SRPP: Using MRI to examine the posterior place of articulation in Semitic emphatics: Pharyngealization in Arabic and ejectives in Tigrinya

(together with Marissa Barlaz, Ryan Shosted, Sharon Rose, Zhi-Pei Liang, Brad Sutton)

The phonemic inventories of many languages in the Semitic family (e.g. Arabic, Soqotri, Jibbali, Mehri) include a set of emphatic sounds (Versteegh, 2001). These are doubly-articulated speech sounds that have a primary oral constriction and a simultaneous secondary back constriction in the (velo)pharyngeal and/or glottal region. This talk will investigate the articulatory configuration associated with the secondary back constriction in two Semitic languages: Arabic and Tigrinya. The emphatics of Arabic are pharyngealized, and thus have a secondary constriction resulting from a retracted tongue root. In contrast, the secondary articulation of the Tigrinya ejectives is produced with a glottalic egressive airstream: the vocal folds are tightly adducted and the larynx is raised in a piston-like motion, thereby constricting the pharynx and increasing the supralaryngeal air pressure trapped in the cavity between the vocal folds and the oral constriction (Ladefoged, 1993). Upon release of the oral constriction, “the entrapped high-pressure air will momentarily burst forth in a short sharp explosion” (Catford, 2001:22). In Semitic cognates, pharyngealized consonants of Arabic correspond to ejective consonants in languages spoken in the Southern part of the Arabian Peninsula and the Horn of Africa (Bellem & Watson, 2014; Shosted & Rose, 2011). An example is the correspondence between pharyngealized /sˤ/ in Arabic / ħisˤaːr/ (enclosure), and ejective /s’/ in Tigrinya /ħas’ur/ (fence, enclosure).
In this study, we use ultra-fast Magnetic Resonance Imaging (MRI) based on the implementation of partial-separability models (Fu et. al., 2015) aided by automatic image processing techniques to examine and compare the back articulation of Arabic pharyngealized /sˤ/ and Tigrinya ejective /k’/. With this non-invasive method, it is possible to observe, in real-time and with high spatio-temporal resolution, the articulatory configuration and gestures that occur in the relatively inaccessible pharyngeal region of interest in this study. The results show clear retraction of the tongue root and dorsum in the case of the pharyngealized consonants of Arabic resulting in a more constricted pharynx. This is also observed in the ejective consonants of Tigrinya, in addition to forward expansion of the upper posterior pharyngeal wall. The pharynx is clearly more constricted in the latter type, reducing the volume of the supralaryngeal cavity behind the oral constriction in order to achieve the high pressure required for producing the sharp burst of ejectives.