Your gut may help your brain decide what to remember

New research from USC finds that the gut helps the brain decide which memories to keep — especially those tied to food. Signals from the digestive system travel through the vagus nerve, triggering acetylcholine release in the hippocampus, which strengthens food-related memories. Notably, nutritional value — not sweetness — drives this response. Long-term unhealthy diets weaken this pathway, potentially linking poor nutrition to cognitive decline and even Alzheimer's disease.