Original Baby Signs® Study
Drs. Acredolo and Goodwyn have conducted over two decades of scientific research on the use of sign language with hearing babies, including a longitudinal study funded by the National Institutes of Health. Below are the highlights from that study.
More than 140 families joined the study beginning when their babies were 11 months old. Each family was randomly assigned to a signing or a non-signing group. The groups were equivalent at the beginning of the study in terms of the following characteristics: sex and birth order of the children, their tendency to vocalize or verbalize words, and the parents’ education and income levels.
The children were assessed using standardized language measures at 11, 15, 19, 24, 30, and 36 months old. In addition, as many children as could be relocated at age 8 were assessed using the WISC-III IQ test, the most commonly used measure of children’s intelligence.
Results of the study revealed that 24-month-old babies using baby sign language were on average talking more like 27 or 28-month-olds, representing more than a three-month advantage over the non-signers. The babies using baby sign language were also putting together significantly longer sentences. In addition, 36-month-old signers on average were talking like 47-month-olds, putting them almost a full year ahead of their average age mates. At 8 years, those who had used sign language as babies scored an average of 12 points higher in IQ on the WISC-III than their non-signing peers.
In addition to helping babies learn to talk and jump-starting their intellectual development, a number of very important social-emotional benefits were also revealed. Acredolo and Goodwyn found that signing with hearing babies:
- reduces frustration, biting and other aggressive behaviours.
- helps parents and teachers be more observant and responsive.
- builds trust between babies and their parents and caregivers.
- allows babies to share their worlds revealing just how smart babies really are.
- promotes positive emotional development.
- boosts babies’ self-confidence and builds self-esteem.