabling the reproducibility, interchangeability, and reusability of the data.
Article
Engineering, Biomedical
Zhengtuo Zhao, Hanlin Zhu, Xue Li, Liuyang Sun, Fei He, Jason E. Chung, Daniel F. Liu, Loren Frank, Lan Luan, Chong Xie
Summary: Penetrating flexible electrode arrays enable long-term stable electrophysiological recordings and inference of patterns of neural information flow.
NATURE BIOMEDICAL ENGINEERING
(2023)
Article
Multidisciplinary Sciences
Abhilasha Joshi, Eric L. Denovellis, Abhijith Mankili, Yagiz Meneksedag, Thomas J. Davidson, Anna K. Gillespie, Jennifer A. Guidera, Demetris Roumis, Loren M. Frank
Summary: The hippocampus expresses spatial representations and is crucial for navigation, while the details of locomotor processes are primarily computed and represented in subcortical circuits. This study found a coordination between hippocampal spatial representations and the forelimb stepping cycle in freely behaving rats, with precise timing during spatial decisions.
Article
Neurosciences
Timothy A. Krausz, Alison E. Comrie, Ari E. Kahn, Loren M. Frank, Nathaniel D. Daw, Joshua D. Berke
Summary: Animals make decisions based on future rewards and the brain uses multiple learning algorithms to update place values.
Review
Genetics & Heredity
Hussam Al-Kateb, P. Y. Billie Au, Siren Berland, Benjamin Cogne, Florence Demurger, Joel Fluss, Bertrand Isidor, L. Matthew Frank, Konstantinos Varvagiannis, David A. Koolen, Marie McDonald, Sarah Montgomery, Stephanie Moortgat, Marie Deprez, Deniz Karadurmus, Julie Paulsen, Andre Reis, Melissa Rieger, Georgia Vasileiou, Marcia Willing, Marwan Shinawi
Summary: Calmodulin-binding transcriptional activator 1 (CAMTA1) is highly expressed in the brain and plays a crucial role in cell cycle regulation, cell differentiation, long-term memory regulation, and the development and survival of cerebellar neurons. This study characterized a large cohort of individuals with novel CAMTA1 variants, identifying a range of phenotypic findings such as developmental delay, unsteady gait, hypotonia, behavioral problems, and eye abnormalities. Additionally, the study found a high incidence of dysarthria, dysgraphia, microcephaly, gastrointestinal abnormalities, sleep difficulties, and nonspecific brain MRI findings. The findings highlight reduced penetrance and variable expressivity of the variants and provide valuable information for counseling and management of individuals with CAMTA1 variants.