RESUMEN
Signing is a commonly used intervention technique for children with cognitive impairments who have expressive language delays. Novel word learning in three conditions (signed only, spoken only, signed and spoken combined) was compared for children with Down syndrome (2;1 to 5;2) and mental-age matched control children (1;4 to 2;6). Spontaneous imitations and responses to production and comprehension probes were examined after 5, 10, and 15 word exposures. No group differences in frequency of imitations or productions were obtained. The frequency of imitations was highest in the combined condition. Probed productions were infrequent, although novel words were produced most often in spoken and combined conditions. For both imitated and probed productions in the combined condition, the spoken portion was almost exclusively produced. Across conditions, children with Down syndrome comprehended fewer words than did control children. The evidence for and explanations of the facilitative effect of signs and the advantage of dual-method presentation are discussed.