Synaptic plasticity rules driving representational shifting in the hippocampus

Nature Neuroscience, Journal Year: 2025, Volume and Issue: unknown

Published: March 20, 2025

Language: Английский

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Goal-specific hippocampal inhibition gates learning

Nature, Journal Year: 2025, Volume and Issue: unknown

Published: April 9, 2025

Goal-directed navigation in a new environment requires quickly identifying and exploiting important locations. Identifying goal locations depends on neural computations that rapidly represent connect location information to key outcomes such as food1. However, the mechanisms trigger these at behaviourally relevant are not well understood. Here we show parvalbumin (PV)-positive interneurons mouse hippocampal CA3 have causal role food decreases inhibitory activity around goals enable reactivation bind outcomes. PV substantially reduce firing approach while food-deprived mice learn find food. These anticipate reward more prominent correct trials. Sparse optogenetic stimulation prevent goal-related interneuron impaired learning of Disrupting after receipt food, process associates previous know where seek later. results reveal goal-selective goal-predictive learning, representations outcome associations crucial

Language: Английский

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A non-Hebbian code for episodic memory

Science Advances, Journal Year: 2025, Volume and Issue: 11(8)

Published: Feb. 21, 2025

Hebbian plasticity has long dominated neurobiological models of memory formation. Yet, rules operating on one-shot episodic timescales rarely depend both pre- and postsynaptic spiking, challenging theory in this crucial regime. Here, we present an model governed by a simpler rule depending only presynaptic activity. We show that rule, capitalizing high-dimensional neural activity with restricted transitions, naturally stores episodes as paths through complex state spaces like those underlying world model. The resulting traces, which term path vectors, are highly expressive decodable odor-tracking algorithm. vectors robust alternatives to support sequential associative recall, along policy learning, shed light specific hippocampal rules. Thus, non-Hebbian is sufficient for flexible learning well-suited encode policies

Language: Английский

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Recurrent Connectivity Shapes Spatial Coding in Hippocampal CA3 Subregions

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2024, Volume and Issue: unknown

Published: Nov. 7, 2024

Abstract Stable and flexible neural representations of space in the hippocampus are crucial for navigating complex environments. However, how these distinct emerge from underlying local circuit architecture remains unknown. Using two-photon imaging CA3 subareas during active behavior, we reveal opposing coding strategies within specific subregions, with proximal neurons demonstrating stable generalized distal showing dynamic context-specific activity. We show artificial network models that varying recurrence level causes differences properties to emerge. confirmed contribution recurrent connectivity functional heterogeneity by characterizing representational geometry recordings comparing it theoretical predictions manifold dimensionality. Our results indicate organization, particularly among excitatory neurons, plays a key role shaping complementary spatial hippocampus.

Language: Английский

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One-shot learning and robust recall with BTSP, a biological synaptic plasticity rule

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

Published: April 4, 2023

ABSTRACT Recent experimental studies in the awake brain have identified a rule for synaptic plasticity that is instrumental instantaneous creation of memory traces area CA1 mammalian brain: Behavioral Time scale Synaptic Plasticity. This one-shot learning differs five essential aspects from previously considered mechanisms. We introduce transparent model core function this and establish theory enables principled understanding system it creates. Theoretical predictions numerical simulations show our able to create functionally powerful content-addressable without need high-resolution weights. Furthermore, reproduces repulsion effect human memory, whereby similar items are pulled apart enable differential downstream processing. Altogether, results link between hippocampus its network function. They also provide promising approach implementing with on-chip capability highly energy-efficient crossbar arrays memristors.

Language: Английский

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From experimental phenomena to computational models: Exploring the synchronization mechanisms of phase-locked stimulation in the hippocampal–thalamic–cortical circuit for memory consolidation

Chaos Solitons & Fractals, Journal Year: 2024, Volume and Issue: 191, P. 115754 - 115754

Published: Nov. 30, 2024

Language: Английский

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