Reconstruction of Phonated Speech from Whispers Using Formant-Derived Plausible Pitch Modulation

Whispering is a natural, unphonated, secondary aspect of speech communications for most people. However, it is the primary mechanism of communications for some speakers who have impaired voice production mechanisms, such as partial laryngectomees, as well as for those prescribed voice rest, which often follows surgery or damage to the larynx. Unlike most people, who choose when to whisper and when not to, these speakers may have little choice but to rely on whispers for much of their daily vocal interaction. Even though most speakers will whisper at times, and some speakers can only whisper, the majority of today’s computational speech technology systems assume or require phonated speech. This article considers conversion of whispers into natural-sounding phonated speech as a noninvasive prosthetic aid for people with voice impairments who can only whisper. As a by-product, the technique is also useful for unimpaired speakers who choose to whisper. Speech reconstruction systems can be classified into those requiring training and those that do not. Among the latter, a recent parametric reconstruction framework is explored and then enhanced through a refined estimation of plausible pitch from weighted formant differences. The improved reconstruction framework, with proposed formant-derived artificial pitch modulation, is validated through subjective and objective comparison tests alongside state-of-the-art alternatives

INTRAORAL AIR PRESSURE MEASURES IN ADULTS

The effect of age, gender, and repeated measures on intraoral air pressure (P0) was examined. Sixty adults comprised of ten males and ten females in each of three age groups (i.e., 20 to 39, 40 to 59, and 60 to 83 years) participated. P0 was assessed during voiceless stop plosive /p/ productions in repeated vowel/consonant syllables. The three medial plosives of a seven syllable train were averaged to comprise a token. Five tokens were obtained and averaged for each of three trials. Thus each participant contributed 105 syllables and a subsequent three P0s for analyses. There was no statistically significant difference in P0 as a function of age or gender (p>.05). These findings support the conception that P0 remains stable throughout adulthood and is not dependent on gender. Differences in repeated measures of P0 attained statistical significance (p = .03), however the mean differences between trials (.23 cm H20) were negligible and deemed to be clinically insignificant. Thus, across a short sampling session, P0 is a relatively stable measurement and does not change as a function of age or gender

Altered Auditory Feedback

The purpose of the study was to determine if combining delayed auditory feedback (DAF) and frequency altered feedback (FAF) would be more fluency enhancing than either DAF or FAF alone. Ten stutterers read at normal and fast speech rates under nonaltered auditory feedback (NAF), DAF (i.e., a 50 ms delay), FAF (i.e., a one half octave downward shift), and a combination of DAF and FAF [(COMBO), i.e., a 50 ms delay plus a one half octave downward shift]. Results indicated that stuttering frequency was significantly reduced under all altered auditory conditions at both speech rates relative to the NAF condition. There was, however, no significant differences between the altered auditory feedback conditions (i.e., DAF, FAF, and COMBO). It is suggested that further studies be undertaken to explore the combination of altered auditory feedback conditions, as it may be the case that a floor effect was demonstrated with the singular presentations of DAF and FAF and further improvements in fluency enhancement could not be exhibited in the combined condition. Finally, these findings support the notion that a slowed rate of speech is not necessary for fluency enhancement under conditions of altered auditory feedback

Articulatory Abnormalities in Athetoid Cerebral Palsy

This report presents cinefluorographic data on the articulation of isolated vowels, VCV nonsense utterances, and short sentences by five subjects with athetoid cerebral palsy. Articulatory abnormalities were identified from tracings of vocal tract shapes and from displacement-by-time plots of articulatory events. The most frequent abnormalities were large ranges of jaw movement, inappropriate positioning of the tongue for various phonetic segments (especially because of a reduced range of tongue movement in the anteroposterior dimension), intermittency of velopharyngeal closure caused by an instability of velar elevation, prolonged transition times for articulatory movements, and retrusion of the lower lip. The speech disorder associated with athetosis is considered with respect to a model of motor learning.</jats:p