Babies can learn very early in life to fear something that frightened their mothers even before they were born. Scientists have known for some time that trauma can ripple through generations. Emotional trauma is transmitted across generations. For example, children witnessing their parent expressing fear to specific sounds or images begin to express fear to those cues. Within normal range, this is adaptive, although pathological fear, such as occurs in posttraumatic stress disorder or specific phobias, is also socially transmitted to children and is thus of clinical concern. New research on fear transmission may help explain how that happens.
“Our research demonstrates that infants can learn from maternal expression of fear very early in life,” said Jacek Debiec, MD, PhD, the psychiatrist and neuroscientist who led the research. “Before they can even make their own experiences, they basically acquire their mothers’ experiences. Most important, these maternally transmitted memories are long-lived, where other types of infant learning, if not repeated, rapidly perish.”
Jacek Debiec recalls working with adult children of Holocaust survivors who had nightmares and flashbacks related to experiences they had not endured themselves. Rachel Yehuda, a psychiatrist at Mount Sinai Hospital in New York, has studied descendants of Holocaust survivors and the children of women who were pregnant and in or near the World Trade Center on 9/11/2001. She found evidence of intergenerational trauma transmission that could not have occurred through storytelling. She said understanding the brain changes that occur with intergenerational transmission could help people understand the long-term impact of parental experiences. “Your fears are not only a response to your personal experiences,” Yehuda told Verge, “but those that your parents had as well.”