Stress can lead to a host of health issues, including heart disease, digestive problems, asthma and diabetes. Stress can also be inherited, setting up infants and children for lives of anxiety as a result of stressors their parents faced before they were even conceived.

Fortunately, researchers at Emory University’s Yerkes National Primate Research Center have shown for the first time it is possible to reverse the hereditary influences of parental stress. The findings could lead to treatments to prevent intergenerational stress in humans.

The scientists used two pleasant odors on adult male mice to identify effective strategies to break the cycle of intergenerational stress. They began the study with each mouse participating in one of three protocols: 1) exposed the mice to an odor; 2) trained the mice to associate an odor with a mild stressor; or 3) trained the mice to associate the odor with a mild stressor and then extinguished the fear via extinction training during which the researchers presented the odor in the absence of any stress.

By extinguishing parental fear to the two specific odors, the researchers found three key results: 1) the offspring did not show any behavioral sensitivity to the same two odors; 2) the nervous systems of the offspring did not show any structural imprints of the parental olfactory stress; and 3) the sperm of the parental male mice did not bear chemical imprints of the olfactory stress.

“Our study results not only confirm conditioned stress can be extinguished in the parent without passing it on to the offspring, they are an important public health contribution because they provide optimism for applying similar interventional approaches in humans and breaking intergenerational cycles of stress,” said Brian Dias, an assistant professor at the Yerkes Research Center and the Emory University School of Medicine Department of Psychiatry and Behavioral Sciences. “These latest data provide our research team a platform from which we can address larger public health concerns, including the intergenerational influences of parental neglect and maltreatment during childhood. We want to know whether reversals such as what we showed in our current study can be observed after we apply interventions to populations exposed to these negative environmental influences.”