Functional Organization of the Auditory Cortex

Representation Beyond Tonotopy in the Bat
  • Nobuo Suga
Part of the Cortical Sensory Organization book series (CSO, volume 3)


The properties of an acoustic signal produced by an animal can be studied by examining the output of a microphone displayed on the screen of an oscilloscope. Such an examination, however, gives us only limited information about the signal properties, so that the signal is usually analyzed with a spectrum analyzer. The spectrum analyzer has many filters tuned to different frequencies and it expresses the output of each as a function of time. Therefore, the properties of the acoustic signals are expressed by a pattern that appears in three coordinates: frequency, amplitude and time. To recognize individual acoustic patterns with an instrument, information-bearing elements (elements characterizing the signal) are first extracted and then their combinations are examined. The question next arises: how are acoustic signals analyzed and processed in the auditory system?


Auditory Cortex Functional Organization Constant Frequency Tuning Curve Tone Burst 
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Copyright information

© The HUMANA Press Inc. 1982

Authors and Affiliations

  • Nobuo Suga
    • 1
  1. 1.Department of BiologyWashington UniversitySt. LouisUSA

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