Article
Multidisciplinary Sciences
Sanne Beerens, Rozan Vroman, Jack F. Webster, Christian Wozny
Summary: The hippocampal formation is anatomically and functionally divided into a dorsal and a ventral part involved in processing cognitive tasks and emotional stimuli, respectively. While the ventral subiculum projects to the medial prefrontal cortex, the dorsal subiculum targets the anterior cingulate cortex and other areas of the prefrontal cortex with both excitatory and inhibitory neurons. These novel connections challenge existing anatomical data and refine the hippocampocortical wiring diagram.
Article
Multidisciplinary Sciences
Balint Kiraly, Andor Domonkos, Marta Jelitai, Vitor Lopes-dos-Santos, Sergio Martinez-Bellver, Barnabas Kocsis, Daniel Schlingloff, Abhilasha Joshi, Minas Salib, Richard Fiath, Peter Bartho, Istvan Ulbert, Tamas F. Freund, Tim J. Viney, David Dupret, Viktor Varga, Balazs Hangya
Summary: The medial septum orchestrates hippocampal network activity at multiple temporal scales likely mediating memory encoding and retrieval.
NATURE COMMUNICATIONS
(2023)
Article
Neurosciences
Alexander R. Callan, Martin Hess, Felix Felmy, Christian Leibold
Summary: Researchers have found that neurons in the medial superior olive (MSO) have highly integrated synaptic inputs on their dendrites, enabling secure transmission through coordinated release of neurotransmitters at multiple independent active zones. The anatomical arrangement increases the amplitude and sharpens the time course of excitatory postsynaptic potentials, leading to improved binaural coincidence detection compared with single large synapses at the soma.
JOURNAL OF NEUROSCIENCE
(2021)
Article
Neurosciences
Weronika Szadzinska, Konrad Danielewski, Kacper Kondrakiewicz, Karolina Andraka, Evgeni Nikolaev, Marta Mikosz, Ewelina Knapska
Summary: Fear extinction training gradually changes the vHIP-PL connectivity, allowing for fear suppression. In the absence of fear suppression from the vHIP, signals from the BL play a dominant role, resulting in heightened fear levels.
JOURNAL OF NEUROSCIENCE
(2021)
Article
Neurosciences
Yarmo Mackenbach, J. Gerard G. Borst
Summary: The medial superior olive (MSO) is a specialized binaural nucleus that detects the relative arrival times of sounds at both ears. Excitatory inputs to MSO neurons from different ears are segregated to different dendrites, and the neurons can phase-lock to multiple tones within a stimulus. The ability to phase-lock is linearly related to the size of the subthreshold response.
JOURNAL OF NEUROSCIENCE
(2023)
Editorial Material
Neurosciences
Vincent Robert, Tanvi Butola, Jayeeta Basu
Summary: Synchronized activity, a characteristic feature of hippocampal network dynamics, is present early in development. The role of extrinsic inputs in driving this activity is still unknown. In a study published in Neuron, Leprince et al. demonstrate that while synchronized activity in the hippocampus is modulated by both cortical and thalamic inputs ex vivo, it is solely dependent on cortical inputs in vivo.
Article
Cell Biology
Michele Nardin, Karola Kaefer, Federico Stella, Jozsef Csicsvari
Summary: This study investigated the circuit mechanism of neuronal assembly interactions between the hippocampus and the medial prefrontal cortex (mPFC) in adult rats during a rule-switching task. The results revealed functionally coupled CA1-mPFC cells that synchronized their activity beyond spatial coding or oscillatory firing. These functionally connected cells formed interconnected assemblies, and the upregulated theta oscillatory firing of mPFC cells enabled transient interactions with specific CA1 assemblies for distributed computations.
Article
Biochemistry & Molecular Biology
Yann S. Mineur, Tenna N. Mose, Laura Vanopdenbosch, Ian M. Etherington, Chika Ogbejesi, Ashraful Islam, Cristiana M. Pineda, Richard B. Crouse, Wenliang Zhou, David C. Thompson, Matthew P. Bentham, Marina R. Picciotto
Summary: Acetylcholine (ACh) levels are elevated in depressed individuals. Blocking ACh receptors can have antidepressant effects and decrease stress-related behaviors. ACh levels increase in response to stress, while blocking the enzyme that degrades ACh induces depression-like symptoms. Cholinergic inputs from the medial septum/diagonal bands of Broca (MSDBB) or ChAT-positive neurons intrinsic to the hippocampus mediate stress-related behaviors in mice.
