Assessing the reliability of an online measure of the temporal binding window of audiovisual integration.

A growing body of evidence suggests that imprecise multisensory temporal processing is associated with a range of adverse clinical outcomes. Specifically, this research has shown that the temporal binding window of audiovisual integration widens with advancing age, whereas individuals with various neurodevelopmental disorders exhibit distinctive profiles of multisensory processing when compared to their neurotypical counterparts. While this line of research has made significant inroads in emphasising the importance of multisensory processing in both typical and atypical cognition, the field would greatly benefit from the validation of web-based tools for assessing multisensory temporal processing, enabling larger sample sizes and the recruitment of typically hard-to-reach populations. Here, we assessed the reliability of a web-based version of the sound-induced flash illusion (SIFI) and examined the level of agreement between the measurements of the temporal binding window that it produces relative to those derived from the SIFI task performed under standard laboratory conditions. Our results demonstrate that both versions of the task elicit a robust SIFI effect and show a similar dependency on the stimulus onset asynchronies between the audiovisual stimuli. Furthermore, our analysis revealed strong correlations between the estimated measurements of both the width and peak amplitude of the temporal binding window derived from the online and lab-based task versions, confirming the suitability of the web-based task for assessing multisensory function. Future studies should extend the evaluation of this online implementation of the SIFI to clinical populations who exhibit impaired multisensory temporal processing, to assess its suitability for clinical research.