Perceiving audiovisual synchrony: A quantitative synthesis of simultaneity and temporal order judgments from 185 studies

Despite decades of research, there is still no consensus on when audiovisual events are perceived as simultaneous. Estimates vary widely across studies-often contradicting one another-hindering the field's ability to draw general conclusions. Two widely used paradigms-simultaneity judgments and temporal order judgments-differ not only in task demands but also in reported outcomes, fuelling debate about their comparability and validity. Here we present a large-scale, quantitative synthesis of audiovisual timing perception, drawing on findings from 185 published experiments. To support meaningful comparison across studies, we adopt a harmonized analytic framework to distil key temporal sensitivity measures and introduce a generalizable criterion for assessing the quality of psychometric sampling. This synthesis reveals that many reported differences in audiovisual synchrony perception arise not from genuine perceptual differences, but from methodological heterogeneity-particularly in the sampling of temporal lags and whether experiments were lab-based or conducted online. These artefacts have complicated theory development and undermined reproducibility. We propose concrete recommendations for task design, analysis, and interpretation, and offer an open-access resource to support future research and modelling efforts in sensory timing.