A recent study carried out by the University Of Southern California showed why and how are the memory and learning processes influenced by what we eat. A healthy gut, commonly nicknamed the “second brain,” means a healthy brain, and according to this, the scientists found that the gut-brain link influences memory and learning.
A large mesh of neurons exists in the gastrointestinal tract, commonly dubbed as the “second brain.” These gut neurons are linked to the brain through the vagus nerve which was found to establish a metabolic link between intestines and brain.
Signals from the gastrointestinal system travel via the vagus nerve to the brain, signaling us the satiety feeling, making us stop eating when we’re full. However, the researchers from the University Of Southern California tried to notice if there is another link between gut and brain, beyond the metabolic communications.
The gut-brain link influences memory and learning
The scientists eliminated about 8% of the vagus nerve signaling between the gut and the brain in lab rodents models but without altering the metabolic communications. This experiment made it possible for the researchers to observe an intriguing fact. Namely, the rodents weren’t any more capable of accessing spatial and episodic memory, otherwise caused by the digestive system.
The researchers theorized that the guts are indeed the “second brain” because, in the absence of a fully working gut-brain link, memory and learning processes will be impaired.
“When the animals find and eat a meal, for instance, the vagus nerve is activated, and this global positioning system is engaged. It would be advantageous for an animal to remember their external environment so that they could have food again,” explained Scott Kanoski, the study’s author.
In humans, this gut-brain link is an ancient mechanism to help ancient humans remember where good food sources are located and to learn how they could go there and back to their camp.
In conclusion, the researchers from the University Of Southern California warned that weight loss surgeries (bariatric, digestive bypass) and some treatments are effective because they disrupt the gut-brain link conducted via the vagus nerve but they also influence the memory and learning negatively.