• Phonetics and Speech Sciences
• /
• v.9 no.3
• /
• pp.49-56
• /
• 2017

Much research attention has been directed to identify how native speakers perceive non-native speakers' oral proficiency. To investigate the generalizability of previous findings, this study examined segmental, phonological, accentual, and temporal correlates of native speakers' evaluation of L2 Korean proficiency produced by learners with various levels and nationalities. Our experiment results show that proficiency ratings by native speakers significantly correlate not only with rate of speech, but also with the segmental accuracies. The influence of segmental errors has the highest correlation with the proficiency of L2 Korean speech. We further verified this finding within substitution, deletion, insertion error rates. Although phonological accuracy was expected to be highly correlated with the proficiency score, it was the least influential measure. Another new finding in this study is that the role of pitch and accent has been underemphasized so far in the non-native Korean speech perception studies. This work will serve as the groundwork for the development of automatic assessment module in Korean CAPT system.

• Phonetics and Speech Sciences
• /
• v.12 no.1
• /
• pp.43-50
• /
• 2020

This study investigated whether listeners' perceptual patterns varied according to base token selected for stimuli manipulation. Voice onset time (VOT) and fundamental frequency (F0) values were orthogonally manipulated, each in seven steps, using naturally produced words that contained a lenis (/kan/) and an aspirated (/k^han/) stop in Seoul Korean. Both native and non-native groups showed significantly higher numbers of aspirated responses for the stimuli constructed with /k^han/, evidencing the use of minor cues left in the stimuli after manipulation. For the native group the use of the VOT and F0 cues in the stop categorization did not differ depending on whether the base token included the lenis or aspirated stop, indicating that the results of previous studies remain tenable that investigated the relative importance of the acoustic cues in the native listener perception of the Korean stop contrasts by using one base token for manipulating perceptual stimuli. For the non-native group, the use patterns of the F0 cue differed as a function of base token selected. Some findings indicated that listeners used alternative cues to identify the stop contrast when major cues sound ambiguous. The use of the manipulated VOT and F0 cues by the non-native group was not native-like, suggesting that non-native listeners may have perceived the minor cues as stable in the context of the manipulated cue combinations.

• Phonetics and Speech Sciences
• /
• v.4 no.3
• /
• pp.25-30
• /
• 2012

This study investigated whether native Korean listeners could use visual cues for the identification of the English consonants /b/ and /v/. Both auditory and audiovisual tokens of word minimal pairs in which the target phonemes were located in word-initial or word-medial position were used. Participants were instructed to decide which consonant they heard in $2{\times}2$ conditions: cue (audio-only, audiovisual) and location (word-initial, word-medial). Mean identification scores were significantly higher for audiovisual than audio-only condition and for word-initial than word-medial condition. Also, according to signal detection theory, sensitivity, d', and response bias, c were calculated based on both hit rates and false alarm rates. The measures showed that the higher identification rate in the audiovisual condition was related with an increase in sensitivity. There were no significant differences in response bias measures across conditions. This result suggests that native Korean speakers can use visual cues while identifying confusing non-native phonemic contrasts. Visual cues can enhance non-native speech perception.

• Phonetics and Speech Sciences
• /
• v.3 no.1
• /
• pp.51-65
• /
• 2011

This study attempts to investigate the interlanguage speech intelligibility benefit for listeners (ISIB-L), examining Chinese talkers' production of English liquids and its perception of native listeners and non-native Chinese and Korean listeners. An Accent Judgment Task was conducted to measure non-native talkers' and listeners' phonological proficiency, and two levels of proficiency groups (high and low) participated in the experiment. The English liquids /l/ and /r/ produced by Chinese talkers were considered in terms of positions (syllable initial and final), contexts (segment, word and sentence) and lexical density (minimal vs. nonminimal pair) to see if these factors play a role in ISIIB-L. Results showed that both matched and mismatched interlanguage speech intelligibility benefit for listeners occurred except for the initial /l/. Non-native Chinese and Korean listeners, though only with high proficiency, were more accurate at identifying initial /r/, final /l/ and final /r/, but initial /l/ was significantly more intelligible to native listeners than non-native listeners. There was evidence of contextual and lexical density effects on ISIB-L. No ISIB-L was demonstrated in sentence context, but both matched and mismatched ISIB-L was observed in word context; this finding held true for only high proficiency listeners. Listeners recognized the targets better in the non-minimal pair (sparse density) environment than the minimal pair (higher density) environment. These findings suggest that ISIB-L for English liquids is influenced by talkers' and listeners' proficiency, syllable position in association with L1 and L2 phonological structure, context, and word neighborhood density.

