Interdependence of Multiple Theta Generators in the Hippocampus: a Partial Coherence Analysis

• DOI: 10.1523/jneurosci.19-14-06200.1999
• Publication Date: 2018-04-13T22:21:07Z
• Authors: Bernat Kocsis; Anatol Bragin; György Buzsáki
• Keywords: Entorhinal cortex; Pyramidal cell; Local field potential

The extracellularly recorded theta oscillation reflects a dynamic interaction of various synaptic and cellular mechanisms. Because the spatially overlapping dipoles responsible for generation field may represent different mechanisms, their separation might provide clues with regard to origin significance. We used novel approach, partial coherence analysis, reveal components rhythm relationship among its generators. Hippocampal activity was by 16-site silicon probe in CA1–dentate gyrus axis awake rat. Field patterns, from intrahippocampal or entorhinal cortex sites, were remove caused common source partialization procedure. findings revealed highly coherent coupling between signals (1) hippocampal fissure stratum (str.) oriens CA1 region (2) radiatum dentate molecular layer. results analysis indicated that rhythmic input explained str. but not derived After bilateral lesions cortex, all both below above pyramidal cell layer became coherent. These observations indicate presence two, relatively independent, generators hippocampus, which are mediated CA3–mossy recurrent circuitry, respectively. generator is partially suppressed interneuronal output intact brain. suggest timing action potentials cells during cycle determined cooperation active CA3 neurons input.