Audiovisual Speech Stimuli
Archive of many different McGurk and control stimuli
The McGurk-MacDonald effect is an audiovisual illusion. McGurk stimuli consist of an auditory syllable and an incongruent visual syllable that produce the percept of a different syllable (e.g. auditory "ba" + visual "ga" perceived as "da"). Other incongruent stimuli (e.g. auditory "ga" + visual "ba") do not produce the effect. The archive contains movies that demonstrate the effect. If you use the stimuli in a scientific publication, please cite the appropriate reference in Beauchamp:Publications. Note that some of the videos in the archive require a particular video codec that is freely available in the VLC player, available from http://www.videolan.org/vlc/
To see the stimuli without downloading the archive, you may view them on YouTube
- Auditory "ba" + Visual "ga" --> AV "da" http://www.youtube.com/watch?v=WK3T7LWIkP8
- Auditory "pa" + Visual "ka" --> AV "ta" http://www.youtube.com/watch?v=An5vvn-gcwA
Beauchamp:Stimuli for other McGurk YouTube examples.
Single-syllable audiovisual words
- Nath, AR and Beauchamp, MS. A Neural Basis for Interindividual Differences in the McGurk Effect, a Multisensory Speech Illusion. Neuroimage. 2012 59:781-787.
- Nath, AR, Fava EE and Beauchamp, MS. Neural Correlates of Interindividual Differences in Children's Audiovisual Speech Perception. Journal of Neuroscience. 2011 Sept 28;31(39)13963-13971.
The following is from the methods section of Nath and Beauchamp (2012):
Word stimuli for the localizer were selected from two hundred single-syllable words from the MRC Psycholinguistic Database with Brown verbal frequency of 20 to 200, imageability rating greater than 100, age of acquisition less than 7 years and Kucera-Francis written
frequency greater than 80 (Wilson, M., 1988. The MRC Psycholinguistic Database: Machine Readable Dictionary, Version 2. Behav. Res. Methods Instrum. Comput. 20, 6–11.). The duration of the words ranged from 0.5 to 0.7 seconds. The total length of each video clip
ranged from 1.1 to 1.8 seconds in order to start and end each video with the speaker in a neutral, mouth-closed position and to include all mouth movements from mouth opening to closing.
Here is a link to a ZIP file containing all of the words. Please contact MSB if the link is broken.
The stimuli were presented with a grey background on the monitor. If you would like to use any of the following stimuli please cite as: Basu Mallick, D., Magnotti, J.F. & Beauchamp, M.S. (2013). Wide variability in McGurk perception across stimuli. Manuscript in preparation.