Bursting and Oscillations in a Biophysical Model of Hippocampal Region CA3: Implications for Associative Memory and Epileptiform Activity

  • Gene V. Wallenstein
  • Michael E. Hasselmo


A detailed biophysical model of hippocampal region CA3 was used to show how septal cholinergic and GABAergic modulation, through three distinct mechanisms, interacts with intrinsic and synaptic conductances to influence population behavior. A dissection of each mechanism demonstrates a continuum of population firing activity ranging from fully-synchronized behavior to a mixture of repetitive bursting and oscillations in reduced subsets of neurons, ideal for forming accurate associations during a learning and recall task. Rhythmic modulation (GABAergic) is shown to play a role in the formation of place fields and the model’s capacity for learning sequence information. Such modulation is also shown to account for the phase precession of place units relative to the theta rhythm as an organism passes through the associated place field of the cell.


Pyramidal Cell Theta Rhythm Place Field Biophysical Model Perforant Path 
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Copyright information

© Springer Science+Business Media New York 1997

Authors and Affiliations

  • Gene V. Wallenstein
    • 1
  • Michael E. Hasselmo
    • 1
  1. 1.Department of Psychology and Program in NeuroscienceHarvard UniversityCambridgeUSA

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