- Aging alters gut bacteria in mice, which weakens vagus nerve signaling between the intestines and brain, leading to memory decline.
- Restoring gut-brain communication via vagus nerve stimulation improved memory in older mice to levels seen in young mice.
- The gut microbiome changes with age, with increased Parabacteroides goldsteinii linked to inflammation and reduced hippocampal activity.
- Shared housing experiments showed young mice exposed to old microbiomes performed worse on memory tests, while antibiotics reversed cognitive decline in these mice.