Robust speech recognition using articulatory gestures in a dynamic Bayesian network framework

Articulatory Phonology models speech as spatio-temporal constellation of constricting events (e.g. raising tongue tip, narrowing lips etc.), known as articulatory gestures. These gestures are associated with distinct organs (lips, tongue tip, tongue body, velum and glottis) along the vocal tract. In this paper we present a Dynamic Bayesian Network based speech recognition architecture that models the articulatory gestures as hidden variables and uses them for speech recognition. Using the proposed architecture we performed: (a) word recognition experiments on the noisy data of Aurora-2 and (b) phone recognition experiments on the University of Wisconsin X-ray microbeam database. Our results indicate that the use of gestural information helps to improve the performance of the recognition system compared to the system using acoustic information only.