Syntactic chameleons: Are there individual differences in syntactic mimicry and its possible prosocial effects?

This study investigated whether syntactic mimicry leads to prosocial effects and whether any such effects are modulated by personality traits. Participants and a confederate of the experimenters took turns describing simple scenes. Target scenes could be described using either a prepositional object or a double object dative structure and we tested whether the participants mimicked the structure used by the confederate (Experiments 1A and 2A), whether mimicry of the participant's sentence structure (Experiments 1B and 2B) made the participant act in a more prosocial manner, and whether any such effects vary with Big Five traits. Participants displayed significant syntactic mimicry, which was additionally negatively related to levels of Extraversion. Syntactic mimicry did not lead to more prosocial behavior, as gauged by the time spent on an extra task (Experiment 1B). This conclusion was confirmed in Experiment 2B, which used a slight adaptation of the task that prevented a ceiling effect. However, a positive relation between prosocial behavior and levels of Conscientiousness was observed in the mimicry condition, which appeared to invert in the non-mimicry condition. We discuss several potential reasons for the absence of prosocial effects of syntactic mimicry and provide suggestions for future research.