Excess activity shrinks blood vessels in baby mouse brains

Baby mice exposed to excess exercise, whisker-touching or sound had smaller, less-developed blood vessels in the brain, changes that could impair the animals' nervous system.

Lisa Roe/FLICKR

Newborn mouse pups experience permanent brain changes when repeatedly overstimulated.

Researchers stimulated young mice pups by excessively touching the pups’ whiskers, prolonging treadmill sessions or playing chronic noise. When stimulated in one of these ways for five days or longer, the mice’s brains had smaller, less-branched blood vessels.

If the overstimulation lasted longer than a month, the effects were permanent. The changes could deliver less oxygen to the brain and alter the way the animals’ nerve cells work, the team reports December 4 in Nature.

Similar effects could happen in overstimulated human infants, leaving individuals more prone to hypertension, diabetes and aging. But more research needs to be done to determine if the effects observed in mice occur in humans, the scientists note.

Ashley Yeager is the associate news editor at Science News. She has worked at The Scientist, the Simons Foundation, Duke University and the W.M. Keck Observatory, and was the web producer for Science News from 2013 to 2015. She has a bachelor’s degree in journalism from the University of Tennessee, Knoxville, and a master’s degree in science writing from MIT.