LAUSR

Formal models of human phonetic perception are often formulated at a highly abstracted, computational level of description. One cost of such an approach is that it can be exceedingly difficult to translate a “high-level” computational theory into the “low-level” neural circuitry which implicitly underpins any theory of human perception. Here we present our initial efforts to formulate a theory of phonetic perception in terms of known neurological primitives—in this case a particular mathematical characterization of the stimulus/response characteristics of neurons in mammalian auditory cortex: the spectro-temporal receptive field. We propose that phonetic categories can be modeled as ensembles of these cells, and use computer simulations to demonstrate that such an approach exhibits the psycho-acoustical warping characteristic of categorical perception. This model has no acoustic “features” as traditionally construed: no formants, no spectral moments, no MFCCs, etc. The primitive objects of this model are ...