Children with Down syndrome (DS) have language development particularities that have negative effects in the communication capacity. By this way, Augmentative and Alternative Communication (AAC) is indicated to this population. The aim of this study was to verify the AAC impact in the lexical gain of children with DS.

Five children with DS, with the same cognitive level, participated in this study. Longitudinal follow-up of twelve months of speech-language therapy with AAC use was undertaken. A lexical evaluation was done at the beginning and the end of this follow-up. Correct responses in the lexical evaluation were increased, but not necessarily in the spoken modality. The comparisons showed significant results in use of substitutions processes, and to no-answers.

Inclusion Criteria:

• genetic diagnosis of Down syndrome
• be at the preoperational period
• good health conditions
• expressive language impairment (communication by vocal and gestures, predominantly)

Exclusion Criteria:

• presence of major malformations
• presence of another genetic syndrome
• severe neonatal asphyxia, hearing impairment or visual