Eating bacteria 'can boost brain power'

London: Eating bacteria could boost brain power, according to a new study in mice.

Scientists have carried out the study and found that mice given peanut butter laced with a common, harmless soil bacterium learnt to ran through mazes twice as fast and even enjoyed doing so, the 'New Scientist' reported.

A team, led by Dorothy Matthews of the Sage Colleges in Troy, New York, laced the treat with a tiny bit of Mycobacterium vaccae, and found that the mice ran through the maze twice as fast as those given plain peanut butter.

"This suggests that they had learned to navigate the maze faster," Matthews said.

Moreover, the mice given the bacteria continued to run the maze faster than those without it for 18 more trials over the next six weeks, showing they weren't just made more alert by a surprise change to their treat.

This effect lasted for four weeks after the last piece of doctored peanut butter was given to the mice.

According to the scientists, this was caused by the effect M. vaccae has on the immune system, something that was investigated in 2007 by a team, led by Chris Lowry, now at the University of Colorado at Boulder.

The bacteria may speed up learning because the Raphe nuclei stimulate a brain region called the hippocampus, which handles spatial memory, Matthews said.

But the bacteria also changed the mice's mood - they showed less behaviour that indicates anxiety, such as grooming and searching, perhaps analogous to the calmer behaviour immune activation triggers in people.

This is likely to have been caused by changes to the higher mental functions in the forebrain, which perhaps allowed them to focus better on the maze.

Matthews said that exposure to soil bacteria may affect human brains too. "It just shows that we evolved with dirt as hunter-gatherers. So turn off your TV and go work in your garden, or walk in the woods."