The body’s longest nerve, the vagus nerve, is the autobahn between what scientists have referred to as the “two brains” — the one in your head and the other in your gastrointestinal tract. The nerve is key for telling you the tank is full and to put the fork down because it helps transmit biochemical signals from the stomach to the most primitive part of the brain, the brainstem.
But in this animal study, researchers may have found a greater purpose behind this complex circuitry involving the vagus nerve. This “gut-brain axis” may help you remember where you ate by directing signals to another part of the brain, the hippocampus, the memory center.
Following our stomach
The scientists believe that this gut instinct, this connection between spatial awareness and food, is likely a neurobiological mechanism that dates back ages to when the definition of fast food was a herd of deer running away from the nomadic hunters who tracked them.
Back then especially, it would be critical for the gut to work with the brain like a Waze or Google Maps navigation app, said Scott Kanoski, an assistant professor of biological sciences at USC Dornsife and corresponding author of the paper. Those wandering early humans could remember a site where they had found and collected food and return repeatedly for more.