Learning from Documentaries in Signing Deaf Individuals: Subtitles in Written Sign Language Improve Comprehension.

Deaf individuals with a profound hearing loss have a poor comprehension of both vocal and written language (e.g., Van Hoogmoed et al., 2011); several studies reveal the utility for them of visual supports like multimedia materials in didactic contexts (e.g., Passig & Eden, 2003). We assumed that text/discourse comprehension relies on the construction of a mental model of its contents, and that the information conveyed through videos, represented in a non-discrete format, is easily included in the mental model of the text/discourse because mental models too are non-discrete representations (Vendrame et al., 2010). Our experimental results confirmed that signing deaf individuals, as compared to hearing individuals, have comparable performance when the information to be learnt are presented through videos. Also, we found that a transposition of the Italian Sign Language (L.I.S.) to its written counterpart enhances signing deaf individuals’ comprehension and learning from text, as it activates visual thought schemata similar to those activated by the sign language itself (Vendrame et al., submitted). The focus of the present study was on signing deaf individuals’ comprehension and learning from subtitled documentaries. Documentaries are frequently accompanied by subtitles which are not fully comprehensible to deaf individuals because they are provided in written verbal language. We predicted that signing deaf individuals perform better in comprehending and learning from documentaries subtitled in written L.I.S as compared to those subtitled in written Italian. We tested our prediction with an experiment on signing deaf individuals using a free recall task. The participants were invited to carefully watch two documentaries, one subtitled in Italian, the other in written L.I.S. Then they were invited to recall as much information as they could. The result of our experiment on twelve signing deaf individuals with a prelingually profound hearing deficit (>90 dB hearing loss) confirmed our prediction. In line with our previous studies, the results of our experiment confirmed that signing deaf individuals benefited from the written L.I.S. subtitled version of the documentaries. Our results have relevant implications; as signing deaf people have difficulties in comprehending the written versions of oral languages, their opportunities to learn from written texts – and therefore to benefit from school and university education – are heavily restricted. Providing them access to comprehensible written information reflecting their sign language would be an important advance. Further studies might investigate the benefit of written sign language early in the development of signing deaf children.