The study was the first to examine the brain function of grandmothers. It was published last month in Proceedings of the Royal Society B.
In the study, 50 participants filled out surveys about their experiences as grandmothers. They shared details including the amount of time they spend with their grandchildren, joint activities and how much affection they feel for them.
Functional magnetic resonance imaging (fMRI) was conducted on participants. It measured their brain function as they viewed pictures of their grandchild, an unknown child, the same-sex parent of the grandchild and an unknown adult.
“What really jumps out in the data is the activation in areas of the brain associated with emotional empathy,” lead author James Rilling, Emory professor of anthropology, said in a press release. “That suggests that grandmothers are geared toward feeling what their grandchildren are feeling when they interact with them. If their grandchild is smiling, they’re feeling the child’s joy. And if their grandchild is crying, they’re feeling the child’s pain and distress.”
When grandmothers view an image of their adult child, they show stronger activity in an area of the brain associated with cognitive empathy. The indication is that grandmothers may be attempting to cognitively understand what their adult child is thinking or feeling. They may also be trying to understand why their adult child is feeling that way. But not as much from the emotional side.
“Young children have likely evolved traits to be able to manipulate not just the maternal brain, but the grand maternal brain,” Rilling said. “An adult child doesn’t have the same cute ‘factor,’ so they may not (elicit) the same emotional response.”
“Our results add to the evidence that there does seem to be a global parenting caregiving system in the brain, and that grandmothers’ responses to their grandchildren (map) onto it,” Rilling said.
Study coauthor Minwoo Lee, a Ph.D. candidate in Emory’s Department of Anthropology, said it’s relatively rare for scientists to conduct a study of the older human brain that isn’t about aging disorders, such as dementia.
“Here, we’re highlighting the brain functions of grandmothers that may play an important role in our social lives and development,” Lee said. “It’s an important aspect of the human experience that has been largely left out of the field of neuroscience.”
To get specialized news and articles about aging in place, health information and more, sign up for our Aging in Atlanta newsletter.