An experimental study of tongue body loops in V1-V2-V1 sequences

Abstract

Loops are well known as the elliptical tongue fleshpoint paths in vowel-consonant-vowel (VCV) sequences with a velar consonant. However, the discussion about the relative influences of aerodynamics, active motor control and biomechanics on loops is controversial. In order to characterize the biomechanical influence, the design of the current study was specifically based on V1-V2-V1 sequences with no consonants involved, recorded by means of electromagnetic articulography (EMA). In this context, we found evidence that the loop shape varies systematically with the angle of the main movement line between the vowels V1 and V2. Moreover, the regular angle-dependence of the loop shape is examined for eleven male and seven female German adults under different conditions for speaking rate (normal and slow) and for jaw mobility (large, small and no bite block). Model simulations suggest that both the loops and the angle-dependence of their shape can be attributed to biomechanical properties of the extrinsic tongue muscles.