The contribution of head gesture prominence in the multimodal marking of information structure in French and Italian

Previous research has shown that gestures frequently co-occur with prosody in marking information structure (IS) (e.g., Im & Baumann, 2020; Rohrer, 2022). Two recent studies (Baills & Baumann, 2025; Baills, de Paolis, & Baumann, 2025) found that expressions referring to new, inferable, and contrastive elements , are more often accompanied by a pitch accent alone or by a pitch accent combined with a head gesture, compared to expressions referring to given elements in French narrative speech. These studies also revealed that common non-canonical syntactic constructions—such as fronting, dislocation, and presentational constructions—also tend to trigger increased multimodal marking, including head gestures, even with given information. However, while the presence of head gestures appears relevant, the specific type of gesture (e.g., nod, turn, protrusion) does not seem to play a significant role, leaving open the question of which components of head gestures contribute to signalling discourse-level distinctions.Using audiovisual narrative data from 10 French and 10 Italian speakers, this study investigates how the perceived prominence and duration of head gestures contribute to the multimodal marking of information status and contrastive focus in spoken discourse.Discourse-level information is annotated along several dimensions: information structure following a simplified version of the RefLex system (Riester & Baumann, 2017), syntactic constructions based on the taxonomy by Brunetti et al. (2011), and prosodic cues following ToBI conventions (Delais-Roussarie et al., 2015; Gili Fivela et al., 2015). Head gestures' phases and perceived prominence are annotated using the M3D scheme (Rohrer et al., 2025). Additionally, gesture stroke duration is automatically extracted from the annotations. Relative prominence refers to the degree to which a gesture stands out visually in its discourse context, as judged by human observers. Since prominence is a perceptual and context-dependent phenomenon, it cannot be fully captured by gesture type alone. In addition to perceptual annotation, we measure gesture stroke duration as an objective phonetic correlate, motivated by the observation that more prominent gestures often display longer or more effortful strokes.The study aims to clarify how visual salience is constructed and to uncover potential cross-linguistic patterns in the timing, frequency, and integration of prominent head gestures within prosodic structure. These findings will help specify which visual features of head gestures contribute to meaning construction and offer methodological insights for gesture annotation in multimodal linguistic research.