Mycobacterium vaccae is a type of bacteria that naturally leaves in soil and has been in the attention of researchers for a while now, due to the fact that it decreases anxiety. Recent studies sugest that in fact, it also stimulates neuron growth and thus intelligence and the ability to learn.

Dorothy Matthews and Susan Jenks from The Sage Colleges in Troy, New York believed this bacteria could have a beneficial impact on neurons too, and injected the bacteria in mice which, at first, led to a significantly increased serotonin production. However, researchers were interested in a more indirect effect.

“Since serotonin plays a role in learning we wondered if live M. vaccae could improve learning in mice.”

In order to assess this assumption, they took two groups and injected only one of them with the bacteria, and then tested them in a maze. The difference was easy to notice.

“We found that mice that were fed live M. vaccae navigated the maze twice as fast and with less demonstrated anxiety behaviors as control mice.”

The mice were then tested after the bacteria was removed from their organisms. When they were tested immediatly afterward, they still did better than their counterparts, but not as good as the first time. Three weeks later, they were tested again. The results were still slightly better, but not statistically relevant. This seems to suggest that the boost to learning is of temporary nature, but applied to humans with a greater cognitive capacity, the results might be more spectacular.

“This research suggests that M. vaccae may play a role in anxiety and learning in mammals. It is interesting to speculate that creating learning environments in schools that include time in the outdoors where M. vaccae is present may decrease anxiety and improve the ability to learn new tasks.”