Though we may not always think about it, we are constantly using all of our senses to understand our surrounding environment. A large portion of the brain is devoted to sensory integration, where the signals from multiple sensory organs can be combined to create perception (Bielefeld University, 2019). An interesting example of this phenomenon is especially apparent in speech. Think about it; How many times in the past 2 years have you misheard somebody speaking through a mask? It happens to me all the time! While some of this may be due to the muffling effect of the face covering, a large part of these misunderstandings actually stems from a cognitive psychology concept called the McGurk Effect.
The McGurk Effect refers to perceptual illusions in speech that occur as a result of the dual processing of auditory and visual stimuli. The visual cues we gain from observing the movements of someones lips play a large role in how our brain understands the words (Tiippana, 2014). Further investigation into this process via neuroimaging has shown that the Superior Temporal Sulcus, a region of the brain involved in the synthesis of auditory and visual information, is heavily active when an individual experiences the McGurk Effect. In fact, the activity in this region is a good predictor of an individual’s susceptibility to this perceptual phenomenon (Jones & Callan, 2003; Nath & Beauchamp, 2012).
The McGurk effect serves as a salient reminder of how the many perceptual functions of the brain work in concert to create the realities we experience. If you are interested in experiencing this phenomenon yourself, check out this amazing video example https://www.youtube.com/watch?v=G-lN8vWm3m0.