Connectionist models of categorical perception of speech

Abstract

Responses of both human and animal listeners to synthetic stop-consonant/vowel stimuli in which voice onset time (VOT) is uniformly varied are known to be 'categorical' but an explanation of this phenomenon remains elusive. A 'composite' model consisting of a physiologically-realistic auditory model feeding its patterns of neural firing to an artificial neural network is shown to reproduce listeners' behaviour in classical categorical-perception (CP) studies. However, whether the model also reproduces the so-called boundary-shift phenomenon apparently depends upon precise details of the auditory model and so, by implication, upon peripheral auditory processing.