Combining the senses: the role of experience- and task-dependent mechanisms in the development of audiovisual simultaneity perception

The brain's ability to integrate information from the different senses is essential for decreasing sensory uncertainty and ultimately limiting errors. Temporal correspondence is one of the key processes that determines whether information from different senses will be integrated and is influenced by both experience- and task-dependent mechanisms in adults. Here we investigated the development of both task- and experience-dependent temporal mechanisms by testing 7-8-year-old children, 10-11-year-old children, and adults in two tasks (simultaneity judgment, temporal order judgment) using audiovisual stimuli with differing degrees of association based on prior experience (low for beep-flash vs. high for face-voice). By fitting an independent channels model to the data, we found that while the experience-dependent mechanism of audiovisual simultaneity perception is already adult-like in 10-11-year-old children, the task-dependent mechanism is still not. These results indicate that differing maturation rates of experience-dependent and task-dependent mechanisms underlie the development of multisensory integration. Understanding this development has important implications for clinical and educational interventions.