Do Voice Acoustic Parameters Differ Between Bilingual English-Spanish Speakers and Monolingual English Speakers During English Productions?

Background. In addition to language differences in fundamental frequency between bilinguals and monolinguals, studies have also included other acoustic parameters to analyze differences in voice production associated with the language spoken. Aim. To identify differences in voice acoustic parameters during English productions between monolingual and bilingual English speakers. Method. Exploratory cross-sectional study with two groups of subjects: monolingual English speakers (n = 40), and bilingual English-Spanish speakers (n = 13). Participants filled out a questionnaire and recorded one reading in English (second sentence of Rainbow passage "The rainbow is a division of white light into many beautiful colors") under a "virtual-simulated" acoustic condition of No Noise and Medium Reverberation Time (0.8 seconds). Result. Analysis by gender shows that monolingual speakers had higher fundamental frequency mode, and lower standard deviation of fundamental frequency compared to bilingual English-Spanish speakers. Bilingual male speakers had higher jitter and harmonics-to-noise ratio than monolingual speakers. On the contrary, female bilingual speakers had lower jitter and shimmer than monolingual speakers. Conclusions. Speaking a second language may influence voice acoustic parameters, and therefore, should be considered when comparing acoustic speech metrics.