Olfactory bulb-medial prefrontal cortex circuit slow oscillations encode working memory representations

Working memory (WM), the ability to maintain task-related information, is fundamental to animal behaviors. Despite significance, there is limited knowledge on how it is orchestrated by the neural activity in the brain. Here, we show that the olfactory bulb (OB) and medial prefrontal cortex (mPFC) slow oscillations (1-30 Hz) are augmented during WM, and furthermore, the pattern of these activities convey task-related information. Moreover, we find that the OB-mPFC delta and beta power-based connectivity is enhanced by WM. On the other hand, theta oscillations have the most prominent roles in phase coupling in this circuit. We also show bidirectional information transfer, stronger in the mPFC-to-OB direction, between the two brain areas. Furthermore, during WM, beta activity in both regions is tuned by the phase of local and long-range delta as well as theta oscillations. Together, our results suggest that the dynamics of OB-mPFC circuit slow band activities underlies WM, with possible implications for other cognitive functions in health and disease.