The Efficiency of Information Transmission of Sign and Spoken Language

The study compares sign and oral language in terms of information transmission efficiency. The sample consisted of 36 hearing people with no knowledge of sign language and 36 deaf people reasonably fluent in sign language. (The deaf participants' level of hearing loss ranged from severe to profound.) Oral and sign language comprehension was assessed by means of texts at three different difficulty levels. After being exposed to the texts, the study participants had to tell what they had understood about them, answer a set of related questions, and offer a title for each text. When the hearing group's comprehension of oral versions of the texts was compared to the deaf group's comprehension of signed versions, the deaf group showed better comprehension of the explicit content of the texts but added more invented content and made more errors.