Dr. Linda Acredolo and Dr. Susan Goodwyn, the authors of the book Baby
Signs: How to Talk with Your Baby Before Your Baby Can Talk, have conducted
over two decades of academic research on the use of signs with hearing babies,
including a long-term study funded by the National Institutes of Health. Their
ground-breaking research describes the proven benefits of the Baby Signs®
Program. Their scientific study of over 140 families took place over a
seven-year period and yielded some remarkable results. They conducted
standardized assessments of children who participated in Baby Signs®
groups and
those in non-Baby Signs®
groups at several stages in their development.
- Original
Baby Signs® Study
- Center-based
Research
- Early
Head Start Research
- International
Research
- Annotated
Bibliography
1. 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 signing babies were on average
talking more like 27- or 28-month-olds, representing more than a three-month
advantage over the non-signers. The babies who signed 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 signed 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 jumpstarting their
intellectual development, a number of very important social-emotional benefits
were also revealed. Acredolo and Goodwyn found that signing with hearing babies:
In conclusion, the evidence that the Baby Signs® Program is good
for children, parents, child care providers, and child development centers and
their teachers is tremendously convincing.
5. Bibliography of Baby Signs® Research
For those interested in reading more about the background research concerning
the Baby Signs® Program (known in scholarly journals as
"symbolic gesturing"), the following articles are recommended. These
articles are readily available in libraries.
Susan Goodwyn, Linda Acredolo, and Catherine Brown (2000). Impact of
symbolic gesturing on early language development. Journal of Nonverbal Behavior,
24 (2), pp. 81-103.
Acredolo, L. P., & Goodwyn, S.W. (July 2000). The long-term
impact of symbolic gesturing during infancy on IQ at age 8. Paper presented at
the meetings of the International Society for Infant Studies, Brighton, UK.
Brie Moore, Linda Acredolo, & Susan Goodwyn (April 2001).
Symbolic gesturing and joint attention: Partners in facilitating verbal
development. Paper presented at the Biennial Meetings of the Society for
Research in Child Development.
Linda Acredolo and Susan Goodwyn (1985). Symbolic gesturing in
language development: A case study. Human Development, 28, 40-49.
This article presents the story of our first "Baby Signer," Linda’s
daughter Kate who began to spontaneously create symbolic gestures when she was
about 12 months old. These were "sensible" gestures (like sniffing for
"flower" and arms-up for "big"). We then made it easy for
her by modeling other simple gestures for things in which she was interested and
followed her progress in terms of both gestural and verbal development.
Linda Acredolo and Susan Goodwyn (1988). Symbolic gesturing in normal
infants. Child Development, 59, 450-466.
Our goal in the two separate studies described in this article was to learn more
about the spontaneous development of symbolic gestures by infants. Was Linda’s
daughter alone in doing so (see Acredolo & Goodwyn, 1985) or were other
babies as creative as Kate? The answer was extremely clear. Although Linda was a
bit disappointed to learn that Kate was not totally unique, she quickly became
excited to see that most babies create at least one or two such symbolic
gestures and that some children, like Kate, create many. The article also
describes (a) relations with verbal development, (b) the sources of the gestures
in the babies’ everyday lives, (c) and gender and birth order differences.
Linda Acredolo and Susan Goodwyn (1990). The significance of symbolic
gesturing for understanding language development. In R. Vasta (Ed.), Annals of
Child Development (Vol. 7, pp. 1-42). London: Jessica Kingsley Publishers.
Readily
This invited chapter provided an opportunity for us to review the role that
symbolic gestures, including formal sign language systems such as ASL, seem to
play in the development of verbal language in hearing children. We describe many
classic case studies (e.g., Holmes & Holmes, 1980 and Prinz & Prinz,
1979) in addition to our own work and identify common denominators among them.
The final discussion addresses the question of whether certain early milestones
of language development (e.g., first true symbol, first two symbol combinations)
are more easily achieved in the gestural than in the verbal modality.
Susan Goodwyn and Linda Acredolo, (1993). Symbolic gesture versus
word: Is there a modality advantage for onset of symbol use? Child Development,
64, 688-701.
The results reported in this article represent some of the earliest findings
from our NIH-sponsored longitudinal study of the impact of purposefully
encouraging babies to use symbolic gestures. The goal was to shed light on a
hotly debated topic: the degree to which gestural symbols represent an easier
entrée into symbolic communication.
Linda Acredolo, L. P., & Goodwyn, S.W. (1997). Furthering our
understanding of what humans understand, Human Development, 40, 25-31.
