Animal Sonar pp 413-434 | Cite as

Target Discrimination and Target Classification in Echolocating Bats

  • J. Ostwald
  • H.-U. Schnitzler
  • G. Schuller
Part of the NATO ASI Science book series (NSSA, volume 156)


Geometrical and textural properties of reflecting targets result in a specific filtering of the echolocation sounds used by the various bat species. They are therefore represented in the temporal and spectral structure of the echoes. These echo features can be used as cues for target recognition, classification and discrimination. Target recognition and classification are perceptual processes in the bat’s nervous system that imply the extraction of characteristic echo cues and a matching process with a stored template. In the recognition task this template has to be exactly (within the limits of the sensory and processing system) matched in the echo. For target classification the bat has to produce a more generalized template where echo cues are represented within a certain bandwidth for each parameter. The combination of several of these cues acts as a general template for matching. In contrast to the recognition task it is not necessary that the bat has ever perceived a specific combination of echo cues in order to classify the target.


Auditory Cortex Auditory System Inferior Colliculus Lateral Lemniscus Wingbeat Frequency 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Plenum Press, New York 1988

Authors and Affiliations

  • J. Ostwald
    • 1
    • 2
  • H.-U. Schnitzler
    • 1
    • 2
  • G. Schuller
    • 1
    • 2
  1. 1.Lehrbereich ZoophysiologieInstitut für Biologie IIITübingenGermany
  2. 2.Zoologisches InstitutMünchenGermany

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