A Backpropagation Network Model of the Monaural Localization Information Available in the Bat Echolocation System

J Acoust Soc Am. 1997 May;101(5 Pt 1):2964-72. doi: 10.1121/1.418524.


The information echolocating bats receive is a combination of the properties of the sound they emit and the sound they receive at the eardrum. Convolving the emission and the external ear transfer functions produces the full spectral information contained in the echolocation combination. Spatially dependent changes in the magnitude spectra of the emission, external ear transfer functions, and the echolocation combination of Eptesicus fuscus could provide localization information to the bat. Principal component analysis was used to reduce the dimensionality of these complex spectral data sets. The first eight principal component weights were normalized, rotated, and used as the input to a backpropagation network model which examined the relative directionality of the emission, ear, and the echolocation combination. The model was able to localize more accurately when provided with the directional information of the echolocation combination compared to either the emission or ear information alone.

Publication types

  • Comparative Study
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Animals
  • Chiroptera*
  • Echolocation / physiology*
  • Nerve Net*