Enhancement of speech perception in noise by periodicity processing: A neurobiological model and signal processing algorithm

Abstract

The perceived loudness of sound increases with its tonality or periodicity, and the pitch strength of tones are linearly proportional to their sound pressure level. These observations suggest a fundamental relationship between pitch strength and loudness. This relationship may be explained by the superimposition of inputs to inferior colliculus neurons from cochlear nucleus chopper cells and phase locked spike trains from the lateral lemniscus. The regularity of chopper cell outputs increases for stimuli with periodicity at the same frequency as their intrinsic chopping rate. So inputs to inferior colliculus cells become synchronized for periodic stimuli, leading to increased likelihood that..