Efficacy and social validity of intervention using speech generating device and tactile symbols to develop communication and language in a child with visual impairment and additional disability

Visual impairment (VI) can significantly hinder language development in children. While VI alone may not drastically alter the trajectory of language acquisition, the presence of additional disabilities can pose significant challenges. Despite these difficulties, augmentative and alternative communication (AAC) strategies, such as speech-generating devices (SGDs) and tactile symbols, have shown promise in supporting communication and language development in such children. This study investigated the efficacy of a targeted AAC intervention utilizing an SGD and individualized tactile symbols to enhance communication functions, receptive and expressive language skills in a non-verbal child with VI and additional disabilities. Additionally, the study explored the caregiver's satisfaction with the intervention. A longitudinal case study method was employed to meet the study purpose. A baseline assessment of communication and language skills was done prior to intervention. Intervention using SGD and tactile symbols were carried out in three phases and outcomes were measured once during the intervention phase and once again after providing intervention. The intervention, conducted over 40 sessions, yielded positive results, demonstrating a significant impact on the child's communication and language development. Notably, the child also developed meaningful speech during the intervention period. The primary caregiver rated the outcomes of the intervention as highly beneficial to the child. The study concludes that a well-structured intervention, incorporating both technological and tactile modalities, can substantially enhance the speech, language, and communication skills of children with VI and additional disabilities.