Abstract

The current study was planned to examine the source of difficulties in English speech perception in Koreans: the question is to determine whether perception difficulties in nonnative speech sounds occur due to the detection processing of the acoustic features or due to the mapping processing from acoustic features to phonological representations. Many previous studies reported that young infants can perceive the nonnative sound features, but after acquiring the native language, adults became insensitive to the nonnative sounds. However, other studies showed that adults having difficulty in perceiving the nonnative speech sounds could discriminate different acoustic features not existing in the native language and their perceiving ability improved after practice in perceiving the nonnative speech sounds. In this study, subjects were asked to decide whether the initial sounds of two stimulus sounds were same or not. Two sound stimuli were presented consecutively and the standard stimulus preceded the prove stimulus. In one condition(or lexical context condition), the preceding stimulus was a word. And in the other condition(or non-linguistic condition), that stimulus was a syllable length sound. In both conditions, the probe stimulus was a phoneme length sound. We reasoned that if Korean subjects' difficulty in perceiving English sounds comes from the incorrect mapping from the acoustic features of English sounds to the phonological representation and if the phonological representation in mental lexicon for English words is based on the Korean phonology structure, Korean subjects would perform this discrimination task better in the non-linguistic condition than in the linguistic condition. The result showed that in the linguistic condition subjects made more errors and slower reaction time than in the non-linguistic condition. And this result indicates that Korean subjects' difficulty in perceiving English sounds occurs due to the incorrect mapping from the acoustic features of English sounds to the phonological representation.