Describing the production of liquid and glide speech sounds in different word positions in Turkish by using ultrasound

The aim of thesis is to define /l, r, j/ phonemes' articulation features by using two-dimensional ultrasound images. Participants who do not have any speech or language disorders and are native Turkish speakers are included in the study. 19 participants aged between 20-66 participated in the study, 7 of them were males and 12 were females. By two-dimensional ultrasound images and voice recordings, total 5472 data were analyzed for Modified Curvature Index and Procrustes metrics. Analyses were carried out with both Procrustes analysis and Modified Curvature Index. For Procrustes metrics a significant difference was found between /r/ and /l/ phonemes and /r/ and /j/ phonemes in three different positions, word initial, intervocal and word final. When Modified Curvature Index values were examined, a statistically significant difference was found between /r/ and /l/ phonemes and no significant difference was found for intervocal position. Modified Curvature Index was evaluated at word final position, it was found that there was a significant difference between /r/ and /l/ and /j/ phonemes, but there was no significant difference between /l/ and /j/ phonemes. It is identified in this thesis that how complex tongue shapes are formed by using Modified Curvature Index and Procrustes metrics and it is described according to word and syllable positions.