Symbolic gesture versus word: is there a modality advantage for onset of symbol use?

Researchers have hypothesized in the past that children learning sign languages develop signs at an earlier age than is typically expected for vocal words. This assumption, however, has recently been questioned on the grounds that researchers have not always guaranteed that words and gestures are being used in a comparable fashion. The present study was designed to shed light on this controversy by comparing the onset of symbolic use of signs and words in a group of 22 hearing children exposed to symbolic gestures from 11 months onward. Bimonthly interviews emphasizing contexts of use of gestures and vocal words indicated a smaller modality difference than early research had predicted, thus providing support for the hypothesis that strides in cognitive abilities such as memory, categorization, and symbolization underlie this milestone in both modalities. At the same time, however, the data also indicated that the small difference in onset time was reliable, thus providing support for the notion that the gestural modality is, in fact, easier for many infants to master once the requisite cognitive skills are in place.