Linking temporal coordination of hippocampal activity to memory function

Frontiers in Cellular Neuroscience, Journal Year: 2023, Volume and Issue: 17

Published: Aug. 31, 2023

Oscillations in neural activity are widespread throughout the brain and can be observed at population level through local field potential. These rhythmic patterns associated with cycles of excitability thought to coordinate networks neurons, turn facilitating effective communication both within circuits across regions. In hippocampus, theta rhythms (4–12 Hz) could contribute several key physiological mechanisms including long-range synchrony, plasticity, behavioral scale, support memory encoding retrieval. While neurons hippocampus appear temporally coordinated by oscillations, they also tend fire sequences that developmentally preconfigured. Although loss rhythmicity impairs memory, these spatiotemporal representations persist conditions altered hippocampal oscillations. The focus this review is disentangle relative contribution oscillations from single-neuron learning memory. We first cellular, anatomical, underlying generation maintenance how function. propose candidate hypotheses for septohippocampal function while not contributing directly sequences. particular, we explore integration upstream signals form future decisions, relevance such downstream regions, as well setting stage timescale synaptic plasticity. Finally, leverage stimulation-based treatment Alzheimer's disease an opportunity assess sufficiency

Language: Английский

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Theta cycle dynamics of spatial representations in the lateral septum

Published: May 9, 2024

An internal representation of the environment – or map allows animals to evaluate multiple routes and adapt their navigation strategy current needs future goals. The hippocampal formation plays a crucial role in learning spatial using for goal-directed navigation. lateral septum forms major node connections between hippocampus subcortical brain regions that could link motivation reward processing centers such as ventral tegmental area hypothalamus. It is not known, however, how contributes information route planning.In this study, we investigated temporal dynamics representations septum. Neuropixels probes were used record cellular activity along dorsal-ventral extent while rats performed one two tasks Y-maze. large fraction cells was theta rhythmic subset showed evidence being active on alternate cycles (theta cycle skipping). Both rhythmicity skipping strongest dorsal Similarly, spatially selective firing most prominent Using neural decoding, show cell population encodes both location alternatingly possible paths within single when approach choice point maze.Our data further shows alternating expression task-dependent, it task also requires rewarded goal arms. These suggest demands experience shape which are activated near point. receives strong input from place cells, there may be integration transformation incoming signals, our findings support idea conveyed projection areas through

Language: Английский

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Fundamentals of the septo-hippocampal system

Oxford University Press eBooks, Journal Year: 2024, Volume and Issue: unknown, P. 241 - 284

Published: May 7, 2024

Abstract ‘Fundamentals of the septo-hippocampal system’ derives a range data principles from an overview sept-hippocampal data. It reviews anxiolytic action on system and behaviour; control rhythmical slow activity (RSA)/‘theta’ activity; relationship to sensory processing, working/active memory, conditioning, emotion. then discusses how approach understanding system, its anatomy, role in long-term memory via mismatch detection. emphasizes important affectively linked neuromodulatory systems hippocampal function; hippocampus at least 70 chemical factors, including corticosterone/cortisol. Its series are solidly based available so all theories should be judged against them. While place severe limits assumptions machinery theory, they not sufficient provide theory themselves.

Language: Английский

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Imagination, creativity, fun and innovation

Revista Científica de la Sociedad de Enfermería Neurológica (English ed ), Journal Year: 2022, Volume and Issue: 56, P. 2 - 3

Published: July 1, 2022

Language: Английский

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Electrophysiological properties of the medial mammillary bodies across the sleep-wake cycle

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2023, Volume and Issue: unknown

Published: Nov. 2, 2023

Abstract The medial mammillary bodies (MB) play an important role in the formation of spatial memories. Dense anatomical connectivity with hippocampal, brainstem, and thalamic structures, positions them as a focal point for integration movement-related information that is extended to anterior nuclei beyond cortex. While their has been well-studied, much less known about physiological properties MBs, particularly freely moving animals. We therefore carried out comprehensive characterization MB electrophysiology across arousal states by concurrently recording from CA1 field hippocampus. In agreement previous studies, we found neurons have firing rates modulated running speed angular head velocity, well theta-entrained firing. neuron three key ways: 1) identified subset (25%) exhibit dominant bursting activity; 2) show ∼30% robust theta cycle skipping, characteristic implicates network prospective coding position; 3) A considerable proportion units sharp wave-ripple (SWR) responsive (∼37%). functional heterogeneity reinforces integrative node mnemonic processing identifies potential roles MBs memory consolidation through propagation SWR-responsive activity thalamus form theta-cycle skipping. Significance Statement (MBs) are memory, it still not clear how they support formation. Through conjoint hippocampal recordings different population diverse often conjunctive properties, including cells, cells complex bursting, skipping activity, sharp-wave ripple-responsive These likely processing, enabling separate sensory streams thalamus.

