Trust is an important aspect of daily-life communication. We decide whether to trust someone based on just a face or a voice. Trust is part of credibility and is invariably connected to expertise....Show moreTrust is an important aspect of daily-life communication. We decide whether to trust someone based on just a face or a voice. Trust is part of credibility and is invariably connected to expertise. Previous research on credibility, expertise and trustworthiness has shown the impact of disfluencies on all three aspects. However, it has often focused only on native speech, and never used the duration of empty pauses as a fluency measure. The current study investigated the effect of empty pause manipulations in both native and non-native speech on perceived competency-based trustworthiness in two scenarios, differing in the level of expertise. Recordings of a native and a non-native speaker were manipulated phonetically, which resulted in two conditions: long empty pauses (LongPauses) and no empty pauses (NoPauses). The perceived competency-based trustworthiness of the speakers was measured using a 5-point likert-scale, based on McCroskey’s (1966) authoritativeness scale. Results indicated a significant effect for scenario and an interaction effect between scenario and nativeness. Post-hoc t-tests showed that the native speaker was perceived as significantly less trustworthy than the non-native speaker in the non-expert scenario. Second post-hoc t-tests showed that the native speaker was perceived as significantly more competency-based trustworthy in the expert scenario, than in the non-expert scenario. This same effect was not found for the non-native speaker. Follow-up questions showed that listeners in the native group indicated that the implied expertise in the scenarios did affect their judgements of the speaker, while the listeners in the non-native group indicated it did not.Show less