The use of short-term memory in the discrimination of visually-influenced CV-syllables

抄録

The discrimination of three kinds of CV syllables, consisting of a stop consonant and a vowel (/ba/, /da/, and /ga/), was experimentally investigated using an AX-discrimination paradigm under auditory-alone, visual-alone, and audiovisual presentation conditions. The role of shortterm memories was examined by evaluating the strength of two psychological effects-the stimulus order effect (SOE) and the effect of temporal interval of stimulus onset asynchrony (SOA). For the conditions other than the visual-alone condition, 14 subjects were instructed to compare the timbres of the paired stimuli. It was investigated how auditory and phonetic memories are made use of in the discrimination of audiovisual stimuli and their temporal decay characteristics. The SOA was either two or four seconds. The stimuli were audiovisually congruent and incongruent CV-syllables. The effect of SOA was found and weak evidence for the SOE was obtained. The results are discussed with regard to the role of auditory and phonetic memories. The results can be interpreted that the auditory memory of the non-fused syllable had the characteristics similar to that of the prototype, while the auditory memory of the fused syllable had the characteristics similar to the midway stimulus on the stimulus continuum.