LARYNGEAL CONTROL IN THE PRODUCTION OF THREE CLASSES OF VOICELESS STOPS, WITH OCCASIONAL REFERENCE TO BOLIVIAN QUECHUA

Four experiments were conducted to collect electromyographic signals from the intrinsic and extrinsic muscles of the larynx, as well as from the orbicularis oris superior, during the production of three classes of voiceless stop consonants: unaspirated, aspirated, and glottalized. Two phoneticians, both nonnative speakers of ejectives, produced the three classes of stops. The unaspirated stops are characterized by simultaneous voice onset, while the aspirated and glottalized stops both have long voicing lags. The results of an analysis of two of the experiments are reported. The aim of the analysis was to isolate (1)patterns of muscle activity which are common to all three classes of homorganic stops, and (2)patterns which distinguish the three classes from each other. The orbicularis oris muscle shows greater activity for labial ejectives (glottalized stops) than for the other two classes. Acceptable recordings were obtained from three intrinsic laryngeal muscles, the interarytenoid, lateral cricoarytenoid, and vocalis muscles. The interarytenoid is inactive during oral closure for all three classes, but it is markedly suppressed for the aspirated stops. It is more active for the onset of voicing following an aspirated stop. Vocalis activity parallels that of the interarytenoid for unaspirated and aspirated stops. For ejectives, the vocalis and lateralis are both especially active during oral closure, and their activity subsides after oral release. By contrast, the interarytenoid is inactive during oral closure for ejectives, and its activity peaks following release for the onset of voicing. Attempts to record from the posterior cricoarytenoid and cricothyroid were unsuccessful. Bolivian Quechua is one language that makes use of these three particular classes of voiceless stops to effect linguistic distinctions. Although the results of this study do not necessarily indicate the manner in which a Quechua speaker\u27s larynx operates in producing this three-way stop distinction, it is possible to state that this way of manipulating the larynx is one way of producing the phonetic categories of unaspirated, aspirated, and glottalized stops, such as those found in Bolivian Quechua