FULL-LENGTH ORIGINAL RESEARCH
Altered theta coupling between medial entorhinal cortex and dentate gyrus in temporal lobe epilepsy
Article first published online: 17 SEP 2012
Wiley Periodicals, Inc. © 2012 International League Against Epilepsy
Volume 53, Issue 11, pages 1937–1947, November 2012
How to Cite
Froriep, U. P., Kumar, A., Cosandier-Rimélé, D., Häussler, U., Kilias, A., Haas, C. A. and Egert, U. (2012), Altered theta coupling between medial entorhinal cortex and dentate gyrus in temporal lobe epilepsy. Epilepsia, 53: 1937–1947. doi: 10.1111/j.1528-1167.2012.03662.x
- Issue published online: 12 NOV 2012
- Article first published online: 17 SEP 2012
- Accepted July 27, 2012; Early View publication September 17, 2012.
- Phase shift;
- Coupled networks;
Purpose: Temporal lobe epilepsy is often accompanied by neuron loss and rewiring in the hippocampus. We hypothesized that the interaction of subnetworks of the entorhinal–hippocampal loop between epileptic events should show significant signatures of these pathologic changes.
Methods: We combined simultaneous recording of local field potentials in entorhinal cortex (EC) and dentate gyrus (DG) in freely behaving kainate-injected mice with histologic analyses and computational modeling.
Key Findings: In healthy mice, theta band activity was synchronized between EC and DG. In contrast, in epileptic mice, theta activity in the EC was delayed with respect to the DG. A computational neural mass model suggests that hippocampal cell loss imbalances the coupling of subnetworks, introducing the shift.
Significance: We show that pathologic dynamics in epilepsy encompass ongoing activity in the entorhinal-hippocampal loop beyond acute epileptiform activity. This predominantly affects theta band activity, which links this shift in entorhinal-hippocampal interaction to behavioral aspects in epilepsy.