Abstract
Articulatory underpinnings of periodicities in the speech signal are unclear beyond a general alternation of vocal tract opening and closing. This study evaluates a modulatory articulatory signal that captures instantaneous change in vocal tract posture and its relation with two acoustic oscillatory signals, comparing stabilities to the progression of vowel and stressed vowel onsets. Modulatory signals can be calculated more efficiently than labeling linguistic events. These signals were more stable in periodicity than acoustic vowel onsets and not different from stressed vowel onsets, suggesting that an articulatory modulation function can provide a useful method for indexing foundational periodicities in speech without tedious annotation.