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Sparse activity of identified dentate granule cells during spatial exploration.

ABSTRACT: In the dentate gyrus - a key component of spatial memory circuits - granule cells (GCs) are known to be morphologically diverse and to display heterogeneous activity profiles during behavior. To resolve structure-function relationships, we juxtacellularly recorded and labeled single GCs in freely moving rats. We found that the vast majority of neurons were silent during exploration. Most active GCs displayed a characteristic spike waveform, fired at low rates and showed spatial activity. Primary dendritic parameters were sufficient for classifying neurons as active or silent with high accuracy. Our data thus support a sparse coding scheme in the dentate gyrus and provide a possible link between structural and functional heterogeneity among the GC population.

SUBMITTER: Diamantaki M

PROVIDER: S-EPMC5077296 | biostudies-literature | 2016 Oct

REPOSITORIES: biostudies-literature

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Sparse activity of identified dentate granule cells during spatial exploration.

Diamantaki Maria M Frey Markus M Berens Philipp P Preston-Ferrer Patricia P Burgalossi Andrea A

eLife 20161003

In the dentate gyrus - a key component of spatial memory circuits - granule cells (GCs) are known to be morphologically diverse and to display heterogeneous activity profiles during behavior. To resolve structure-function relationships, we juxtacellularly recorded and labeled single GCs in freely moving rats. We found that the vast majority of neurons were silent during exploration. Most active GCs displayed a characteristic spike waveform, fired at low rates and showed spatial activity. Primary ...[more]

PMID: 27692065

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