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The shape of the pharynx has a large effect on the acoustics of vowels, but direct measurement of this part of the vocal tract is difficult. The present study examines the efficacy of inferring midsagittal pharynx shape from the position of the tongue, which is much more amenable to measurement. Midsagittal magnetic resonance (MR) images were obtained for multiple repetitions of 11 static English vowels spoken by two subjects (one male and one female). From these, midsagittal widths were measured at approximately 3-mm intervals along the entire vocal tract. A regression analysis was then used to assess whether the pharyngeal widths could be predicted from the locations and width measurements for four positions on the tongue, namely, those likely to be the locations of a receiver coil for an electromagnetometer system. Predictability was quite high throughout the vocal tract (multiple r> 0.9), except for the extreme ends (i.e., larynx and lips) and small decreases for the male subject in the uvula region. The residuals from this analysis showed that the accuracy of predictions was generally quite high, with 89.2% of errors being less than 2 mm. The extremes of the vocal tract, where the resolution of the MRI was poorer, accounted for much of the error. For languages like English, which do not use advanced tongue root (ATR) distinctively, the midsagittal pharynx shape of static vowels can be predicted with high accuracy.

The ability of speakers to exaggerate speech sounds ("hyperarticulation") has led to the theory that the targets themselves must be hyperspace hyperarticulated. Johnson, Flemming, and Wright (1993) found that perceptual "best exemplar" choices for vowels were more speech extreme than listeners' own productions. Our first experiment, using their procedure, only partially replicated their results. Low vowels vowel perception showed a higher F1, consistent with hyperspace. Front vowels also showed more frontness in F2, but back vowels were less extreme ("hypoarticulated") on F2. Our second experiment used an identification and rating of each stimulus, yielding similar results of a smaller magnitude. Our results indicate that the perceptual space is calibrated to a particular (synthetic) vowel space, which is not related straightforwardly to the speakers' spaces. The original hyperspace hypothesis can be attributed to the methodology which led to extreme judgments and of the fronting of back vowels in California English. The present results indicate that no such hypothesis is needed. Vowel targets are measurable from an individual's productions, and the individual's perception of other speakers (even synthetic ones) is based on information about the vocal tract and dialect of the speaker.

The posterior pharyngeal wall has been assumed to be stationary during speech. The present study examines this assumption in order to assess whether midsagittal widths in the pharyngeal region can be inferred from measurements of the anterior pharyngeal wall. Midsagittal magnetic resonance images and X-ray images were examined to determine whether the posterior pharyngeal wall from the upper oropharynx to the upper laryngopharynx shows anterior movement that can be attributed to variables in speech: vowel quality in both English and Japanese; vowels versus consonants as classes of speech sounds; sustained versus dynamically produced speech; and isolated words versus sentences. Measurements were made of the distance between the anterior portion of the vertebral body and the pharyngeal wall. The first measurement was on a line traversing the junction between the dens and the body of the second cervical vertebra (C2). The next three measurements were on lines at the inferior borders of the bodies of C2, C3, and C4. The measurements showed very little movement of the posterior pharyngeal wall, none of it attributable to speech variables. Therefore, the position of the posterior pharyngeal wall in this region can be eliminated as a variable, and the anterior portion of the pharynx alone can be used to estimate vocal cavities.

Phonological studies have predicted that the dorsal articulations of English /r/ and /l/ correspond with those of schwa and open o, respectively [Gick, Phonology (in press)]. Specifically, /r/ and schwa are hypothesized to share pharyngeal configuration, while /l/ and open o share upper pharyngeal/uvular configuration. To test this prediction, midsagittal MRI images of the vocal tract of a male speaker of American English were collected and midsagittal distance (of airspace above the tongue surface) measured at 44 3-mm intervals along the vocal tract length. Regions of the vocal tract were defined as pharyngeal, uvular and oral, as in Whalen et al. [JSLHR (in press)], with the pharyngeal region divided into upper and lower halves. Midsagittal distances were collected for eleven sustained vowels plus /r/ and /l/. Distances for average vowels were subtracted point by point from /r/ and /l/ and a single rms calculated within each region of the vocal tract. As predicted, in the upper pharyngeal and upper pharyngeal/uvular regions, /l/ showed the greatest correspondence with open o, while /r/ was most similar to schwa throughout the pharynx. These results support the phonological interpretation of the dorsal gestures of English liquids as vocalic. [Work supported by NIH grant DC-02717.]

While the rear pharyngeal wall has been assumed to be stationary during speech, this needs to be confirmed. The present study used midsagittal magnetic resonance images to determine whether the posterior pharyngeal wall shows vowel-specific movement during the sustained production of 11 English vowels. Distances were measured between the most posterior portion of the vertebral body and the pharyngeal wall at four points. The first traversed the junction between the dens and body of the second vertebra (C2). The next three traversed the inferior border of the bodies of C2, C3, and C4. These ranged from a level just below the velopharyngeal port to one near the larynx. In preliminary measurements for one speaker, only the uppermost location showed significant variation due to vowel quality; at the other locations, differences were less than 1 mm. Further subjects are being studied. These findings confirm, at least for vowels, the assumption that the rear pharyngeal wall is stationary during speech. Therefore, midsagittal distances in the pharyngeal region can be inferred from measurements of the anterior pharyngeal wall in relation to the fixed features of the vocal tract. [Work supported by NIH Grant DC-02717.]

The goal of the present study is to identify a novel paradigm of epistemic modal operator derived from disjunction. Our main data involves an inquisitive disjunction marker nka in Korean, the presence of which enhances a speaker’s epistemic uncertainty and forms a modalized question. We show how nka contributes the modal effects in question within a theory of nonveridicality. In particular, we propose that the prerequisite of nka are non-homogenous nonveridical states that are partitioned in equipoised epistemic spaces because of the absence in ranking between them. The distinct notions of disjunction, question, and possibility modals can thus be systematically captured under the framework of nonveridical equilibrium. The current analysis offers important insights into the relationship between the classes of nonveridical and modal ingredients involved in inquisitive disjunction: First, Korean facts importantly reveal that modalized questions do not form a uniform class with regular questions, since interrogative semantics alone cannot predict the epistemic uncertainty. Second, languages parameterize as to how they lexicalize the function of manipulating modal base. The implication of our findings is that disjunction needs to be recognized as a novel device for encoding a speaker’s weakest perspective on epistemic modality.