An increasingly popular activity for parents of infants and early childhood education centers is to demonstrate to babies and encourage the use of basic sign language or “baby sign” for words such as “milk” or “hot.” One touted benefit of the practice is the possibility that such activities foster accelerated language development, although this finding is inconsistent and has not been subjected to rigorous evaluation. This study by Kirk and colleagues, recently published in the journal Child Development, is the first randomized controlled study of the impact of infant signing on language development.
Participants included 40 typically developing infants from the age of 8 to 20 months and their mothers. Subjects were randomized to four conditions: baby signing, British sign language and two control conditions, a nonintervention and a verbal training condition. The authors assessed language development using standard measures. In a second study using a subset of the original sample, recorded and coded interactions were used to assess infant-mother relationship qualities at multiple home visits when infants were at ages 10, 12, 16, and 20 months.
Results showed that the program to encourage baby sign did not result in any improved outcomes with regard to spoken language development, although the infants taught gestures generally were able to use them to communicate. There was, however, an indication that a few infants, especially those with lower baseline expressive language, may have benefited more than others. In the second study, significant differences were found in other areas, with mothers who participated in the sign training found to be more attuned to infants’ nonverbal cues and more encouraging of infant autonomy than those in the control group.
The authors concluded that while there was no evidence of accelerated language development with the use of baby signing, benefits were observed for the practice in other areas of the mother-infant relationship.
In light of the expanding market for baby signing classes and products, this study suggest that such things may be unnecessary, at least with regard to typically developing infants and language acquisition. The authors acknowledged some limitations of the study including recruiting a fairly high SES group of mothers and having a small sample size. Thus, it is possible that there may be benefits to the technique but in groups, unfortunately, that are typically less likely to try baby signing in the first place. The bottom line here is that there may be good reasons for parents to want to do some baby signing but giving them a leg up in terms of language development probably isn’t one of them.