The Papez circuit of the brain is one of the major pathways of the limbic system and is chiefly involved in the cortical control of emotion. The Papez circuit plays a role in storing memory.
Described by James Papez in 1937, Papez discovered the circuit after injecting rabies virus into a cats hippocampus and monitoring its progression through the brain. The initial pathway was described as follows:
Since then, new findings in neuroanatomy and brain function by Paul D. MacLean and others have elucidated a larger circuit that also includes the prefrontal cortex (PFC), amygdala, and septum among other areas. The PFC and amygdala are key components in this larger loop.