Visual cues help face-to-face communication
A recent study of sign language and spoken language that is seen but not heard has highlighted the importance of visual cues in face-to-face communication.
PhD student Jordan Fenlon was supported by Deafness Research UK to carry out the research with Professor Bencie Woll at the Deafness Cognition and Language (DCAL) Research Centre at University College London.
When listening to speech people use the speaker's prosody – changes in pitch, pauses and the length of sounds – to break the speech into chunks that can be more easily understood. There is also a wide range of visual cues available that are used to complement auditory cues. The study explored these cues and also the visual cues that mark the boundaries of sentences in sign language and whether different groups of people could use them for sentence segmentation.
An initial analysis of British Sign Language (BSL) found that cues like head nods, torso leaning, blinks and facial expression mark sentence boundaries in similar ways to those previously found for other sign languages and for spoken languages.
Signers with first-language BSL, American or Swedish sign language, and a group of English-speaking hearing non-signers were asked to watch narratives signed in the three languages. Their task was to press a button when they saw a visual ‘full-stop’ at the end of a sentence. The hearing English speakers and BSL signers also watched narratives in English with the sound turned off, and were asked to do the same task.
All groups were able to able to identify the sentence boundaries at levels significantly above chance. This was true in their own language and in a sign language they did not know, even though the context and grammar of the narrative in the unfamiliar language could not be understood. Similarly, they were able to make such judgements in silent English. In addition, signers and non-signers could tell the difference between the full-stops and the boundaries that occurred within sentences.
The results show that visual cues alone are an important aid to understanding face-to-face communication. The next steps will be to investigate how visual prosodic cues are used to improve comprehension in speech-reading and in understanding sign language.
Professor Woll said, “We often don't realise that non-verbal visual cues play an important part in communication in both spoken language and sign language. By understanding the role of vision in language we can begin to develop better approaches to improving the communication of deaf and hard of hearing people”.
