Adults mark the communicative relevance of their gestures more for children than for other adults

According to relevance theory, communication relies on speakers’ ability tosignal relevant information, which addressees use to infer meaning effi-ciently. Most research within the relevance theoretic framework has exam-ined how relevance is marked in speech, treating it as the primary channel forsignaling informative content. Yet, little is known about whether, how, and inwhat contexts speakers highlight information in co-speech gestures. Here,we investigate how speakers use ostensive cues—specifically, visual andverbal deixis (e.g. gaze toward a gesture, demonstratives like “this,” “that,”or “here”)—to highlight the communicative relevance of iconic gestures inchild- versus adult-directed communication and whether addressees showsensitivity to these cues. Sixteen Italian adults explained the rules of twologic puzzles to a child and another adult. Results show that speakers high-light more gestures for children than for adults, primarily by using visualdeixis. Furthermore, addressees of both age groups, adults and children,were more likely to shift their gaze to highlighted than to non-highlightedgestures. These findings demonstrate that speakers dynamically adapt multi-modal cues to highlight iconic gestures for addressees, providing empiricalsupport for extending relevance theory to a multimodal view of language