Sensitivity to temporal synchrony in audiovisual speech in early infancy: Current issues and future avenues.

Audiovisual speech integration during infancy is crucial for socio-cognitive development. A keyperceptual cue infants use to achieve this is temporal synchrony detection. Although the currentdevelopmental literature on this ability is rich, unsolved disagreements obscure the interpretationof findings. Here, we propose conceptual and methodological issues that may have contributed toa still unclear picture of the developmental trajectory of sensitivity to temporal synchrony,particularly when studied in audiovisual fluent speech. We discuss several sources of confusion,including a lack of terminological precision, heterogeneity in the experimental manipulationsconducted, and in the paradigms and stimuli used. We propose an approach that clarifies thedefinition and operationalization of sensitivity to temporal synchrony and explores its developmentalcourse, emphasizing the role of infants’ linguistic experiences. Ultimately, we expect thatour analytical review will contribute to the field by aligning theoretical constructs, proposingmore fine-grained designs, and using stimuli closer to infants’ experiences.