Pacifiers impair social responses in boys

Baby boys who use pacifiers fail to mimic the facial expressions of adults and other children, which in turn impairs learning social and emotional responses to other human beings, according to research that explored the relationship between pacifier use and emotional development in children.

Researchers conducted 3 investigations to examine the effects of pacifiers on social processing skills during infancy.

In 1 study, the parents of first- and second-grade students in 4 elementary schools in France completed questionnaires assessing their children’s pacifier use and thumb sucking, specifically the age in months at the onset and the ending of the practice, when and where their children used pacifiers, and the frequency of use.

The children were administered a “morphing” task in which they mimicked sad or smiling faces presented on a computer screen while they were filmed and their responses scored. Results showed that boys who had used pacifiers frequently during the day at home were less likely to copy the facial expressions onscreen.

In a second study, researchers surveyed 167 college students who had used pacifiers as children for an average duration of 22 months. The men in the study who had used pacifiers more often as babies scored lower on tests of perspective taking, which is related to empathy.

The third study compared scores on emotional intelligence tests among 124 college students from the United States and 304 university students from France. The men in both groups who had most used pacifiers scored lower for emotional competence, showing that the detrimental effect of pacifier use among boys is not specific to country.

In all 3 studies, the effect was noticeably absent among girls. Also, none of the studies produced the same effect for thumb sucking.

The findings that only boys show impaired emotional functioning because they used pacifiers as infants suggests that perhaps boys are more immature and also more vulnerable than girls to disruptions in social information processing early in life. Babies with pacifiers in their mouths cannot easily copy the facial expressions of caregivers or other children, making it more difficult for them to express their own emotions in response.

The American Academy of Pediatrics, however, recommends using pacifiers at night and during all sleep times because studies have shown that pacifiers reduce the risk of sudden infant death syndrome.

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