Experimental Brain Research

, Volume 83, Issue 3, pp 598–606 | Cite as

Basic determinants for FM responses in the inferior colliculus of rats

  • P. W. F. Poon
  • X. Chen
  • J. C. Hwang


The response of 835 click-sensitive neurons in the inferior colliculus (IC) to ramp frequency modulated (FM) tones was studied in the anaesthetized rat. More than 70% of the cells were sensitive to the FM sound, and over 25% were “FM specialized”. Systematic variations of the stimulus parameters showed that sweep velocity, sweep range, and intensity of the FM signal were the 3 basic determinants for the unit response. For an“FM specialized” cell, the response pattern to each of the parameters was either monotonic or bell-shaped. The population statistics of response patterns to the FM parameters, including the tuning factors, were generated. A stimulus domain was proposed to represent the“receptive space” of the FM cells.

Key words

Frequency modulation Inferior colliculus Click-sensitive units Receptive space Rat 


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Copyright information

© Springer-Verlag 1991

Authors and Affiliations

  • P. W. F. Poon
    • 1
  • X. Chen
    • 1
  • J. C. Hwang
    • 1
  1. 1.Department of PhysiologyFaculty of Medicine, University of Hong KongHong Kong

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