Gestural communication learning in mentally retarded adults with Down's syndrome

Ten mentally retarded adults with Down's Syndrome were assigned to American Indian Gestural Code (Amer-Ind) and American Sign Language (ASL) teaching groups to compare sign comprehension, imitation, and retrieval learning in relation to system characteristics (iconicity, motoric complexity of signs) and subject specific factors (language and motoric ability). Twenty lexica l items, significantly different in iconicity and motor difficulty for the two gestural systems, were taught to the subjects during 20 thirty-minute s essions. Statistical analyses revealed significant differences in individua l subject performance at five session measurement intervals but no signific ant differences between the two groups. Subject factors rather than differe nces in sign system characteristics appeared to be the best predictors of l anguage/gestural code learning for the mentally retarded adults.