Participants Conform to Humans but Not to Humanoid Robots in an English Past Tense Formation Task

In this article, we discuss the results of an experiment designed to test the boundaries of linguistic imitation in a group setting. While most prior work has focused on convergence in either sound structure or syntax, we investigate whether speakers’ choices in verb morphology are influenced by others. The experiment uses an Asch-type peer pressure methodology. Participants give responses to target stimuli in a verbal and a visual task in a group of human peers, a group of robots, or alone. These results demonstrate that morphological conformity occurs, but that it is socially constrained—it happens with human peers but not with robot peers. This supports a view of linguistic convergence as a deeply social process. The level of linguistic conformity displayed by individuals is related to their degree of conformity in nonlinguistic tasks, suggesting that there are individual propensities toward peer imitation that transcend modalities