MOLECULAR PSYCHIATRY
(2022)
Article
Neurosciences
Marissa C. Applegate, Konstantin S. Gutnichenko, Dmitriy Aronov
Summary: The mammalian hippocampal formation is organized based on different functions and inputs. These inputs contribute to the organization along the long axis and the transverse axis of the hippocampus. In this study, retrograde tracing was used to map the inputs into the hippocampal formation of a food-caching bird, the black-capped chickadee. The results revealed unique patterns of inputs, similar to those observed in mammals, highlighting the anatomical similarities across distantly related species.
JOURNAL OF COMPARATIVE NEUROLOGY
(2023)
Article
Cell Biology
Olesia M. Bilash, Spyridon Chavlis, Cara D. Johnson, Panayiota Poirazi, Jayeeta Basu
Summary: The lateral entorhinal cortex (LEC) is responsible for providing multisensory information to the hippocampus, aiding in the processing and coding of episodic memory. However, little is known about the functional circuit interactions between the LEC and the hippocampus. Through functional circuit mapping and computational modeling, this study reveals that long-range glutamatergic LEC projections can modulate excitation-inhibition dynamics in CA1 pyramidal neurons, involving the recruitment of VIP and CCK interneurons. These findings highlight a cortically driven GABAergic microcircuit mechanism that regulates dendritic computations and supports compartment-specific coding in the hippocampus.
Article
Biology
Tanja Fuchsberger, Claudia Clopath, Przemyslaw Jarzebowski, Zuzanna Brzosko, Hongbing Wang, Ole Paulsen
Summary: The study suggests that dopamine can induce input-specific long-term potentiation in hippocampal synapses, affecting memory connections between neurons. This mechanism can control memory allocation and enable different types of reinforcement learning, while also enhancing the activation strength and spatial information carrying capacity of reactivated neurons.
Article
Neurosciences
Wei Liu, Yingjie Shi, James N. Cousins, Nils Kohn, Guillen Fernandez
Summary: Research indicates that successfully remembered events are associated with distinct activation patterns in the hippocampus and medial prefrontal cortex, while similar connectivity patterns between events are linked to memory formation and retention of order. Different activation patterns represent neural segmentation of events, while similar connectivity patterns encode context information to integrate events into a narrative.
Article
Cell Biology
Barnabas Kocsis, Sergio Martinez-Bellver, Richard Fiath, Andor Domonkos, Katalin Sviatko, Daniel Schlingloff, Peter Bartho, Tamas F. Freund, Istvan Ulbert, Szabolcs Kali, Viktor Varga, Balazs Hangya
Summary: Episodic learning and memory retrieval are dependent on the GABAergic network of the medial septum, which achieves theta synchrony through synchronization of pacemakers and glutamatergic neurons. These findings provide experimental and theoretical support for a frequency-synchronization mechanism for pacing hippocampal theta.
Article
Biochemistry & Molecular Biology
Greer S. Kirshenbaum, Chia-Yuan Chang, Maria Bompolaki, Victoria R. Bradford, Joseph Bell, Stylianos Kosmidis, Rebecca M. Shansky, Javier Orlandi, Lisa M. Savage, Alexander Z. Harris, E. David Leonardo, Alex Dranovsky
Summary: Adult neurogenesis is reduced during aging and impaired in stress, memory, and cognition disorders, but its normal function is still unclear. This study found that long-term suppression of neurogenesis led to a decline in hippocampal acetylcholine signaling and working memory deficits. However, compensatory reorganization of the cholinergic dentate gyrus inputs and recruitment of different neuronal projections helped correct the memory dysfunction. These findings highlight the importance of hippocampal neurogenesis in memory maintenance and provide insights into the progressive nature of memory deterioration.
MOLECULAR PSYCHIATRY
(2023)
Article
Anatomy & Morphology
Rosendo G. Hernandez, Beatriz Benitez-Temino, Rosa R. de la Cruz, Angel M. Pastor
Summary: In this study, the discharge activity of premotor neurons and eye movements were recorded simultaneously in a chronic cat preparation. The results showed that ABD Ints had a high correlation with eye movements, exhibiting sensitivity to eye position and velocity. ATD neurons also discharged in relation to eye movements but with lower sensitivity. Interestingly, ATD neurons had a lower recruitment threshold compared to ABD Ints and played a significant role in facilitating ABD Int signal transmission onto medial rectus motoneurons.