Language: Английский

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Large‐scale brain correlates of sweet versus cocaine reward in rats

European Journal of Neuroscience, Journal Year: 2022, Volume and Issue: 57(3), P. 423 - 439

Published: Dec. 1, 2022

Abstract Cocaine induces many supranormal changes in neuronal activity the brain, notably learning‐ and reward‐related regions, comparison with nondrug rewards—a difference that is thought to contribute its relatively high addictive potential. However, when facing a choice between cocaine reward (e.g., water sweetened saccharin), most rats do not choose cocaine, as one would expect from extent magnitude of global activation but instead option. We recently showed though larger magnitude, also an inherently more delayed than sweet water, thereby explaining why it has less value during opt for immediate Here, we used large‐scale Fos brain mapping approach measure responses each option saccharin‐preferring rats, hope identify regions whose may explain preference In total, expression was measured 142 levels corresponding 52 subregions composing 5 macrosystems. Overall, our findings confirm saccharin preferred does. Only very few were uniquely activated by saccharin. They included involved taste processing (i.e., anterior gustatory cortex) delay intertemporal some components septohippocampal system connections lateral habenula).

Language: Английский

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Theta cycle dynamics of spatial representations in the lateral septum

Published: Oct. 9, 2023

An internal representation of the environment – or map allows animals to evaluate multiple routes and adapt their navigation strategy current needs future goals. The hippocampal formation plays a crucial role in learning spatial using for goal-directed navigation. lateral septum forms major node connections between hippocampus subcortical brain regions that could link motivation reward processing centers such as ventral tegmental area. It is not known, however, how contributes information route planning.In this study we investigated temporal dynamics representations septum. Neuropixels probes were used record cellular activity along dorsal-ventral extent while rats performed one two tasks Y-maze. large fraction cells was theta rhythmic subset showed evidence being active on alternate cycles (theta cycle skipping). Both rhythmicity skipping strongest dorsal Similarly, spatially selective firing most prominent later Using neural decoding, show cell population encodes both location alternatingly possible paths within single when approached choice point maze.Our data further shows alternating expression task dependent, it also requires rewarded goal arms. These suggests demands experience shape which are activated near point. receives strong input from place cells, there may be integration transformation incoming signals, our findings support idea conveyed projection areas through

Language: Английский

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Theta cycle dynamics of spatial representations in the lateral septum

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2023, Volume and Issue: unknown

Published: July 19, 2023

Summary An internal representation of the environment – or map allows animals to evaluate multiple routes and adapt their navigation strategy current needs future goals. The hippocampal formation plays a crucial role in learning spatial using for goal-directed navigation. lateral septum forms major node connections between hippocampus subcortical brain regions that could link motivation reward processing centers such as ventral tegmental area hypothalamus. It is not known, however, how contributes information route planning. In this study, we investigated temporal dynamics representations septum. Neuropixels probes were used record cellular activity along dorsal-ventral extent while rats performed one two tasks Y-maze. large fraction cells was theta rhythmic subset showed evidence being active on alternate cycles (theta cycle skipping). Both rhythmicity skipping strongest dorsal Similarly, spatially selective firing most prominent Using neural decoding, show cell population encodes both location alternatingly possible paths within single when approach choice point maze. Our data further shows alternating expression task-dependent, it task also requires rewarded goal arms. These suggest demands experience shape which are activated near point. receives strong input from place cells, there may be integration transformation incoming signals, our findings support idea conveyed projection areas through

Language: Английский

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Nicotine use disorder and Neuregulin 3: Opportunities for precision medicine

Advances in pharmacology, Journal Year: 2024, Volume and Issue: unknown, P. 387 - 404

Published: Jan. 1, 2024

Language: Английский

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Distinct and Convergent Alterations of Entorhinal Cortical Circuits in Two Mouse Models for Alzheimer’s Disease and Related Disorders

Journal of Alzheimer s Disease, Journal Year: 2024, Volume and Issue: 98(3), P. 1121 - 1131

Published: March 14, 2024

The impairment of neural circuits controlling cognitive processes has been implicated in the pathophysiology Alzheimer's disease and related disorders (ADRD). However, it is largely unclear what are specifically changed ADRD, particularly at early stage.

Language: Английский

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