Speech perception is conventionally thought to be an auditory function, but humans often use their eyes to perceive speech. We investigated whether visual speech perception depends on processing by the primary auditory cortex in hearing adults. In a functional magnetic resonance imaging experiment, a pulse-tone was presented contrasted with gradient noise. During the same session, a silent video of a talker saying isolated words was presented contrasted with a still face. Visual speech activated the superior temporal gyrus anterior, posterior, and lateral to the primary auditory cortex, but not the region of the primary auditory cortex. These results suggest that visual speech perception is not critically dependent on the region of primary auditory cortex.
Department of Communication Neuroscience, 2100 West Third Street, Los Angeles, CA 90057
1Department of Neuroanatomy, 2100 West Third Street, Los Angeles, CA 90057
2Neuroscan Labs, El Paso, TX
3Electrophysiology, House Ear Institute, 2100 West Third Street, Los Angeles, CA 90057
4Departments of Radiology and Biomedical Engineering, University of Southern California
Received 8 November 2001 accepted 19 December 2001