Circuit organization of the rodent medial prefrontal cortex

Highlights:
The rodent medial prefrontal cortex (mPFC) shows key differences from sensory cortex in the composition and organization of local and long-range circuits.

Long-range inputs from other brain regions display distinct lamination patterns, which contribute to the cellular and subcellular targeting of these projections.

Long-range inputs to the mPFC contact distinct populations of both projection neurons and interneurons, potentially explaining these inputs’ unique behavioral roles.

In many cases, long-range inputs preferentially target neurons that project back to the input region, providing a synaptic substrate for strong reciprocal loops.

Projection neurons and interneurons also make specific local connections that shape how functional signals are routed through the mPFC, linking inputs with outputs.

The prefrontal cortex (PFC) orchestrates higher brain function and becomes disrupted in many mental health disorders. The rodent medial PFC (mPFC) possesses an enormous variety of projection neurons and interneurons. These cells are engaged by long-range inputs from other brain regions involved in cognition, motivation, and emotion. They also communicate in the local network via specific connections between excitatory and inhibitory cells. In this review, we describe the cellular diversity of the rodent mPFC, the impact of long-range afferents, and the specificity of local microcircuits. We highlight similarities with and differences between other cortical areas, illustrating how the circuit organization of the mPFC may give rise to its unique functional roles.