Can bacteria make you smarter?

Exposure to specific bacteria in the environment, already believed to have antidepressant qualities, could increase learning behavior according to research presented today at the 110th General Meeting of the American Society for Microbiology in San Diego.

"Mycobacterium vaccae is a natural which people likely ingest or breath in when they spend time in nature," says Dorothy Matthews of The Sage Colleges in Troy, New York, who conducted the research with her colleague Susan Jenks.

Previous research studies on M. vaccae showed that heat-killed injected into mice stimulated growth of some neurons in the brain that resulted in increased levels of and decreased .

"Since serotonin plays a role in learning we wondered if live M. vaccae could improve learning in mice," says Matthews.

Matthews and Jenks fed live bacteria to mice and assessed their ability to navigate a maze compared to control mice that were not fed the bacteria.

"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," says Matthews.

In a second experiment the bacteria were removed from the diet of the experimental mice and they were retested. While the mice ran the maze slower than they did when they were ingesting the bacteria, on average they were still faster than the controls.

A final test was given to the mice after three weeks' rest. While the experimental mice continued to navigate the maze faster than the controls, the results were no longer statistically significant, suggesting the effect is temporary.

"This research suggests that M. vaccae may play a role in anxiety and learning in mammals," says Matthews. "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."

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Provided by American Society for Microbiology
Citation: Can bacteria make you smarter? (2010, May 24) retrieved 18 October 2019 from
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May 24, 2010
Very interesting, I remember being puzzled by an observational study a while back which linked happiness to working outdoors (particularly around earth, plants, etc), it's nice to have a more precise reason.

May 25, 2010
That is interesting... here in Czech preschoolers pretty often work and play in the gardens and it is almost always obvious that those kids are then more rested and can focus better on learning. Simple hobby of gardening could be then prescribed as form of relaxation, not only you can see and learn how nature works its miracles, you are also inhaling and ingesting these bacteria... nice

May 25, 2010
This really deals with a much a larger issue that has been largely ignored. Our biological systems are complex and highly evolved. We, organizums, are all part of the same dead star, we all evolved together, interacting and evolving with each other directly. You cannot expect to know all the aspects of 4 billion years worth of complex evolution, and if you can't know, you cannot by any means expect to improve on it.

This article is only proves, in a general sense, that humans natural behavior is greately affected, negatively for a large magority of the time, by the conditions we create.

Other examples of problems where we are negitively affecting our behavior and life: pollution, processed foods. God knows what the long term effects will be.

May 25, 2010
SO How are we to know if this same bacterium is present in our soil ?

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