English, Spanish, and bilingual speakers' performance on a nonsense syllable test (NST) of speech sound discrimination.

Abstract

This study investigated the ability of a 25-item open-set CVCV Nonsense Syllable Test (NST; Edgerton & Danhauer, 1979) to assess English, Spanish, and bilingual native speakers' speech sound discrimination skills (i.e., both the subjects and the NST were evaluated). The NST was presented at five sensation levels (SLs) between 25 and 65 dB to 29 normally hearing individuals from three native language backgrounds: monolingual English speakers, bilingual Spanish-English speakers having equal experience in each language, and Spanish speakers having little exposure to English. Articulation functions were plotted for each group and compared across SLs, groups, and scoring methods. Results indicated that the phoneme scoring method best described the responses, and all groups' scores improved with increases in SL until they reached a plateau at 45 dB SL. The bilingual group performed similarly to the English speakers; but, as expected, the Spanish group scored significantly poorer than the other two groups. Thus, while the NST may not be highly useful for Spanish speakers, it can help describe the speech sound discrimination abilities of bilingual (Spanish-English) speakers.