Sucking on a pacifier may stop a baby’s complaints, but for boys it can also slow their emotional development.
Researchers from the University of Wisconsin-Madison have found that heavy pacifier use as a child for boys has a direct link to poor results in various measures of emotional maturity later in life. The baby brain learns much about emotions by mimicking facial expressions. Apparently, for boys, too much pacifier use can slow this mimicking process down enough to derail emotional development.
“By reflecting what another person is doing, you create some part of the feeling yourself,” says Paula Niedenthal, UW–Madison psychology professor and lead author of the study. “That’s one of the ways we understand what someone is feeling — especially if they seem angry, but they’re saying they’re not; or they’re smiling, but the context isn’t right for happiness.”
Mimicry, notes the research published in Basic and Applied Psychology, is an important learning tool for children. The scientists found that adults who had spent the most time with pacifiers in their mouths as children often exhibited the same lack of facial emotional expression as people that had undergone facial-paralyzing Botox injections.
The researchers did not find the same outcomes in girls, possibly because of faster emotional development.
“There’s no effect of pacifier use on these outcomes for girls, and there’s a detriment for boys with length of pacifier use even outside of any anxiety or attachment issues that may affect emotional development,” says Niedenthal.
The researchers contend that not all pacifier use is bad — for example at night when there is no one to mimic. They recommend, however, that parents make a conscious effort to avoid the pacifier during waking hours because so much of an infant’s ability to communicate is related to facial expression.