Polar Questions (PQs) are an essential component of human communication and are present in most languages. Although their morphosyntactic, prosodic, and semantic characteristics in spoken languages have been extensively studied, significant gaps in knowledge remain: (a) what visual cues mark PQs in spoken languages and how these markers influence their usage; (b) what forms and conditions of use (non-)canonical PQs exhibit in sign languages; (c) what semantic contributions are made by visual cues such as head and eyebrow movements, nose wrinkling, or shoulder raises. Additionally, a deeper understanding of the status of form-meaning mappings in visual cues is necessary—are they arbitrary, or are they motivated by iconicity or biological factors?

Our project addresses these gaps through experimental and corpus-linguistic studies of PQs in German Sign Language (Deutsche Gebärdensprache, DGS) and German. The research questions guiding our study are:

(1) Which visual cues are employed in DGS/German across different types of PQs (e.g., positive/negative PQs, with interrogative versus declarative syntax, particles, question tags)?

(2) How do visual cues influence the contextual usage of various PQ types in DGS/German (considering parameters such as speaker assumptions and preferences, as well as contextual evidence for or against a proposition)?

(3) What semantic contributions do visual cues make in both language modalities (e.g., indicating speaker assumptions/preferences, expressing surprise based on contextual evidence)?

(4) How similar or different is the use of visual cues between DGS and German, and what does this reveal about the status of some visual cues as biological reflexes of mental states (e.g., surprise, doubt)?

These questions are investigated through corpus-linguistic and experimental methods.

Work Package 1 (WP1) focuses on DGS: it aims to identify the various forms of PQs in the DGS corpus (WP1a), and to examine contextual factors affecting their well-formedness via production studies (WP1b) and felicity judgment experiments (WP1c).

Work Package 2 (WP2) pertains to German: it seeks to identify potential visual markers across different PQ types in audiovisual corpora (WP2a) and involves eliciting productions of these various PQ types in different contexts (considering factors such as speaker assumptions, preferences, and contextual evidence) through speaker experiments (WP2b).

Based on the empirical and analytical findings from WP1 and WP2, WP3 develops a formalized theory of the semantic contribution of visual cues to PQs in DGS and German. Additionally, we will discuss the broader theoretical issue of whether the form-meaning mapping in visual cues is arbitrary or motivated by biological factors.

Our project concentrates on two central modalities of visual communication—sign languages and co-speech gestures—and thus aligns well with the research scope of ViCom. We contribute to ViCom’s goal of advancing linguistic theory by developing a formally precise, multimodal model of the semantics of PQs.