My research interests lie in both phonology and phonetics: the study of the sounds of different languages both as tokens in an abstract system and as the physical movements of articulators resulting in soundwaves. A central focus of my research has been the extent to which the patterns that occur in the mind (phonology) may or may not be determined by what occurs in the vocal tract or the ears (phonetics). I am particularly concerned with the problem of the mapping between phonological features and articulatory gestures. My publications have examined from this point of view a number of casual speech reductions and assimilations in different languages: final-consonant deletion and palatalization in English, vowel assimilation in the Nigerian language Igbo, palatalization in Russian.