Influence of voice properties on vowel perception depends on speaker context.

Different speakers produce the same intended vowel with very different physical properties. Fundamental frequency (F 0 ) and formant frequencies (F F ), the two main parameters that discriminate between voices, also influence vowel perception. While it has been shown that listeners comprehend speech more accurately if they are familiar with a talker's voice, it is still unclear how such prior information is used when decoding the speech stream. In three online experiments, we examined the influence of speaker context via F 0 and F F shifts on the perception of /o/-/u/ vowel contrasts. Participants perceived vowels from an /o/-/u/ continuum shifted toward /u/ when F 0 was lowered or F F increased relative to the original speaker's voice and vice versa. This shift was reduced when the speakers were presented in a block-wise context compared to random order. Conversely, the original base voice was perceived to be shifted toward /u/ when presented in the context of a low F 0 or high F F speaker, compared to a shift toward /o/ with high F 0 or low F F speaker context. These findings demonstrate that that F 0 and F F jointly influence vowel perception in speaker context.