1. Department of Psychology, University of California, San Diego, 9500 Gilman Drive, La Jolla, California 92093, USA
2. Department of Biologic and Bioacoustic Research, National Marine Mammal Foundation, 3131, 2240 Shelter Island Drive, San Diego, California 92106, USA
3. United States Navy Marine Mammal Program, Space and Naval Warfare Systems Center Pacific, 53560 Hull Street, San Diego, California 92152, USA
4. Section of Neurobiology, Division of Biological Sciences, University of California, San Diego, 9500 Gilman Drive, La Jolla, California 92093, USA
5. Department of Rehabilitation Science, University at Buffalo, 501 Kimball Tower, Buffalo, New York 14214, USA