Because we had done so much work in the area of children and symbolic gesturing,
we were asked by the editor of this prestigious journal to write an article
commenting on the other work presented in the issue – wonderful research done
at Emory University on the use of gestures by chimpanzees. We were particularly
thrilled when a picture of one of our own "Baby Signers" was used for
the cover of the issue.
Susan Goodwyn and Linda Acredolo (1998). Encouraging symbolic
gestures: Effects on the relationship between gesture and speech. In J. Iverson
& S. Goldin-Meadows (Eds.) The nature and functions of gesture in
children’s communication (pp. 61-73). San Francisco: Jossey-Bass.
This invited chapter provided an opportunity for us to summarize our program of
research on symbolic gesturing, from the earliest work with Kate to the results
of our NIH-sponsored longitudinal study of the impact of gesturing on verbal
development.
Linda Acredolo, Susan Goodwyn, Karen Horobin, and Yvonne Emmons
(1999). The signs and sounds of early language development. In L. Balter &
C. Tamis-LeMonda (Eds.), Child Psychology: A Handbook of Contemporary Issues
(pp. 116 - 139). New York: Psychology Press.
The editors of this volume asked us to do more than simply summarize our
research findings. We were delighted to accept the challenge. Our goal in the
chapter was to show how the results of our studies of symbolic gesturing shed
light on important and still unresolved questions in language development: Why
does comprehension of language generally precede production? Why is vocabulary
growth so slow in the months following the first word? What accounts for the
frequently observed phenomenon called the "vocabulary spurt?" What
developments underlie the beginning of the "two word" stage? In the
final section of the chapter we challenge researchers to begin using symbolic
gesturing as a tool to explore other important developmental issues, issues that
have traditionally had to await the onset of verbal language (e.g., longterm
memory for events, concept development, abstract thinking, emotional knowledge).
As an added bonus the chapter includes nearly a dozen vignettes drawn from our
data and chosen to illustrate the Baby Signs® creativity we've seen
babies use over and over.
Goodwyn, S.W.,Acredolo, L.P., & Brown, C. (2000). Impact of
symbolic gesturing on early language development. Journal of Nonverbal Behavior.
24,81-103.
This is the article in which we present the most important findings from our NIH-sponsored
longitudinal study of the impact on verbal development of purposefully
encouraging infants to use symbolic gestures. Standardized tests of both
receptive and expressive language development had been administered at 11, 15,
19, 24, 30, and 36 months to both an experimental group of babies ("Baby
Signers") and two control groups. Results demonstrated a clear advantage
for the Baby Signs® babies, thereby laying to rest the most
frequently voiced concern of parents – that using the Baby Signs®
Program might hamper learning to talk. In fact, the good news is that Baby Signs®
communication actually facilitates verbal language development.
Acredolo, L. P., & Goodwyn, S.W. (July 2000). The long-term
impact of symbolic gesturing during infancy on IQ at age 8. Paper presented at
the meetings of the International Society for Infant Studies, Brighton, UK.
The WISC-III was administered to subjects from our NIH-sponsored longitudinal
study during the summer following completion of second grade. Much to our
surprise and delight, the results indicated a significant 12 point advantage for
the children who had been encouraged to use the Baby Signs® Program
during their second year of life (Mean IQ = 114) over the children who had been
in the Non-Intervention Control Group (Mean IQ= 102). The advantage held for
both the Verbal and Performance Sub-scales of the WISC-III.
Brie Moore, Linda Acredolo, & Susan Goodwyn (April 2001).
Symbolic gesturing and joint attention: Partners in facilitating verbal
development. Paper presented at the Biennial Meetings of the Society for
Research in Child Development.
Using video data collected in our federally funded, longitudinal study, we
looked to see whether the Baby Signs® experience stimulates
development of the ability to actively direct an adult's attention to something
in which the baby is interested. Called, "joint attention," this
ability is known to be an important contributor to learning to talk. Much to our
delight, the Baby Signs® babies were indeed found to engage in more
joint attention episodes with their mothers than did non- Baby Signs®
babies during laboratory play sessions at 19 and 24 months. Moreover, the effect
held independently of linguistic skill, indicating that the Baby Signs®
experience itself was a unique contributor to the joint attention scores. These
data are important because they help explain why Baby Signs® babies
tend to learn to talk earlier than non-Baby Signs® babies. The study
may also help explain why the Baby Signs® experience has been found
to have a positive effect on IQ at age 8.
