Here are a few links to research sites that has been done on teaching infants sign language:
"Signs of Intelligent Life"
by Margaret Jaworski, Family Circle, October 3, 2000, p. 14.
"Sign, Baby, Sign!"
by Kristin Snoddon, World Federation of Deaf News, May 2000, pp. 16-17.
Acredolo, L.P., Goodwyn, S.W., Brown, Catherine,
Impact of Symbolic Gesturing on Early Language Development - Journal of Nonverbal Behavior, 24, 81-103.
Acredolo, L. P., & Goodwyn, S.W. (July 2000).
The Long-term Impact of Symbolic Gesturing During Infancy on IQ at age 8.
Daniels, M. (1994). The Effects of Sign Language on Hearing Children's Language Development.
Communication Education, October, v43 n4, p291 (8).
Daniels, M. (1996). Seeing Language: The Effect Over Time of Sign Language on Vocabulary Development in Early Childhood
Education. Child Study Journal, 26, 193-208.
Feltzer, Laura, MBR Reading Program:
How Signing Helps Hearing Children Learn to Read - Research Summary
Donovan, Claire S-LP, (1998) Teaching Sign Language, Disability Solutions, Volume 2, Issue 5, January/February 1998.
Square PA., (1994) Treatment Approaches For Developmental Apraxia Of Speech.
Clinical Communication Disorders, Sept; 4(3): 151-61.
We look forward to hearing from you.
Hafer, Jan C, and Robert M. Wilson. Signing for Reading Success.