Ripple-locked coactivity of stimulus-specific neurons and human associative memory

Nature Neuroscience, Journal Year: 2024, Volume and Issue: 27(3), P. 587 - 599

Published: Feb. 16, 2024

Abstract Associative memory enables the encoding and retrieval of relations between different stimuli. To better understand its neural basis, we investigated whether associative involves temporally correlated spiking medial temporal lobe (MTL) neurons that exhibit stimulus-specific tuning. Using single-neuron recordings from patients with epilepsy performing an object–location task, identified object-specific place-specific represented separate elements each memory. When encoded retrieved particular memories, relevant activated together during hippocampal ripples. This ripple-locked coactivity emerged over time as patients’ learning progressed. Between retrieval, timing shifted, suggesting flexibility in interaction MTL ripples according to behavioral demands. Our results are consistent a cellular account memory, which coordinate activity specialized populations facilitate links

Language: Английский

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Awake ripples enhance emotional memory encoding in the human brain

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

Published: Jan. 3, 2024

Abstract Enhanced memory for emotional experiences is hypothesized to depend on amygdala-hippocampal interactions during consolidation. Here we show using intracranial recordings from the human amygdala and hippocampus an encoding discrimination task increased awake ripples after of emotional, compared neutrally-valenced stimuli. Further, post-encoding ripple-locked stimulus similarity predictive later discrimination. Ripple-locked appears earlier in than mutual information analysis confirms influence hippocampal activity. Finally, joint correct These findings provide electrophysiological evidence that enhance events.

Language: Английский

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Hippocampal sharp-wave ripples correlate with periods of naturally occurring self-generated thoughts in humans

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

Published: May 22, 2024

Abstract Core features of human cognition highlight the importance capacity to focus on information distinct from events in here and now, such as mind wandering. However, brain mechanisms that underpin these self-generated states remain unclear. An emerging hypothesis is depend process memory replay, which linked sharp-wave ripples (SWRs), are transient high-frequency oscillations originating hippocampus. Local field potentials were recorded hippocampus 10 patients with epilepsy for up 15 days, experience sampling was used describe their association ongoing thought patterns. The SWR rates higher during extended periods time when participants’ thoughts more vivid, less desirable, had imaginable properties, exhibited fewer correlations an external task. These data suggest a role patterns humans daily life.

Language: Английский

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Spatiotemporal Patterns Differentiate Hippocampal Sharp-Wave Ripples from Interictal Epileptiform Discharges in Mice and Humans

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2025, Volume and Issue: unknown

Published: Feb. 6, 2025

Abstract Hippocampal sharp-wave ripples (SPW-Rs) are high-frequency oscillations critical for memory consolidation in mammals. Despite extensive characterization rodents, their application as biomarkers to track and treat dysfunction humans is limited by coarse spatial sampling, interference from interictal epileptiform discharges (IEDs), lack of consensus on human SPW-R localization morphology. We demonstrate that mouse hippocampal share spatial, spectral temporal features, which clearly distinct IEDs. In 1024-channel recordings APP/PS1 mice, SPW-Rs were distinguishable IEDs narrow the CA1 pyramidal layer, narrowband frequency peaks, multiple ripple cycles unfiltered local field potential. epilepsy patients, showed similar peaks visible subiculum but absent dentate gyrus. Conversely, a broad extent wide-band power. introduce semi-automated, detection toolbox (“ripmap”) selecting optimal channels separating event waveforms low-dimensional embedding. Our approach improves accuracy, providing firm foundation future research.

Language: Английский

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The Hippocampal Horizon: Constructing and Segmenting Experience for Episodic Memory

Neuroscience & Biobehavioral Reviews, Journal Year: 2021, Volume and Issue: 132, P. 181 - 196

Published: Nov. 24, 2021

Language: Английский

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Looking for the neural basis of memory

Trends in Cognitive Sciences, Journal Year: 2021, Volume and Issue: 26(1), P. 53 - 65

Published: Nov. 23, 2021

Language: Английский

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Offline memory consolidation during waking rest

Nature Reviews Psychology, Journal Year: 2022, Volume and Issue: 1(8), P. 441 - 453

Published: June 13, 2022

Language: Английский

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Recent advances in the neuroscience of spontaneous and off-task thought: implications for mental health

Nature Mental Health, Journal Year: 2023, Volume and Issue: 1(11), P. 827 - 840

Published: Nov. 2, 2023

Language: Английский

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Human hippocampal ripples signal encoding of episodic memories

Journal of Neuroscience, Journal Year: 2024, Volume and Issue: unknown, P. e0111232023 - e0111232023

Published: Jan. 17, 2024

Direct human brain recordings have confirmed the presence of high-frequency oscillatory events, termed ripples, during awake behavior. While many prior studies focused on medial temporal lobe (MTL) ripples memory retrieval, here we investigate encoding. Specifically, ask whether encoding predict and how memories are subsequently recalled. Detecting from MTL electrodes implanted in 116 neurosurgical participants (

Language: Английский

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High frequency oscillations in human memory and cognition: a neurophysiological substrate of engrams?

Brain, Journal Year: 2024, Volume and Issue: 147(9), P. 2966 - 2982

Published: May 14, 2024

Abstract Despite advances in understanding the cellular and molecular processes underlying memory cognition, recent successful modulation of cognitive performance brain disorders, neurophysiological mechanisms remain underexplored. High frequency oscillations beyond classic electroencephalogram spectrum have emerged as a potential neural correlate fundamental processes. are detected human mesial temporal lobe neocortical intracranial recordings spanning gamma/epsilon (60–150 Hz), ripple (80–250 Hz) higher ranges. Separate from other non-oscillatory activities, these brief electrophysiological distinct duration, amplitude thought to be generated by coordinated spiking neuronal ensembles within volumes small single cortical column. Although exact origins, physiological roles health disease elusive, they been associated with consolidation processing. Recent studies suggest their involvement encoding recall episodic possible role formation reactivation traces. during encoding, throughout maintenance, right before remembered items, meeting basic definition for an engram activity. The coordination high reactivated across subcortical networks is ideally suited integrating multimodal representations, which can replayed consolidated states wakefulness sleep. shown reflect bursts assembly firing offer promising substrate tracking hypothetical engram.

Language: Английский

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