1. Departments of Head and Neck Surgery and Linguistics, University of California–Los Angeles, Los Angeles, California 90095-1794, USA
2. Department of Linguistics, University of California–San Diego, San Diego, California 92093-0108, USA
3. Department of Speech, Language, and Hearing Sciences, University of Arizona, Tucson, Arizona 85721, USA
4. Department of Head and Neck Surgery, University of California–Los Angeles School of Medicine, Los Angeles, California 90095-1794, USA