Mothers can pass along their experiences to their children without even trying, researchers reported in a surprising study on Tuesday that showed baby mice could inherit the benefits of "education" that their mothers received before they became pregnant.

Mothers can pass along their experiences to their children without even trying, researchers reported in a surprising study on Tuesday that showed baby mice could inherit the benefits of "education" that their mothers received before they became pregnant.

The study shows that inheritance can go far beyond the classic genetic theories, researchers report in The Journal of Neuroscience.

They found that young mice raised in an enriched environment -- with toys and other stimulation -- passed along the learning benefits to pups they had after they grew up.

The stimulated mothers did not simply have better parenting skills, because the researchers showed pups swapped at birth still learned better if their biological mothers - but not their foster parents - had been raised with the extra toys.

"You inherit to some degree some aspects of your parent's experience," Larry Feig, a professor of biochemistry at Tufts University School of Medicine in Boston, said in a telephone interview.

"This is a protective mechanism a mother passes on to her offspring," Feig, who helped lead the study, added.

Feig and colleagues raised mice, some in plain cases with wood chips and others in "enriched" cages with boxes, a running wheel, toys, and constant rearrangements of nesting material.

They tested learning with an unpleasant "shock chamber" to condition the mice to be afraid.

Mice born to mothers raised in the "enriched" cages learned much more quickly that the shock chamber was a scary place, Feig's team found. This was true even when the mothers did not become pregnant until weeks after they lived in the special cages.