How Informative Are Spatial CA3 Representations Established by the Dentate Gyrus?
- BiologyPLoS Comput. Biol.
This work estimates the amount of information DG can impart on a new CA3 pattern of spatial activity, and indicates that even when DG codes just for space, much of the information it passes on to CA3 acquires a non-spatial and episodic character, akin to that of a random number generator.
THE DENTATE GYRUS, DEFINING A NEW MEMORY OF DAVID MARR 1
The dentate gyrus is one subdivision of the mammalian hippocampus which has no clear correspondence in birds or reptiles, despite any superficial homology, and is thus at the same time the most striking component, within the structure in the authors' brain which is critical for memory formation, and the component most difficult to understand.
Pattern separation in the dentate gyrus: A role for the CA3 backprojection
A simple CA3 network model is considered, and it is hypothesize that CA3 backprojections might play an important role in hippocampal function, and shows that the DG‐CA3 model with backprojection provides a better fit to empirical data than a model without back projections.
Pattern separation in the hippocampus: distinct circuits under different conditions
- BiologyBrain Structure and Function
It is argued for the case that sparse coding is necessary but not sufficient to ensure efficient separation and, alternatively, a possible interaction of distinct circuits which, nevertheless, act in synergy to produce a unitary function of pattern separation are proposed.
Spatial Cognition, Memory Capacity, and the Evolution of Mammalian Hippocampal Networks
- Biology, Psychology
It now appears, more clearly than before, that spatial computations per se are largely performed by the rat brain before the hippocampus is ever accessed, and culminate in a sort of universal map of allocentric space, in MEC layer II.
Disambiguating the similar: The dentate gyrus and pattern separation
- Biology, PsychologyBehavioural Brain Research
Distinct dendritic morphology across the blades of the rodent dentate gyrus
It is found that granule cells from the suprapyramidal blade of the DG contain greater dendritic material in the region receiving spatial information from the medial perforant path, providing a potential anatomical substrate for the asymmetric response of the dentate gyrus to spatial input.
Monosynaptic inputs to new neurons in the dentate gyrus.
- BiologyNature communications
The results show that newborn granule cells receive afferents from intra-hippocampal cells (interneurons, mossy cells, area CA3 and transiently, maturegranule cells) and septal cholinergic cells and PRH/LEC input is an important functional component of new dentate gyrus neuron circuitry.
Mature granule cells of the dentate gyrus—Passive bystanders or principal performers in hippocampal function?
- BiologyNeuroscience & Biobehavioral Reviews
Separation or binding? Role of the dentate gyrus in hippocampal mnemonic processing
- Biology, PsychologyNeuroscience & Biobehavioral Reviews
SHOWING 1-10 OF 254 REFERENCES
Encoding and retrieval in the CA3 region of the hippocampus: a model of theta-phase separation.
- BiologyJournal of neurophysiology
A model of the CA3 subfield of the hippocampus is presented, using biophysical representations of the major cell types including pyramidal cells and two types of interneurons, and slow inhibitory neurons (O-LM cells) play a role in the disambiguation during retrieval.
Computational constraints suggest the need for two distinct input systems to the hippocampal CA3 network
The CA3 network in the hippocampus may operate as an autoassociator, in which declarative memories, known to be dependent on hippocampal processing, could be stored, and subsequently retrieved, using…
Distinct short-term plasticity at two excitatory synapses in the hippocampus.
- BiologyProceedings of the National Academy of Sciences of the United States of America
The results indicate that the mossy fiber synapse is able to integrate granule cell spiking activity over a broad range of frequencies, and this dynamic range is substantially reduced by long-term potentiation.
Models, structure, function: the transformation of cortical signals in the dentate gyrus.
- BiologyProgress in brain research
Pattern Separation in the Dentate Gyrus and CA3 of the Hippocampus
- Biology, PsychologyScience
These results imply a dual mechanism for pattern separation in which signals from the entorhinal cortex can be decorrelated both by changes in coincidence patterns in the dentate gyrus and by recruitment of nonoverlapping cell assemblies in CA3.
A computational principle for hippocampal learning and neurogenesis
- Biology, Computer ScienceHippocampus
Simulations of the complete circuit confirm that both recognition memory and recall are superior relative to a hippocampally lesioned model, consistent with human data and support the prediction that memory capacity increases with the number of dentate granule cells, while neuronal turnover with a fixed dentate layer size improves recall.
Dentate Gyrus NMDA Receptors Mediate Rapid Pattern Separation in the Hippocampal Network
- Biology, PsychologyScience
Evidence is provided that NMDA receptors in the granule cells of the dentate gyrus play a crucial role in the process of pattern separation, by generating and analyzing a mouse strain that lacks the gene encoding the essential subunit of the N-methyl-d-aspartate (NMDA) receptor NR1 in dentates gyrus granule Cells.
Cholinergic suppression of glutamatergic synaptic transmission in hippocampal region CA3 exhibits laminar selectivity: Implication for hippocampal network dynamics
Entorhinal cortex grid cells can map to hippocampal place cells by competitive learning
It is shown that the learning in the competitive network is an important part of the way in which the mapping of EC grid cells to dentate place cells is achieved and incorporation of a short term memory trace into the associative learning can help to produce the relatively broad place fields found in the hippocampus.
The fine structure of the mossy fibre endings in the hippocampus of the rabbit.
The site of termination of these fibres has been investigated with the electron microscope and where possible the results have been correlated with those of light microscopy.