Traveling Theta Waves along the Entire Septotemporal Axis of the Hippocampus

A topographical relationship exists between the hippocampus-entorhinal cortex and the neocortex. However, it is not known how these anatomical connections are utilized during information exchange and behavior. We recorded theta oscillations along the entire extent of the septotemporal axis of the hi...

Full description

Saved in:
Bibliographic Details
Main Authors: Patel Jagdish
Fujisawa Shiogeyoshi
Berényi Antal
Royer Sébastien
Buzsáki György
Format: Article
Published: 2012
Series:NEURON 75 No. 3
doi:10.1016/j.neuron.2012.07.015

mtmt:2188080
Online Access:http://publicatio.bibl.u-szeged.hu/11404
Description
Summary:A topographical relationship exists between the hippocampus-entorhinal cortex and the neocortex. However, it is not known how these anatomical connections are utilized during information exchange and behavior. We recorded theta oscillations along the entire extent of the septotemporal axis of the hippocampal CA1 pyramidal layer. While the frequency of theta oscillation remained same along the entire long axis, the amplitude and coherence between recording sites decreased from dorsal to ventral hippocampus (VH). Theta phase shifted monotonically with distance along the longitudinal axis, reaching ∼180° between the septal and temporal poles. The majority of concurrently recorded units were phase-locked to the local field theta at all dorsoventral segments. The power of VH theta had only a weak correlation with locomotion velocity, and its amplitude varied largely independently from theta in the dorsal part. Thus, theta oscillations can temporally combine or segregate neocortical representations along the septotemporal axis of the hippocampus. Patel and colleagues report that the phase of hippocampal theta oscillation and associated pyramidal cell discharge gradually shift ∼180° from the septal to the temporal pole. Therefore, the two poles of the hippocampus tend to send temporally segregated outputs to the neocortex. © 2012 Elsevier Inc.
Physical Description:410-417
ISSN:0896-6273