Language Effects in Noise-Induced Word Misperceptions

Speech misperceptions provide a window into the processes underlying spoken language comprehension. One approach shown to catalyse robust misperceptions is to embed words in noise. However, the use of masking noise makes it difficult to measure the relative contributions of low-level auditory processing and higher-level factors which involve the deployment of linguistic experience. The current study addresses this confound by comparing noise-induced misperceptions in two languages, Spanish and English, which display marked phonological differences in properties such as consonant-vowel ratio, rhythm and syllable structure. An analysis of over 5000 word-level misperceptions generated using a common experimental framework in the two languages reveals some striking similarities: the proportion of confusions generated by three distinct types of masker are almost identical for the two languages, as are the proportions of phonemic and syllabic insertions, deletions and substitutions. The biggest difference is seen for babble noise, which tends to induce relatively complex confusions in English and simpler confusions in Spanish. We speculate that the inflectional morphology of Spanish lends itself to more easily recruit single elements from a babble masker into valid word hypotheses.