Size of CA1-evoked synaptic potentials is related to theta rhythm phase in rat hippocampus

Bradley P. Wyble, Christiane Linster, Michael E. Hasselmo

Research output: Contribution to journalArticlepeer-review

62 Scopus citations


Cholinergic and GABAergic neurons projecting to the hippocampus fire with specific phase relations to theta rhythm oscillations in the electroencephalogram (EEG). To determine if this phasic input has an impact on synaptic transmission within the hippocampus, we recorded evoked population excitatory postsynaptic potential (EPSPs) during different phases of theta rhythm by using techniques similar to those described in Rudell and Fox. Synaptic potentials elicited by stimulation of region CA3 of the contralateral hippocampus were recorded in region CA 1 and CA3. In these experiments, the initial slope of evoked potentials showed a change in magnitude during different phases of the theta rhythm recorded in the dentate fissure, with individual trials showing an average of 9.5% change in slope of potentials, and the average across all experiments showing a change of 7.8%. Evoked potentials were maximal 18°after the positive peak of the dentate fissure theta EEG. These potentials were also smaller by 18.2% during theta as opposed to non-theta states. Phasic changes in modulation of synaptic transmission could contribute to phase precession of hippocampal place cells and could enhance storage of new sequences of activity as demonstrated by computational models.

Original languageEnglish (US)
Pages (from-to)2138-2144
Number of pages7
JournalJournal of neurophysiology
Issue number4
StatePublished - 2000

All Science Journal Classification (ASJC) codes

  • General Neuroscience
  • Physiology


Dive into the research topics of 'Size of CA1-evoked synaptic potentials is related to theta rhythm phase in rat hippocampus'. Together they form a unique fingerprint.

Cite this