Bacteria in Gut Affect Development and Behaviour

The teeming trillions of bacteria in the digestive tracts of mice have been shown to affect the animals' brain development and behaviour. Mice bred in sterile environments without these "gut flora" were seen to be more adventurous and less anxious than mice with normal gut flora.

The research adds weight to the idea that gut bacteria are a critical part of the overall development of mammals. The study is published in Proceedings of the National Academy of Sciences.

Gut flora were once thought to be harmless residents of the guts of mammals, and in time it became clear that they not only aid in digestion but also protect against the arrival of more harmful invaders. But research in recent years has shown an increasingly complex picture in which the bugs play significant roles in several critical bodily systems, having already been implicated in obesity, asthma, and liver function.

from BBC News Online