Long-term stability of cortical ensembles

eLife, Journal Year: 2021, Volume and Issue: 10

Published: July 30, 2021

Neuronal ensembles, coactive groups of neurons found in spontaneous and evoked cortical activity, are causally related to memories perception, but it is still unknown how stable or flexible they over time. We used two-photon multiplane calcium imaging track weeks the activity same pyramidal layer 2/3 visual cortex from awake mice recorded their visually responses. Less than half remained active across any two sessions. These formed ensembles that lasted weeks, some were also transient appeared only one single session. Stable preserved most for up 46 days, our longest imaged period, these 'core' cells had stronger functional connectivity. Our results demonstrate neuronal can last could, principle, serve as a substrate long-lasting representation perceptual states memories.

Language: Английский

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Intrinsic excitability mechanisms of neuronal ensemble formation

eLife, Journal Year: 2022, Volume and Issue: 11

Published: May 4, 2022

Neuronal ensembles are coactive groups of cortical neurons, found in spontaneous and evoked activity, that can mediate perception behavior. To understand the mechanisms lead to formation ensembles, we co-activated layer 2/3 pyramidal neurons brain slices from mouse visual cortex, animals both sexes, replicating vitro an optogenetic protocol generate vivo. Using whole-cell perforated patch-clamp pair recordings that, after or electrical stimulation, coactivated increased their correlated a hallmark ensemble formation. Coactivated showed small biphasic changes presynaptic plasticity, with initial depression followed by potentiation recovery period. Optogenetic stimulation also induced significant increases frequency amplitude EPSPs, even single-cell stimulation. In addition, observed unexpected strong persistent neuronal excitability membrane resistance reductions spike threshold. A pharmacological agent blocks reverted this effect. These explain synaptic plasticity. We conclude cell-intrinsic involved ensembles. propose ‘iceberg’ model, which makes subthreshold connections suprathreshold, enhancing effect already existing synapses, generating new ensemble.

Language: Английский

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Latent neural population dynamics underlying breathing, opioid-induced respiratory depression and gasping

Nature Neuroscience, Journal Year: 2024, Volume and Issue: unknown

Published: Jan. 5, 2024

Abstract Breathing is vital and must be concurrently robust flexible. This rhythmic behavior generated maintained within a rostrocaudally aligned set of medullary nuclei called the ventral respiratory column (VRC). The properties individual VRC are well known, yet technical challenges have limited interrogation entire population simultaneously. Here we characterize over 15,000 units using high-density electrophysiology, opto-tagging histological reconstruction. Population dynamics analysis reveals consistent rotational trajectories through low-dimensional neural manifold. These rotations even during opioid-induced depression. During severe hypoxia-induced gasping, reconfigure from to all-or-none, ballistic efforts. Thus, latent provide unifying lens onto activities large, heterogeneous populations neurons involved in simple, vital, breathing, describe how these respond variety perturbations.

Language: Английский

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Stimulus encoding by specific inactivation of cortical neurons

Nature Communications, Journal Year: 2024, Volume and Issue: 15(1)

Published: April 12, 2024

Abstract Neuronal ensembles are groups of neurons with correlated activity associated sensory, motor, and behavioral functions. To explore how encode information, we investigated responses visual cortical in awake mice using volumetric two-photon calcium imaging during stimulation. We identified neuronal employing an unsupervised model-free algorithm and, besides activated by the stimulus (termed “onsemble”), also find that specifically inactivated “offsemble”). Offsemble showed faster decay stimuli, suggesting selective inhibition. In response to each ensemble (onsemble+offsemble) exhibited small trial-to-trial variability, high orientation selectivity, superior predictive accuracy for orientation, surpassing sum individual neuron activity. Thus, combined activation inactivation enhances encoding as emergent distributed neural code.

Language: Английский

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Chronic sustained hypoxia alters the pattern of diaphragm electrical activity in anaesthetized rats

Experimental Physiology, Journal Year: 2025, Volume and Issue: unknown

Published: Feb. 24, 2025

Chronic sustained hypoxia (CSH) is known to induce functional and structural changes in the respiratory system. The diaphragm, as main inspiratory muscle of mammals, particularly important neuromotor regulation respiration. Diaphragm electromyography (dEMG) records sum motor unit action potentials (MUAP) provides information regarding recruitment frequency coding during contraction. We aimed assess dEMG activity following CSH. Herein, eight male Wistar rats (2-3 months) were subjected CSH (10 ± 0.5% O2) for 10 successive days. In vivo recording was employed diaphragm electrical activity. Filtered rectified dEMGs used further analyses. Findings showed that consecutive days significantly changed pattern signals. slope rising phase RMS-enveloped bursts much steeper compared normoxic control (rise time: 373 vs. 286 ms; P = 0.005). Burst decreased (59 42 bursts/min; 0.0001), which associated with a significant increase burst amplitude (P 0.039) inter-burst duration (0.65 0.88 s; 0.041). Power spectral density analyses mean (293 266 Hz; 0.033) high-frequency low-frequency power ratio 0.009) signals declined rats. Notably, regularity did not change

