Pacifiers inhibit emotional growth in boys, US studies suggest
Research shows less tendency to mimic frowns and smiles among male children
You may want to think twice before sticking that pacifier back in your baby boy's mouth. Three new studies, published as a single research report, find that heavy pacifier use leads to stunted emotional development among males.
The researchers, led by scientists from the University of Wisconsin, did not spend the years it would take to track a single group of children from infancy to adulthood. Instead, they conducted three separate experiments that attempted to get at the same developmental stages.
First, they found that boys aged six and seven who had used pacifiers commonly when they were younger were less likely than other boys to mimic the smiles and frowns of faces on a video screen in front of them - a test of children's interpersonal empathy.
The next two studies used the age-old psychology research study group: college students. The researchers asked the students (who likely asked their parents) how often they used pacifiers when they were little. They then gave the students a test of what's called "perspective taking", which is the ability to assume someone else's point of view and is often stunted in people with autism. Finally, they also gave college students a test of emotional intelligence, which required them to make decisions that relied on understanding the feelings of others.
In both cases, heavy pacifier use was associated with poor scores.
So what's the link?
Infancy is considered a critical period for many human skills and capacities, including emotional and interpersonal development. That means that if we don't have the right exposure or the right experiences when we're little, we may never have them at all. And if infants use pacifiers all the time, they are unable to mimic faces and have social interactions that rely on facial expressions - both believed to be essential building blocks of social and emotional development.
Interestingly, the effect was only found in boys, and the researchers will have to conduct further studies to determine why. One theory is that girls' parents better compensate for the pacifier by engaging with them more emotionally than they do with boys, though it is also possible that girls are inherently better able to cope, the researchers say.