Lectures 1-2: Nasality: Enhancement, Position, and Place of Articulation

We propose that contour nasals such as [mb,mb] come from three principal sources. One source, articula- torily driven, comes from underlying voiced stops, as nasal venting in order to sustain voicing. The other, perceptually driven, comes from underlying nasal consonants, as shielding next to contrastively oral vow- els. Although both of these first processes are phonetically well motivated, we argue that the contoured allophones specifically arise in languages in which systemic or phonotactic restrictions allow for easy re- coverability of the corresponding underlying segment. Finally, we present a few cases of contour nasals in preconsonantal contexts that seem to be neither venting nor shielding, and suggest that these arise due to place-of-articulation enhancement in clusters, arguably behind intrusive nasals in cases like Spanish rambla (< ramla). We offer diagnostics for distinguishing nasal venting from shielding and present case studies from South American languages in which understanding such phenomena as enhancement involves analyt- ical commitments to what is contrastive in the language. We then present a maximum entropy model of loanword adaptation for nasal harmonization in languages that borrow from Portuguese, which has nasality but with no onset-vowel dependencies.