Different modes of vibration of the vocal folds contribute significantly to the voice quality. The neutral mode phonation, often said as a modal voice, is one against which the other modes can be contrastively described, called also non-modal phonations.This paper investigates the impact of non-modal phonation on phonological posteriors, the probabilities of phonological features inferred from the speech signal using deep learning approach. Five different non-modal phonations are considered: falsetto, creaky, harshness, tense and breathiness are considered, and their impact on phonological features, the Sound Patterns of English (SPE), is investigated, in both speech analysis and synthesis tasks. We found that breathy and tense phonation impact the SPE features less, creaky phonation impacts the features moderately, and harsh and falsetto phonation impact the phonological features the most.