Journal of Comparative Physiology A

, Volume 189, Issue 11, pp 843–855 | Cite as

Can two streams of auditory information be processed simultaneously? Evidence from the gleaning bat Antrozous pallidus

  • J. R. Barber
  • K. A. Razak
  • Z. M. FuzesseryEmail author
Original Paper


A tenet of auditory scene analysis is that we can fully process only one stream of auditory information at a time. We tested this assumption in a gleaning bat, the pallid bat (Antrozous pallidus) because this bat uses echolocation for general orientation, and relies heavily on prey-generated sounds to detect and locate its prey. It may therefore encounter situations in which the echolocation and passive listening streams temporally overlap. Pallid bats were trained to a dual task in which they had to negotiate a wire array, using echolocation, and land on one of 15 speakers emitting a brief noise burst in order to obtain a food reward. They were forced to process both streams within a narrow 300 to 500 ms time window by having the noise burst triggered by the bats’ initial echolocation pulses as it approached the wire array. Relative to single task controls, echolocation and passive sound localization performance was slightly, but significantly, degraded. The bats also increased echolocation interpulse intervals during the dual task, as though attempting to reduce temporal overlap between the signals. These results suggest that the bats, like humans, have difficulty in processing more than one stream of information at a time.


Auditory scene analysis Echolocation Gleaning bat Sound localization 



We are most grateful for the assistance in statistical analyses provided by Ken Gerow and Mark Leary, the software programming by Glen McLelland and Willard Wilson, and editorial comments by Mali Yenisey and Terri Zumsteg. We also appreciate the considerable time and effort contributed by two anonymous reviewers. This research was supported by grants to Z.M.F. from the National Science Foundation (IBN-9828599) and the National Institutes of Health (R01 DC00054).


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Copyright information

© Springer-Verlag 2003

Authors and Affiliations

  • J. R. Barber
    • 1
    • 2
  • K. A. Razak
    • 1
    • 3
  • Z. M. Fuzessery
    • 1
    Email author
  1. 1.Department of Zoology and PhysiologyUniversity of WyomingLaramieUSA
  2. 2.Department of BiologyWake Forest UniversityWinston-SalemUSA
  3. 3.Department of BiologyGeorgia State UniversityAtlantaUSA

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