Sentence-level rhythmic regularity and accentual-group phrasing increase linguistic resemblance between Spanish-speaking interlocutors

In two empirical studies, we examined the impact of speech rhythm on linguistic accommodation during conversational interactions. We compared dyadic interactions between Spanish speakers using regular and irregular rhythmic sentences structured by accentual feet (inter-stress intervals) and accentual groups. Acoustic-prosodic features (fundamental frequency, speech rate, response times) and resemblance measures (Euclidean distances) were analyzed. Additionally, independent listeners rated rhythmic resemblance between dyads. Linear mixed-effects models revealed greater resemblance in rhythm and F0 range, lower F0 mean, and narrower F0 range in interactions involving regular rhythmic sentences arranged in accentual groups. No differences were observed in response times or convergence measures between interlocutors across conditions. Some of our findings support the notion that rhythmic accommodation operates through a multilevel non-conscious mechanism, similar to that proposed by the interactive alignment model.