The role of fundamental frequency in phonetic accommodation

Previous research has argued that fundamental frequency is a critical component of phonetic accommodation. We tested this hypothesis in an auditory naming task with two conditions. Participants in an unfiltered condition completed an auditory naming task with a single male model talker. A second group of participants was assigned to a filtered condition where the same stimuli had been high-pass filtered at 300 Hz, thereby eliminating the fundamental frequency. Acoustic analysis of f0 revealed that participants assigned to the unfiltered condition imitated the pitch of the model talker more than those assigned to the filtered condition. Although accommodation was statistically significant, the effect was small, so we followed with a perception study to examine listeners' abilities to detect differences in accommodation across conditions. Shadowed tokens from participants in the unfiltered condition were indeed judged by listeners to be more similar to the model talker's productions that those from participants in the filtered condition. However, acoustic measurements and listener judgments of accommodation were not significantly correlated, enforcing the intuitive concept that accommodation and listeners' judgments of similarity are holistic and do not hone in on singular features in the acoustic signal.