Research Article

Discrimination of phase altered targets by an echolocating Atlantic bottlenose dolphin

Published: 2013-2-1

Journal: The Journal of the Acoustical Society of America

DOI: 10.1121/1.4770250

Abstract

Sensitivity of echolocating dolphins to phase changes within echoes may be a vital piece of information when constructing echolocation models. Previous experiments have yielded ambiguous results leaving it unclear what cues might have been used by passively listening dolphins to discriminate between different phase altered signals. This study used a phantom echo generator to produce computer controlled echoes. The dolphin interacted with the system in a real echolocation task to discriminate between simulated targets that were unaltered and those that had a 180° phase shift. The frequency amplitude spectral content between the two targets was the same. There were no temporal differences between the two targets. The only cue that the dolphin could use to discriminate between them was the 180° phase shift. The dolphin preformed at a success level of 40% in discriminating the two echoes. This indicates that the 180° phase shift was not perceived.

Faculty Members

  • Paul E. Nachtigall - Marine Mammal Research Program, Hawaii Institute of Marine Biology, University of Hawaii , Kaneohe, Hawaii 96744-1106
  • Marlee Breese - Marine Mammal Research Program, Hawaii Institute of Marine Biology, University of Hawaii , Kaneohe, Hawaii 96744-1106
  • Whitlow W. L. Au - Marine Mammal Research Program, Hawaii Institute of Marine Biology, University of Hawaii , Kaneohe, Hawaii 96744-1106
  • Mark W. Muller - Salisbury University , Henson Science Hall (HS) 307, 1101 Camden Avenue, Salisbury, Maryland 21801
  • Stuart D. Ibsen - University of California San Diego , Serf Building Room 295 0435, 9500 Gilman Drive, La Jolla, California 92093

Themes

  • Phase Shift Sensitivity
  • Acoustic Signal Discrimination
  • Echolocation in Dolphins
  • Sensory Processing

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