, Volume 4, Issue 1, pp 1–10 | Cite as

Fast network oscillations in the hippocampus

Phenomena, mechanisms and open questions at the interface of cellular and systemic neurosciences
Review article


Neuronal networks often express coherent oscillatory activity. These rhythms can provide a temporal reference for the activity of single neurons and allow the formation of spatiotemporal activity patterns with a defined phase relationship of action potentials. In a single brain nucleus, oscillations at different frequencies might be simultaneously generated, but isolated rhythms might also be characteristic for specific functional brain states. During the last two decades the mammalian hippocampus has become an important model system for the study of neuronal network oscillations. In this brain area, cellular mechanisms underlying neuronal synchronization have been described, but also models were developed to explain the contribution of oscillations in encoding, consolidation, and recall of memories. Neuronal rhythmic activities provide an important field of analysis bringing together cellular mechanisms and systemic functions of the brain. Here, we use a particularly fast type of neuronal oscillation, hippocampal “ripples”, as an example to outline current knowledge and open questions related with this research field.


Neuronal network oscillation Learning and memory Hippocampus Cellular mechanisms Ripples 


Conflict of interest

On behalf of all authors, the corresponding author states that there are no conflicts of interest.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2013

Authors and Affiliations

  1. 1.Neurowissenschaftliches Forschungszentrum der CharitéCharité-Universitätsmedizin BerlinBerlinGermany
  2. 2.Institut für Physiologie und PathophysiologieMedizinische Fakultät der Universität HeidelbergHeidelbergGerman

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