Sparse Activity of Identified Dentate Granule Cells During Spatial Exploration

Elife. 2016 Oct 3;5:e20252. doi: 10.7554/eLife.20252.

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.

Keywords: dentate gyrus; granule cell; juxtacellular; neuroscience; place cell; rat; spatial navigation.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Action Potentials
  • Animals
  • Dentate Gyrus / physiology*
  • Neurons / physiology*
  • Rats
  • Spatial Learning*
  • Spatial Memory*

Grant support

The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.