Proceedings of the Annual Meeting of the Cognitive Science Society

It is well-known that the auditory perception of speech sounds is strongly influenced by the phonetic categorieswhich divide up acoustic space. This paper approaches the problem of modeling categorical perception from the ground up,using a linear model of the tuning properties of auditory neurons – the spectro-temporal receptive field (STRF). An STRFwhich discriminates voiced from voiceless stops was derived from the TIMIT corpus, and two computer simulations wereconducted to investigate its properties. In one simulation, this model neuron was found to exhibit a categorical response to alinear voice-onset-time continuum, closely tracking human behavior. In the second simulation, the STRF was found to exhibita less categorical, more linear response to a stop-voicing continuum, also in line with human behavior. These two simulationsshow that perceptual responses to speech, whether non-linear or veridical, can be modeled by the action of auditory neurons.