Viewpoint on Developmental Aspects of Multisensory Integration Across the Lifespan.

In this viewpoint article, Andy Bremner, Patrick Bruns and Fiona Newell provide an integrated perspective on how multisensory processing develops and changes across the lifespan. From their complementary backgrounds in infant development, crossmodal learning, and visual cognition, they reflect on the scientific influences that shaped their own research trajectories and discuss major conceptual and methodological advances in the field. These include emerging brain-imaging techniques that offer new insights into the foetal and postnatal development of multisensory processes, computational approaches such as Bayesian causal inference models, and studies of sensory deprivation and restoration that illuminate the plasticity of multisensory systems. The authors outline ongoing controversies, such as the interpretation of infant behavioural measures, the developmental timing of multisensory integration, and the causal relationship between sensory and cognitive ageing. They also discuss the expanding role of open science, for example, data sharing, preregistration, and methodological transparency, while noting practical and conceptual challenges for a field that relies on complex, resource-intensive developmental research. They emphasise the need for methodological harmonisation, cross-lab replication, and ecologically valid research approaches that capture multisensory processing in real-world environments. Looking ahead, they anticipate progress driven by AI-assisted data analysis, advances in infant and lifespan brain imaging, and increased attention to interindividual differences in multisensory development. Finally, they encourage early-career researchers to embrace interdisciplinary collaboration, rigorous experimental practice, and active participation in the growing multisensory research community.