A broad review of literature describing lingual function during speech shows that speaker samples per study are typically small (N<3 in more than 80% of all cases), and that speech samples, and representational and analysis conventions are highly variable. Similar conclusions can be drawn for other articulators. Thus it is fair to argue that there is still not available any valid, statistically-defensible sense of normal speech motor behavior, against which disordered articulatory behavior can be compared. Accordingly, a large-sample, 50-speaker x-ray microbeam speech database will be developed at the University of Wisconsin, incorporating point-parametrized representations of lingual, labial, mandibular, and velar movements in association with the resulting acoustic sound pressure wave, for a rich set of utterances and oral motor tasks, and lengthy recording interval (circa 18 min/speaker). The database is intended to be uniform across speakers in task inventory and descriptive kinematic framework; sufficiently accurate and deep to withstand scrutiny of variance, within and across speakers, and perhaps most importantly, an open source available for unlimited inspection and use by other speech scientists. Descriptions of the proposed speech inventory, experimental protocol, speaker sample, and timetable for database development will be provided. [Work supported by NIH DC00820.]

A long recognized problem for linguistic theory has been to explain why certain sounds, sound oppositions, and sound sequences are statistically preferred over others among languages of the world. The formal theory of markedness, developed by Trubetzkoy and Jakobson in the early 1930's, and extended by Chomsky and Halle (1968), represents an attempt to deal with this problem. It is at least implicit in that theory that sounds are rare when (and because) they are marked, and common when (and because) they are not. Whether sounds are marked or unmarked depends – in the latter version of the theory, particularly – upon the ‘intrinsic content’ of acoustic and articulatory features which define them. There was, however, no substantive attempt among early proponents of the theory to show what it was about the content of particular features and feature combinations that caused them to be marked, and others not.

Measurements were made of saggital plane movements of the larynx, soft palate, and portions of the tongue, from a high-speed cinefluorographic film of utterances produced by one adult male speaker of American English. These measures were then used to approximate the temporal variations in supraglottal cavity volume during the closures of voiced and voiceless stop consonants. All data were subsequently related to a synchronous acoustic recording of the utterances. Instances of /p,t,k/ were always accompanied by silent closures, and sometimes accompanied by decreases in supraglottal volume. In contrast, instances of /b,d,g/ were always accompanied both by significant intervals of vocal fold vibration during closure, and relatively large increases in supraglottal volume. However, the magnitudes of volume increments during the voiced stops, and the means by which those increments were achieved, differed considerably across place of articulation and phonetic environment. These results are discussed in the context of a well-known model of the breath-stream control mechanism, and their relevance for a general theory of speech motor control is considered.

Differences in severity between the speakers with PD and ALS may have accounted for some of the differences in movement characteristics between the groups. These factors need to be carefully considered when describing the nature of speech disorder and developing empirically based evaluation and treatment strategies for dysarthria.

No abstract