Poster #: 123
Topic: Speech and language (incl. deficits)
Friday, Sep 11, 2015
Audiovisual speech perception of homophones using mismatch negativity
All India Institute of Speech and Hearing, Manasagangothri, Mysore, India
Speech perception is a multimodal process. It combines both auditory and visual sense for integration of auditory information. Visual cues can supplement the missing auditory information. However, if the auditory sounds are same with only difference in visual characteristics of speech, it might either facilitate greater or lesser degrees of integration depending on the pre-attentive cognitive skills. Hence, the present study investigated the effect of visual contribution of homophones to its auditory perception using mismatch negativity in non-native English speaker. The study included 30 ears in the age range of 18 to 40 years. The recorded homophones were continuously presented auditorily in an oddball paradigm, while visual written words were presented in synchronization with the auditory stimuli. The experiment was done 03 conditions: only in auditory mode, only in visual mode and in both audiovisual mode. The results indicated the better elicitation and early latency of MMN in audio visual mode indicating the neural activators of visual and auditory cortex and the pre-attentive cognitive skills. However, MMN was not elicited in auditory only mode as there exist no difference in the characteristic of the sound. This indicates that the visual mode could add to the understanding ability in concordance with the auditory perception. Even with no difference in the perception of auditory stimulus, the neural activators of visual cortex could stimulate the area of phonological processing and also tapping the pre-attentive cognitive skills for understanding.