Instructional Effects on Voice Onset Time Perception in L2 Speech Segmentation

This study examined the effects of instruction on the English word boundary perception of Korean learners of English. The focus of this study was the appropriate use of Voice Onset Time (VOT) of English voiceless stops (p, t, k) in word initial (e.g., top) and after word initial s position (e.g., stop) signaling the presence and absence of a word boundary before the stop consonant. There were 48 participants in the study, who were assessed three times: before instruction (pre-test), immediately after instruction (post-test), and five weeks after instruction (delayed post-test). Results revealed that participants’ perceptual accuracy improved significantly in both VOT positions in segmentation after instruction. However, the improvement was more prominent in word initial than after word initial s. Among word initial stop consonants, velar stops were the most difficult to acquire, while after initial s, bilabial stops were the most difficult and alveolar stops were the easiest to acquire.