Hippocampal sequence-encoding driven by a cortical multi-item working memory buffer

  title={Hippocampal sequence-encoding driven by a cortical multi-item working memory buffer},
  author={Ole Jensen and John E. Lisman},
  journal={Trends in Neurosciences},

Figures from this paper

Hippocampal Sequences During Exploration: Mechanisms and Functions

Several lines of evidence are presented suggesting that these neural sequences play a key role in information processing and support the formation of initial memory traces, and potential functional distinctions between neural sequences emerging during theta vs. awake sharp-wave ripples are discussed.

Hippocampus dependent and independent theta-networks ofworking memory maintenance

The results demonstrate that working memory maintenance of configural-relational information is supported by a theta synchronous network coupling frontal, temporal and occipital visual areas, and that this theta synchrony is critically dependent on the integrity of the hippocampus.

Phase-dependent neuronal coding of objects in short-term memory

This work shows that neuronal information about two objects held in short-term memory is enhanced at specific phases of underlying oscillatory population activity, and suggests that oscillatory neuronal synchronization mediates a phase-dependent coding of memorized objects in the prefrontal cortex.

The hippocampus: a special place for time

The findings converge toward the idea that the hippocampus is essential for learning sequences of events, allowing the brain to distinguish between memories for conceptually similar but temporally distinct episodes, and to associate representations of temporally contiguous, but otherwise unrelated experiences.

Fast-backward replay of sequentially memorized items in humans

It is demonstrated that serially remembered items are successively reactivated during memory retention and the sequential replay displays two interesting properties compared to the actual sequence, suggesting that external events are associated within a plasticity-relevant window to facilitate memory consolidation.

Matching storage and recall: hippocampal spike timing–dependent plasticity and phase response curves

A normative theory of autoassociative memory encompassing network dynamics of hippocampus area CA3 is developed and it is demonstrated directly that the attributes of phase response curves of CA3 pyramidal cells recorded in vitro qualitatively conform with the theory.

An event map of memory space in the hippocampus

Monitoring the de novo formation of a spatio-temporal representation of space and time in humans using fMRI provides evidence for a common coding mechanism underlying spatial and temporal aspects of episodic memory in the hippocampus and sheds new light on its role in interleaving multiple episodes in a neural event map of memory space.

A model of working memory for encoding multiple items and ordered sequences exploiting the theta-gamma code

This work presents an original neural network model, based on oscillating neural masses, to investigate mechanisms at the basis of working memory in different conditions, and shows that this model, with different synapse values, can be used to address different problems, such as the reconstruction of an item from partial information, the maintenance of multiple items simultaneously in memory, without any sequential order.

Electrophysiological signature of working and long‐term memory interaction in the human hippocampus

Time‐frequency analysis revealed that a reduction of slow hippocampal activity in the delta frequency range supported LTM formation in the low load condition, but not during high WM load, which indicates that multi‐item WM and LTM encoding interfere within the hippocampus.



Hippocampal CA3 region predicts memory sequences: accounting for the phase precession of place cells.

The general success of the model provides support for the idea that the hippocampus stores sequence information and makes predictions of expected positions during gamma-frequency recall.

A theory of hippocampal memory based on theta phase precession

It is concluded that theta phase precession provides biologically plausible dynamics for the memory encoding of novel temporal sequences as episodic events.

Functional significance of long-term potentiation for sequence learning and prediction.

It is found that, due to a temporal asymmetry in the induction of NMDA-mediated LTP, firing patterns in a neuronal array that initially represent the current value of a sensory input will, after training, provide an experienced-based prediction of that input instead.

Physiologically realistic formation of autoassociative memory in networks with theta/gamma oscillations: role of fast NMDA channels.

The results indicate that a limited memory-capacity STM model can be integrated in the same network with a high-capacity LTM model, and the first proposal for the special role of these fast NMDA channels.

Human memory formation is accompanied by rhinal–hippocampal coupling and decoupling

Recorded depth-EEG from within the MTL of epilepsy patients performing a memorization task suggested that effective declarative memory formation is accompanied by a direct and temporarily limited cooperation between both MTL substructures.

Differential Information Processing by Hippocampal and Subicular Neurons

Abstract: It has been known for some years that hippocampal neurons are critically involved in processing of information necessary for encoding memories. What is less understood is the role of the

Prospective and Retrospective Memory Coding in the Hippocampus