Roy D. Patterson
John Holdsworth
Michael Allerh
MRC Appl. Psychol. Unit, 15 Chaucer Rd., Cambridge CB2 2EF, UK
A psychoacoustic model of auditory processing has been developed to summarize peripheral processing and provide a convenient auditory simulator for research on real-world sounds like music and speech. Most of the processing is devoted to simulating the operation of the cochlea in a fairly traditional way, that is, with a bank of auditory filters and a bank of neural transduction units. The remainder is devoted to two novel processes: First, a form of quantized temporal integration introduced to account for the stablity of the auditory images produced by periodic sounds. Second, a spiral pitch processor that operates on the auditory image and measures the loudness, pitch, and strength of voicing in speech. The system is modular and offers displays of the auditory representation of the sound at each processing stage. Standard workstations process sentence length sounds promptly with larger databases processed overnight. The system is currently being used to assess vocal agitation in samples of normal and emotional speech.