BRAIN STRUCTURE & FUNCTION
(2023)
Article
Biochemistry & Molecular Biology
Daniela Couto, Deolinda Santinha, Tania Melo, Emanuel Ferreira-Fernandes, Romeu A. Videira, Ana Campos, Margarida Fardilha, Pedro Domingues, M. Rosario M. Domingues
CHEMISTRY AND PHYSICS OF LIPIDS
(2015)
Review
Neurosciences
Matthew A. Wilson, Carmen Varela, Miguel Remondes
CURRENT OPINION IN NEUROBIOLOGY
(2015)
Article
Cell Biology
Miguel Remondes, Matthew A. Wilson
Article
Neurosciences
Li Liang, Stefan N. Oline, Justin C. Kirk, Lukas Ian Schmitt, Robert W. Komorowski, Miguel Remondes, Michael M. Halassa
FRONTIERS IN NEURAL CIRCUITS
(2017)
Article
Biochemistry & Molecular Biology
Emanuel Ferreira-Fernandes, Sara L. C. Esteves, Luis Korrodi-Gregorio, Georg Luers, Vera Afreixo, Margarida Fardilha, Odete A. B. da Cruz e Silva
JOURNAL OF MOLECULAR NEUROSCIENCE
(2015)
Correction
Neurosciences
Miguel Remondes, Matthew A. Wilson
Article
Biochemical Research Methods
Deolinda Santinha, Emanuel Ferreira-Fernandes, Tania Melo, Eduarda M. P. Silva, Elisabete Maciel, Margarida Fardilha, Pedro Domingues, M. Rosario M. Domingues
RAPID COMMUNICATIONS IN MASS SPECTROMETRY
(2014)
Article
Environmental Sciences
Marcos Mateus, Miguel Remondes, Ligia Pinto, Alexandra Silva
FRONTIERS IN MARINE SCIENCE
(2021)
Article
Neurosciences
Marcelo Dias, Ines Marques-Morgado, Joana E. Coelho, Pedro Ruivo, Luisa Lopes, Miguel Remondes
Summary: A new method for transection and retraction of the superior sagittal sinus in rats is described, enabling direct access to brain areas previously obstructed by the sinus, without causing hemorrhage or adverse consequences.
Article
Neurosciences
Marcelo Dias, Raquel Ferreira, Miguel Remondes
Summary: The study reveals the crucial role of MEC excitatory neurons in timing behavior, suggesting these neurons contribute to such behavior by holding temporal information across trials. The silencing of MEC activity impairs the reproduction of memorized intervals and results in an overestimation of elapsed time. Additionally, decoding behavioral performance from preceding waiting times is compromised when MEC is silenced, indicating a key role of MEC in maintaining temporal memories across trials.
JOURNAL OF NEUROSCIENCE
(2021)
Article
Psychology, Experimental
Goncalo A. Oliveira, Miguel Remondes, Teresa Garcia-Marques
Summary: Conflict and perceptual disfluency can lead to adaptive control adjustments and these effects may be integrated into a general feeling of disfluent information processing. Results showed that increasing processing disfluency led to a decrease in the interference of incongruent fluent trials, and this effect was significant for all conditions of proportion of congruence, although it was lower when incongruent trials were more frequent. These findings highlight the role of feelings in initiating control and suggest that changes in information processing fluency may serve as a signal for the need for control.
PSYCHOLOGICAL RESEARCH-PSYCHOLOGISCHE FORSCHUNG
(2022)
Article
Psychology, Biological
Goncalo A. Oliveira, Miguel Remondes, Teresa Garcia-Marques
Summary: Recent research suggests that the cognitive monitoring system may use negative emotional cues to regulate information processing. However, this study proposes that positive feelings of ease-of-processing can hinder adaptive control adjustments. The study found that in mostly congruent contexts, participants made more errors on incongruent trials that were easy-to-read. Similarly, in mostly incongruent contexts, participants made more errors after experiencing the facilitation effect of repeated congruent trials. These findings highlight the importance of transient and sustained feelings of processing fluency in regulating control mechanisms.
QUARTERLY JOURNAL OF EXPERIMENTAL PSYCHOLOGY
(2023)
