Remember the best burger of your life? The blast of fat in your mouth, the molten American cheese, the crunch of the lettuce, the unparalleled satisfaction of that very first bite and the juice dribbling down your chin? You can still taste it now, right?
This is why.
Earlier today, we learned that deep within your ass — more accurately, in your gut — there lies a “second brain.” Well, not a brain, per se, but “an autonomous matrix of millions of neurons” that controls your digestive tract on a subconscious level and ensures food progresses its way through your intestine, steadily and without conflict.
But new research shows that the “gut-brain axis” (as medical researchers call it) runs even deeper. It’s your gut, not your head, that’s responsible for making food so memorable.
Everyone has certain food memories — bites of pizza, chomps of sandwiches or spoonfuls of ice cream that were so indelibly delicious that they can recall the exact circumstances under which they consumed them (e.g., the restaurant, the people they were with, what was said). And this memory is created in your stomach, it seems, not your brain, according to a new study from researchers at the University of Southern California.
The connection is made by the vagus nerve, the longest nerve in the human body, running from the complex tangle of neurons in your intestines to your brain. And when you eat an especially memorable piece of food, the vagus nerve delivers a message directly from your stomach to the hippocampus—the brain’s memory center—telling you that this is a meal you will daydream about in the future. (And if you’ve ever called a bite “orgasmically good,” know that in women, the vagus nerve also plays a part in orgasm.)
The evolutionary-psychology explanation for this phenomenon is that it’s a holdover from our hunter-gatherer days, and thus, encoded in our lizard brains. Primitive humans needed to remember where they could find sustenance, so their bodies developed a neural pathway designed to remind them where they had eaten that delicious slab of mastodon rib.
In addition to explaining why there are certain dishes that hold a particularly large piece of real estate in your mind, the study also speaks to the almighty power of the vagus nerve, which sends messages to nearly every bodily organ. Your vagus nerve is tasked with helping your body relax during high-stress situations, and it can be activated by taking a particularly large shit.
Ah, the poetic beauty of a nerve that creates lasting memories as objects enter and exit our mortal frame.