Temporal dynamics of lateral channel formation in /l/: 3D EMA data from Australian English

This study investigated the dynamics of lateral channel formation of /l/ in Australian-accented English (AusE) using 3D electromagnetic articulography (EMA). Coils were placed on the tongue both mid-sagitally and para-sagitally. We varied the vowel precedi /l/ between /I/ and /æ/ /a.g, filbert vs. talbot, and the syllable position of /l/, e.g., /'tæl.b-t/ vs. /tæb.l-t/. The articulatory analyses of lateral /l/ show that: (1) the mid-sagittal delay (from the tongue tip gesture to the tongue middle/tongue back gesture) changes across different syllable positions and vowel contexts; (2) the para-sagittal lateralization duration remains the same across syllable positions and vowel contexts; (3) the lateral formation reaches its peak earlier than the mid-sagittal gesture peak; (4) the magnitude of tongue asymmetrical lateralization is greater than the magnitude of tongue curvature in the coronal plane. We discuss these results in light of the temporal dynamics of lateral channel formation. We interpret our results as evidence that the formation of the lateral channel is the primary goal of /l/ production.