Neuronal Ensembles Organize Activity to Generate Contextual Memory

Frontiers in Behavioral Neuroscience, Journal Year: 2022, Volume and Issue: 16

Published: March 15, 2022

Contextual learning is a critical component of episodic memory and important for living in any environment. Context can be described as the attributes location that are not itself. This includes variety non-spatial information derived from sensory systems (sounds, smells, lighting, etc.) internal state. In this review, we first address behavioral underpinnings contextual development context theory, with particular focus on fear conditioning paradigm means assessing underlying processes contributing to it. We then present various neural centers play roles learning. continue discussion current knowledge circuitry physiological underlie representations Entorhinal cortex-Hippocampal (EC-HPC) circuit, most well studied contributor memory, focusing role ensemble activity representation description remapping, pattern separation completion processing information. discuss other regions involved formation retrieval. finally consider engram assembly an indicator stored memories its potential contribution memory.

Language: Английский

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Systems consolidation induces multiple memory engrams for a flexible recall strategy in observational fear memory in male mice

Nature Communications, Journal Year: 2023, Volume and Issue: 14(1)

Published: July 5, 2023

Abstract Observers learn to fear the context in which they witnessed a demonstrator’s aversive experience, called observational contextual conditioning (CFC). The neural mechanisms governing whether recall of CFC memory occurs from observer’s own or point view remain unclear. Here, we show male mice that recent is recalled only, but remote both observer and demonstrator contexts. Recall requires dorsal hippocampus activity, while contexts medial prefrontal cortex (mPFC)-basolateral amygdala pathway. Although mPFC neurons activated by are involved contexts, distinct subpopulations regulate each context. Our data provide insights into flexible strategy functional reorganization circuits engram cells underlying memory.

Language: Английский

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Pain-related neuronal ensembles in the primary somatosensory cortex contribute to hyperalgesia and anxiety

iScience, Journal Year: 2023, Volume and Issue: 26(4), P. 106332 - 106332

Published: March 4, 2023

The mechanism by which acute pain or itch information at the periphery is processed in primary somatosensory cortex (S1) remains unclear. To elucidate this, we used a viral-mediated targeted-recombination-in-active population system to target S1 neuronal ensembles that are active during sensations. We induced expression of excitatory inhibitory designer receptors exclusively activated drugs pain- itch-related neurons. identified populations mice regulate sensory components and hind paw region. Notably, circuit between pain-related neurons parafascicular nucleus contributed hyperalgesia anxiety-like behavior. propose plays an essential role affective responses noxious stimuli, such as pain.

Language: Английский

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Dorsal raphe serotonergic neurons preferentially reactivate dorsal dentate gyrus cell ensembles associated with positive experience

Cell Reports, Journal Year: 2023, Volume and Issue: 42(3), P. 112149 - 112149

Published: Feb. 22, 2023

Major depressive disorder (MDD) is among the most common mental illnesses. Serotonergic (5-HT) neurons are central to pathophysiology and treatment of MDD. Repeatedly recalling positive episodes effective for Stimulating 5-HT dorsal raphe nucleus (DRN) or neuronal ensembles in dentate gyrus (dDG) associated with memories reverses stress-induced behavioral abnormalities. Despite this phenotypic similarity, their causal relationship unclear. This study revealed that DRN activate dDG neurons; surprisingly, activation was specifically observed memory rather than neutral negative ensembles. Furthermore, we dopaminergic signaling induced by projecting ventral tegmental area mediates an increase active coping behavior ensemble reactivation. Our identifies a role as specific reactivators provides insights into how serotonin elicits antidepressive effects.

Language: Английский

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The Modulation by the Locus Coeruleus of Recent and Remote Memory Retrieval is Activity‐Dependent

Hippocampus, Journal Year: 2025, Volume and Issue: 35(2)

Published: Feb. 20, 2025

ABSTRACT The hippocampus plays a crucial role in acquiring, storing, and retrieving associative experience. Whereas neuromodulatory control of the by locus coeruleus (LC) enhances memory acquisition consolidation, less is known about its influence on retrieval. LC fires at tonic (0.5–8 Hz) phasic frequencies (10–25 Hz), relative to arousal affective states. Here, we explored what extent stimulation different (2–100 respective patterns, before retrieval recently acquired or remote spatial memory, alter working (WM) reference (RM) male rats. animals learned task an eight‐arm radial maze over period 15 days. recent testing did not affect WM. However, 20 100 Hz, but 5–10 impaired consolidated RM. These frequency‐dependent impairments were abolished intracerebral β‐adrenergic receptor (β‐AR), D1/D5 receptor, antagonism. When was assessed 4 weeks after initial consolidation (Day 34), RM significantly compared final day (on Day 6). altered 2–100 Hz improved Taken together, these data suggest that NA release from disrupts via activation β‐AR. Strikingly, increasing activity general improves WM remotely learning task, testing, suggesting increased effort sustaining past requires higher engagement.

Language: Английский

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