The Range of Intrinsic Frequencies Represented by Medial Entorhinal Cortex Stellate Cells Extends with Age
- Anne Boehlen1,3,
- Uwe Heinemann1,2,3, and
- Irina Erchova4
- 1Institute of Neurophysiology, Charité, and
- 2NeuroCure Research Center, 10117 Berlin, Germany,
- 3Bernstein Center for Computational Neuroscience Berlin, 10115 Berlin, Germany, and
- 4Institute for Adaptive and Neural Computation, School of Informatics and Centre of Neuroscience Research, University of Edinburgh, Edinburgh EH8 9AB, United Kingdom
- Correspondence should be addressed to Dr. Irina Erchova, Institute for Adaptive and Neural Computation, School of Informatics, University of Edinburgh, Informatics Forum, 10 Crichton Street, Edinburgh EH8 9AB, UK. ierchova{at}staffmail.ed.ac.uk
Abstract
In both humans and rodents, the external environment is encoded in the form of cognitive maps. Neurons in the medial entorhinal cortex (mEC) represent spatial locations in a sequence of grid-like patterns scaled along the dorsal–ventral axis. The grid spacing correlates with the intrinsic resonance frequencies of stellate cells in layer II of mEC. We investigated the development of frequency preferences in these cells from weaning to adulthood using patch-clamp and sharp microelectrode recordings. We found that the dorsal–ventral gradient of stellate cell properties and frequency preferences exists before animals are able to actively explore their environment. In the transition to adulthood, cells respond faster and become less excitable, and the range of intrinsic resonance frequencies in the population expands in the dorsal direction. This is likely to reflect both the growth of the brain and the expansion of the internal representation caused by new exploratory experience.
- Copyright © 2010 the authors 0270-6474/10/304585-05$15.00/0
