A study published in Evolution & Human Behavior looked at the stress hormone levels of teenaged girls who were stressed to see if there would be any difference between getting a supportive text from their mother and hearing their mother’s voice on the telephone. I think we all know the answer to that one.
The study featured 68 girls between the ages of 7 and 12. They were instructed to give a talk and solve math problems “in front of an audience trained to maintain a neutral facial expression.” After this stress-inducing 15-minute session, University of Wisconsin-Madison cultural anthropologist Leslie Seltzer, and her colleagues found that comforting spoken words from their mothers indeed decreased levels of cortisol (a biomarker of stress) and increased levels of oxytocin (a hormone linked to trust and kindness.)
Furthermore, it seems that moms are not silly when they talk to their babies while they are pregnant. That same voice that will hopefully soothe an anxious teen, is reconized right off the bat in new babies. According to Canadian researchers, by placing electrodes on the heads of 16 infants they were able to show that their mother’s voice was indeed “special” for these babies.
The tests were carried out while the infants were sleeping. Each of the mothers was asked to make a short sound including the vowel A. The same steps were then repeated, but this time the voice the baby heard was that of a nurse. The results? When the mother’s spoke, there were reactions in the left side of the brain that is associated with linguistics and processing. Whereas, when the nurse spoke, the reactions were found the right hemisphere that is associated more with simply vocal recognition. It’s as if when a baby hears his mother, he is receptive to communication and when he hears a stranger, he simply tries to figure out who is making the sounds.