[Δ-, θ-Modulation of the Ventral Tegmental Area Fast-Gamma Activity in the Course of Performance of Conditioned Avoidance Reflex in Rat].
The prestimulus expectation period of conditioned avoidance reflex features synchronized Δ-rhythm (1-4 Hz) in the medial prefrontal cortex and the ventral tegmental area (VTA), and synchronized θ-rhythm (6-8 Hz) in the above-mentioned structures and the hippocampus. According to "Granger causality" Δ- and θ-rhythms flow (are predictors) in the direction from the prefrontal cortex and the hippocampus to the VTA. Performance of conditioned avoidance reflex was marked by Δ-rhythm elimination simultaneously with generation of high-frequency (8-11 Hz) synchronized θ-rhythm. Δ-rhythm was shifted from the pre- to poststimulus period and prefrontal cortex--VTA θ-synchrony was eliminated in the cases of mistaken reaction withdrawal, Pavlovian fear conditioning scheme, conditioned signal presentation in the safe chamber part. The phase of Δ-, θ-rhythm modulates the amplitude of VTA fast (70-160 Hz) γ-activity envelope, VTA/cortex and VTA/hippocampus γ-phase synchronization and phase lag indexes, and frequency of simultaneously recorded VTA neuronal activity.
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Serkov
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Maiorov
D000818:Animals; D001362:Avoidance Learning / Q000502:physiology*; D003214:Conditioning, Classical / Q000502:physiology*; D003700:Delta Rhythm / Q000502:physiology; D065818:Gamma Rhythm / Q000502:physiology; D006624:Hippocampus / Q000502:physiology*; D008297:Male; D009474:Neurons / Q000502:physiology; D017397:Prefrontal Cortex / Q000502:physiology*; D051381:Rats; D017208:Rats, Wistar; D013826:Theta Rhythm / Q000502:physiology; D017557:Ventral Tegmental Area / Q000502:physiology*