Event:

"The prefrontal cortex (PFC) is a 130 year old concept. Although this part of cortex still lacks a conclusive definition, a reoccurring proposition holds that the PFC is central to the temporal organization of behavior. Attention plays a crucial role in our ability to organize thoughts and actions in meaningful behavior, and the PFC directly influences attentional processing. Using in vivo recordings and optogenetics in freely moving mice we could recently show that local fast-spiking inhibitory interneurons expressing parvalbumin (PV) are central to PFC’s control of attention. During successful allocation of attention PV neurons in the medial PFC (mPFC) become strongly synchronised, which is accompanied by an increase in gamma oscillations and gamma-phase-dependent rate modulation of local pyramidal neurons. In essence, the fast-spiking PV neurons act as a functional unit coordinating the activity in the local mPFC circuit during goal-driven attentional processing. Appropriate optogenetic activation of mPFC PV neurons improves goal-directed behaviour. I will discuss our findings, and the implicated functional role of PV interneurons and gamma oscillations in cognition.

Similarities is connectivity is a suggested criteria for establishment of cortical homologies across species. Retrograde monosynaptic rabies tracing has rapidly become widely used for circuit interrogations in mice, enabling whole-brain mapping of the input to a neuronal population of choice. We have traced the input to four different neuronal populations in the PFC (PV, SOM, VIP, CamKIIa-expressing neurons, respectively). I will discuss our findings in relation to the function of the PFC, in mice and across species. I will in addition highlight important, but often overlocked, caveats in rabies tracing studies".