Low-Frequency Oscillatory-Mediated Olfactory Bulb-to-Prefrontal Cortex Communication During Anxiety-Like States

Author
A. Samii Moghaddam
School of Medicine, Zahedan University of Medical Sciences, Zahedan, Iran.
Abstract
Abstract

Introduction: Anxiety disorders affect nearly one-third of adults worldwide and are associated with complex neural circuitry that remains incompletely understood. This study investigates the directional information flow between the olfactory bulb (OB) and medial prefrontal cortex (mPFC) during anxiety-like states.

Methods: Local field potentials (LFPs) were recorded simultaneously from OB and mPFC in male Wistar rats during Elevated Plus Maze (EPM) and Open Field (OF) tasks. Granger causality analysis was applied to assess directional information flow across delta (1–4 Hz), alpha (8–12 Hz), and beta (13–30 Hz) frequency bands.

Results: The analysis revealed a consistent pattern of bottom-up information transfer from OB to MPFC, with significantly stronger Granger causality in the OB→mPFC direction compared to mPFC→OB across all frequency bands. This pattern indicates a dominant feedforward flow of information during anxiety states.

Conclusion: These findings demonstrate that the OB-mPFC axis operates through synchronized low-frequency oscillations, forming a hierarchical network during threat processing.

Keywords

Subjects

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