Northern Pame nasal stops manifest a [-nasal] secondary feature (i.e. prestopping and poststopping) in the environment of an oral vowel. Specifically, nasal stops following an oral vowel have two phases, an oral closure and a nasal release, while nasal stops preceeding and oral vowel loose their nasal distinction completely. In this paper, I propose an aperture analysis where a segment's closure and release may come into play in the linking of a [-nasal] feature. In addition, I suggest that Northern Pame oral vowels may be better specified as underlyingly [-nasal] while nasal vowels remain unmarked for nasality, deriving their feature specification through default rules. Finally, it is shown that the phenomenon of [-nasal] spreading is productive typologically in a similar pattern to that of Northern Pame.