That gut feeling!

Rachel Hosie

Researchers have discovered why we’re able to remember the setting of certain meals in perfect detail — yet often forget important dates, names or where we left our charger.

A new study conducted by the University of Southern California has found that it’s all down to the body’s longest nerve, the vagus nerve, which is the link between the brain and your enteric nervous system. Found in the gastrointestinal tract, it is known as the ‘second brain.’ It sends and receives impulses, responds to emotions and records experiences. 

The vagus nerve is responsible for telling our brains that we feel full after eating, but the new study has found that it also helps us remember details of what and where we ate by sending signals to the hippocampus, which is the area of the brain associated with memory.

The researchers believe this ‘gut-brain axis’ developed to help our ancestors remember where they’d previously found food. For hunter-gatherers, this neurobiological mechanism was crucial when food sources were scarce and they needed to return to bountiful locations. “When animals find and eat a meal, for instance, the vagus nerve is activated and this global positioning system is engaged,” said study co-author Scott Kanoski. 

The study was conducted on rats. It discovered that rats with their gut-brain vagus nerve pathway disconnected could not remember environmental information. “We saw impairments in hippocampal-dependent memory when we cut off the communication between the gut and the brain,” said lead author Andrea Suarez, a PhD candidate in biological sciences.

 — The Independent