• Speech Sciences
• /
• v.11 no.1
• /
• pp.87-103
• /
• 2004

This study investigates Korean listeners' perception of the English stop epenthesis between the sonorant and fricative segments. Specifically this study investigates 1) how often English epenthetic stops are perceived by native Korean listeners, given the fact that Korean does not allow consonant clusters in codas; and 2) whether perception of the epenthetic stops, which are optional phonetic variations, not phonemes, could be improved without any explicit training. 120 English non-words with a mono-syllable structure of CVC1C2, where C1=/m, n, $\eta$, 1/, and C2=/s, $\theta$, $\int$/, were given to two groups of native Korean listeners, and they were asked to detect the target stops such as [p], [t], and [k]. The number of their responses were computed to determine how often listeners succeed in recovering the string of segments produced by the native English speaker. The results of the present study show that English epenthetic stops are poorly identified by native Korean listeners with low English proficiency, even in the case where stimuli with strong acoustic cues are provided with, but perception of epenthetic stops is closely related with listeners' English proficiency, showing the possibility of the improvement of perception. It further shows that perception of epenthetic stops shows asymmetry between coronal and non-coronal consonants.

• Phonetics and Speech Sciences
• /
• v.12 no.1
• /
• pp.11-17
• /
• 2020

Non-tonal language speakers may have difficulty learning second language lexical tones. In the present study, we explored this issue with Korean-speaking learners of Mandarin Chinese (i.e., non-tonal first language speakers) by examining their perception and production of Mandarin lexical tones. In the perception experiment, the Korean learners were asked to listen to the tone of each stimulus and assign it to one of four Mandarin lexical tones using the response keys; in the production experiment, the learners provided speech production data for the lexical tones and then their productions were identified by native listeners of Mandarin Chinese. Our results showed that the Korean learners of Mandarin Chinese had difficulty in perceptually distinguishing Tone 2 and Tone 3, with the most frequent production error being the mispronunciation of Tone 3 as Tone 2. We also investigated whether unfamiliar non-native phonemes (i.e., Chinese phonemes) that do not exist in the native language phonemic inventory (i.e., Korean) may hinder the processing of the non-native lexical tones. We found no evidence for such effects, neither for the perception nor for the production of the tones.

• Phonetics and Speech Sciences
• /
• v.5 no.3
• /
• pp.21-29
• /
• 2013

The mismatch negativity (MMN) is known to be a fronto-centrally negative component of the auditory event-related potentials (ERP). $N\ddot{a}\ddot{a}t\ddot{a}nen$ et al. (1997) and Winkler et al. (1999) discuss that MMN acts as a cue to a phoneme perception in the ERP paradigm. In this study a perception experiment based on an ERP paradigm to check how Korean and American English speakers perceive the American English high front vowels was conducted. The study found that the MMN obtained from both Korean and American English speakers was shown around the same time after they heard F1s of English high front vowels. However, when the same groups heard English words containing them, the American English listeners' MMN was shown to be a little faster than the Korean listeners' MMN. These findings suggest that non-speech sounds, such as F1s of vowels, may be processed similarly across speakers of different languages; however, phonemes are processed differently; a native language phoneme is processed faster than a non-native language phoneme.

• Phonetics and Speech Sciences
• /
• v.6 no.4
• /
• pp.47-52
• /
• 2014

This study investigated how the degree of attention modulates English learners' perception of Korean stop contrasts. The contributions of VOT and F0 in perceiving Korean stops were examined while availability of attentional resources was manipulated using a dual-task paradigm. Results demonstrated the attentional modulation in the use of VOT, but not in F0: under less attention, the contribution of VOT to the perception of aspirated stops decreased, whereas that of lenis stops increased, which suggests more native-like performance. This implies that the role of attention in perceiving non-native contrasts might differ depending on how equivalent the acoustic and perceptual cues are between L1 and target L2 contrasts.

• Speech Sciences
• /
• v.14 no.1
• /
• pp.105-119
• /
• 2007

The purpose of this study is to examine Korean students' production and perception of word-final stop voicing in light of their overseas experience. Subjects were English native speakers, Korean university students with residence experience in America, Korean university students without residence experience in America, and Korean elementary school students. They participated in both production and perception tests. Results showed that the students' production and perception with residence experience in America appeared quite similar to those of the English native speakers. In the production tests, we noticed somewhat different results in temporal and frequency features. The one-year residence in America had some influence on their frequency features, but not the temporal features in the word final stop production. That difference could be seen in the perception tests, too. We could not find any difference in the identification test of the final release environment between the Korean university students who had studied abroad and those who didn't. Rather the difference could be found in the cue influence test in both the final release and non-release environments.

• Phonetics and Speech Sciences
• /
• v.8 no.1
• /
• pp.19-24
• /
• 2016

The Korean high back vowels /o/ and /u/ have been reported to be in a state of near-merger especially among young female speakers. Along with cross-generational changes, the vowel position within a word has been reported to render different phonetic realization. The current study examines native English speakers' ability to attend to the phonetic cues that distinguish the two merging vowels and the positional effects (word-initial vs. word-final) on the identification accuracy. 28 two-syllable words containing /o/ or /u/ in either initial or final position were produced by native female Korean speakers. The CV part of each target word were excised and presented to six native English speakers. The results showed that although the identification accuracy was the lowest for /o/ in word- final position (41%), it increased up to 80% in word-initial position. The acoustic analyses of the target vowels showed that /o/ and /u/ were differentiated on the height dimension only in word-initial position, suggesting that English speakers may have perceived the distinctive F1 difference retained in the prominent position.