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When people think about understanding speech, they primarily think about perceiving speech auditorily (via hearing); however, there are actually two key components to speech perception: auditory and visual. Speech perception is a multimodal process; i.e., combining more than one sense, involving the integration of auditory information and visual cues. Visual cues can supplement missing auditory information; for example, when auditory information is compromised, such as in noisy environments, seeing a talker’s face can help a listener understand speech. Interestingly, auditory and visual integration occurs all of the time, even when the auditory and visual signals are perfectly intelligible. The role that visual cues play in speech perception is evidenced in a phenomenon known as the McGurk effect, which demonstrates how auditory and visual cues are integrated (McGurk and MacDonald, 1976). Previous studies of audiovisual speech perception suggest that there are several factors affecting auditory and visual integration. One factor is characteristics of the auditory and visual signals; i.e., how much information is necessary in each signal fo