What accounts for individual differences in susceptibility to the McGurk effect?

The McGurk effect is a classic audiovisual speech illusion in which discrepant auditory and visual syllables can lead to a fused percept (e.g., an auditory /bɑ/ paired with a visual /gɑ/ often leads to the perception of /dɑ/). The McGurk effect is robust and easily replicated in pooled group data, but there is tremendous variability in the extent to which individual participants are susceptible to it…

By Violet A. Brown, Maryam Hedayati, Annie Zanger, Sasha Mayn, Lucia Ray, Naseem H. Dillman-Hasso, Julia F. Strand in McGurk Listening Effort