An Analysis of the Visual and Auditory Aspects of Sound Blending Including Central Auditory Integration as Measured on the Maid. Final Report.

Analyzed was the performance of 30 children with normal reading and speech skills on various blending tasks. There were three groups of ten Ss each with each group receiving one of three modes of presentation: auditory, visual, or auditory visual. The stimuli consisted of 150 consonant-vowel (CV), vowel-consonant (VC), and consonant-vowel-consonant (CVC) syllables. CVCs were all familiar words; CVs were all nonsense words and VCs were either real or nonsense words. In the auditory mode, sound segments representing the phonemes of the syllables were spoken at stimulus onset asynchrony (SOA) times of 500, 750, and 1000 milli-second; in the visual mode, letters corresponding to the phonemes of the syllables were projected serially at the same SOA times; and in the audio-visual mode, letters and sound segments were presented concurrently. Ss responded by speaking the syllable which had been presented in segments. Results indicated a significant effect for mode of presentation, with auditory-visual yielding the most and auditory the fewest correct responses. Syllable type also had a significant effect; CVCs presented in two segments (C-VC or CV-C) were easier than C-V, V-C, or C-V-C. Meaning and rate of presentation did not have a clear effect on performance. (Author/SBH)