Lateral Channel Formation in Australian English /l/: Insights from Magnetic Resonance Imaging

Goals of lateral approximant production are imperfectly understood, partly because of the limitations of most existing data, restricted to the midsagittal plane. To provide more complete information about the configuration of the vocal tract for laterals, /l/-production in three vowel contexts by three Australian English speakers was examined for the first time using a combination of real-time and volumetric Magnetic Resonance Imaging (MRI). Laterals produced by all speakers were characterised by bilateral parasagittal airflow, with some asymmetries in side channel geometries. Central occlusion of the oral airway varied in location, timing, and duration across speakers and vowel contexts, but was consistently associated with reduction in overall acoustic intensity relative to context vowels. These data provide further insights into the complex relationships between articulatory, coarticulatory and acoustic properties of lateral approximants, and their realisation in Australian English.