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Copyright restrictions may apply JAMA Ophthalmology Journal Club Slides: Amblyopia and Visual-Auditory Speech Perception Burgmeier R, Desai RU, Farner KC, et al. The effect of amblyopia on visual- auditory speech perception: why mothers may say look at me when Im talking to you. JAMA Ophthalmol. Published online September 11, 2014. doi:10.1001/jamaophthalmol.2014.3307.

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Copyright restrictions may apply Introduction Speech perception is a multimodal phenomenon, integrating auditory input with the visual input of the speakers oral and extraoral facial movement. One of the most striking demonstrations of how vision influences the perception of sound is the McGurk effect, demonstrated on the next slide. When viewing the video, keep your eyes open looking at the screen and have the speaker volume raised. Which sounds do you hear?

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Copyright restrictions may apply Introduction McGurk Effect Video

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Copyright restrictions may apply Introduction The McGurk Effect

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Copyright restrictions may apply Objective To determine whether a history of amblyopia is associated with abnormal visual-auditory speech integration. Amblyopic children were hypothesized to less frequently perceive /ta/.

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Copyright restrictions may apply Study Design: Retrospective observational study at an academic pediatric ophthalmologic clinic with an average of 4 years of follow-up. Participants: Participants were at least 3 years of age. Amblyopic participants (n = 24) had best-corrected visual acuity of 20/20 in their nonamblyopic eye. Controls (n = 9) had visual acuity of 20/20 OU. Exclusion criteria were any history of developmental delay, neurologic disorders (eg, seizure, brain injury, cerebrovascular accident, congenital malformation, neoplasm, or autism spectrum disorder), or hearing disorders. Exposures: Participants were presented with the McGurk effect video and asked to report which sound was perceived: /ka/, /pa/, or /ta/. All participants viewed the stimuli binocularly; those who wore corrective spectacles were tested while wearing them. A subset of the participants with amblyopia were additionally tested monocularly. Methods

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Copyright restrictions may apply Participants were also presented with audio-only /pa/ and /ka/ stimuli (ie, with a blank screen). Those who did not correctly perceive these stimuli in 66% of trials were excluded from analysis. Participants were also excluded if they incorrectly perceived a visual-only /pa/ stimulus (ie, with no audio) or the normal bimodal audio-visual /pa/ and audio- visual /ka/ stimuli. Participants who perceived the McGurk effect (ie, visual /ka/ with audio /pa/) in 80% of trials were considered to have normal visual-auditory fusion, whereas those who perceived the effect in