Language: Английский

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Abnormal innate and learned behavior induced by neuron–microglia miscommunication is related to CA3 reconfiguration

Glia, Journal Year: 2022, Volume and Issue: 70(9), P. 1630 - 1651

Published: May 10, 2022

Abstract Neuron–microglia communication through the Cx3cr1–Cx3cl1 axis is essential for development and refinement of neural circuits, which determine their function into adulthood. In present work we set out to extend behavioral characterization Cx3cr1 −/− mice evaluating innate behaviors spatial navigation, both dependent on hippocampal function. Our results show that Cx3cr1‐deficient mice, some changes in microglial synaptic terminals morphology density, exhibit alterations activities daily living rapid encoding novel information that, nonetheless, improves with training. A substrate these cognitive deficiencies was found form dysfunction CA3 region hippocampus, a marked impact mossy fiber (MF) pathway. network analysis microcircuit reveals effect functional connectivity among neurons diminished strength topological reorganization mice. Neonatal population activity shows around giant depolarizing potentials, first network‐driven suggesting adult subjects arise early postnatal development, critical period microglia‐dependent circuit refinement. interruption Cx3cr1–Cx3cl1/neuron–microglia leads configuration affect learned behaviors.

Language: Английский

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Predictions and experimental tests of a new biophysical model of the mammalian respiratory oscillator

eLife, Journal Year: 2022, Volume and Issue: 11

Published: July 5, 2022

Previously our computational modeling studies (Phillips et al., 2019) proposed that neuronal persistent sodium current (INaP) and calcium-activated non-selective cation (ICAN) are key biophysical factors that, respectively, generate inspiratory rhythm burst pattern in the mammalian preBötzinger complex (preBötC) respiratory oscillator isolated vitro. Here, we experimentally tested confirmed three predictions of model from new simulations concerning roles INaP ICAN: (1) ICAN blockade have opposite effects on relationship between network excitability preBötC rhythmic activity; (2) is essential for rhythmogenesis; (3) generating amplitude output but not generation. These were via optogenetic manipulations during graded or by pharmacological slices vitro containing rhythmically active medulla oblongata neonatal mice. Our results support advance hypothesis mechanistically underlie generation, preBötC.

Language: Английский

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Perinatal inflammation and gestational intermittent hypoxia disturbs respiratory rhythm generation and long-term facilitation in vitro: Partial protection by acute minocycline

Respiratory Physiology & Neurobiology, Journal Year: 2021, Volume and Issue: 297, P. 103829 - 103829

Published: Dec. 15, 2021

Language: Английский

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Intrinsic excitability mechanisms of neuronal ensemble formation

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2020, Volume and Issue: unknown

Published: July 29, 2020

Abstract Neuronal ensembles are coactive groups of cortical neurons, found in spontaneous and evoked activity, that can mediate perception behavior. To understand the mechanisms lead to formation ensembles, we co-activated optogenetically electrically layer 2/3 pyramidal neurons brain slices from mouse visual cortex, animals both sexes, replicating vitro an optogenetic protocol generate vivo . Using whole-cell perforated patch-clamp pair recordings find that, after or electrical stimulation, coactivated increase their correlation a hallmark ensemble formation. Coactivated showed small biphasic changes presynaptic plasticity, with initial depression followed by potentiation recovery period. Unexpectedly, stimulation-induced significant increases frequency amplitude EPSPs, even single-cell stimulation. In addition, observed strong persistent neuronal excitability membrane resistance reduction spike threshold. A pharmacological agent blocks revert this effect. These may partly explain synaptic plasticity. We propose cell-intrinsic involved ensembles. “iceberg” model, which increased makes subthreshold connections suprathreshold, enhancing effect already existing synapses, generating new ensemble. Significance Statement investigated cellular underlying i.e., spontaneously neurons. electrophysiology neocortex replicated generates After plasticity and, unexpectedly, major excitability, input resistance, reductions firing The Our results reveal role for intrinsic establishment

Language: Английский

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The hypoxic respiratory response of the pre-Bötzinger complex

Heliyon, Journal Year: 2024, Volume and Issue: 10(14), P. e34491 - e34491

Published: July 1, 2024

Language: Английский

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