MADISON Pacifiers may stunt the emotional development of baby boys by robbing them of the opportunity to try on facial expressions during infancy.
Three experiments by a team of researchers led by psychologists from the University of WisconsinMadison tie heavy pacifier use as a young child to poor results on various measures of emotional maturity.
The study, published today by the journal Basic and Applied Social Psychology, is the first to associate pacifiers with psychological consequences. The World Health Organization and American Academy of Pediatrics already call for limiting pacifier use to promote breast-feeding and because of connections to ear infections or dental abnormalities.
Humans of all ages often mimic unwittingly or otherwise the expressions and body language of the people around them.
"By reflecting what another person is doing, you create some part of the feeling yourself," says Paula Niedenthal, UWMadison 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 can be an important learning tool for babies.
"We can talk to infants, but at least initially they aren't going to understand what the words mean," Niedenthal says. "So the way we communicate with infants at first is by using the tone of our voice and our facial expressions."
With a pacifier in their mouth, a baby is less able to mirror those expressions and the emotions they represent.
The effect is similar to that seen in studies of patients receiving injections of Botox to paralyze facial muscles and reduce wrinkles. Botox users experience a narrower range of emotions and often have trouble identifying the emotions behind expressions on other faces.
"That work got us thinking about critical peri
|Contact: Paula Niedenthal|
University of Wisconsin-Madison