Eye-movement Comparison in Reading in Deaf and Hearing Russian Sign Language Speakers

This research work focuses on the study of reading in deaf and hearing Russian sign language (RSL) native speakers. Clarifying both groups’ reading features may be of crucial importance for improving educational programs for people with hearing disorders. The deaf are the only readers not relying on phonological codes. Presumably, the phonological deficit affects the deaf’s language development, and they read worse than hearing people (Bélanger, 2015). At the same time, the deaf have an advantage in visual processing that helps them read: they have a wider visual perception field and extract more characters to the right from the current fixation than hearing readers (Bélanger, Slattery, 2012). Visual attention studies also confirm that the deaf have a wider visual perception field than the hearing (Bavelier, 2006). We compared eye movements while reading in partially hearing (N=13, using both speech and sign language) and deaf (N=13, only using sign language) RSL speakers. They were to read 144 sentences of Russian Sentence Corpus (Laurinavichyute, 2019). We hypothesized that reading would be more impaired in the deaf and tested whether enhanced peripheral vision helps people with partial hearing loss to the same extent as it helps the deaf. A study of visual attention was also conducted to investigate participants’ ability to search objects in limited and unlimited perception field modes. The results demonstrated that both groups have comparable reading skills: similar fixations durations, skipping rates, number of fixations per word, landing positions of the saccade, word and sentence processing speeds. However, we found an indication that deaf individuals might perform worse in some aspects of reading. Comprehension question responses showed that the deaf understand or/and remember what they read worse than the hearing do. Moreover, short words (conjunctions, particles, prepositions) facilitate reading for the deaf significantly more than for the hearing. Both the deaf and the hearing demonstrated that they can effectively extract parafoveal information while reading. Deaf people process long words more effectively than the hearing: they are better in extracting the information from long words with a single fixation. As for the hearing, increasing frequency of the next word helps them to accelerate in reading and rereading of the current word and reduce the number of fixations on it. Visual attention experiment reveals no significant difference between deaf and hearing participants’ reaction times in finding stimuli on the screen. Thus, we found, first, that both deaf and hearing RSL native speakers have mostly comparable reading skills. Second, that both groups can effectively extract information on the periphery while reading sentences.