The Development of the Ability to Semantically Integrate Information in Speech and Iconic Gesture in Comprehension.

We examined whether children's ability to integrate speech and gesture follows the pattern of a broader developmental shift between 3- and 5-year-old children (Ramscar & Gitcho, 2007) regarding the ability to process two pieces of information simultaneously. In Experiment 1, 3-year-olds, 5-year-olds, and adults were presented with either an iconic gesture or a spoken sentence or a combination of the two on a computer screen, and they were instructed to select a photograph that best matched the message. The 3-year-olds did not integrate information in speech and gesture, but 5-year-olds and adults did. In Experiment 2, 3-year-old children were presented with the same speech and gesture as in Experiment 1 that were produced live by an experimenter. When presented live, 3-year-olds could integrate speech and gesture. We concluded that development of the integration ability is a part of the broader developmental shift; however, live-presentation facilitates the nascent integration ability in 3-year-olds.