 Most of the existing studies on information processing in the auditory cortex of the bat have been done by Nobuo Suga on the mustached bat, "Pteronotus parnellii".This bat's call has both CF tone and FM sweep components.Suga and his colleagues have shown that the cortex contains a series of "maps" of auditory information, each of which is organized systematically based on characteristics of sound such as frequency and amplitude.