Tone sensitivity & the Identification of Laryngeal Features by KFL learners

Tone sensitivity & the Identification of Consonant Laryngeal Features by KFL learners15th AATK Annual Conference Hye-Sook Lee-Presented by Hi-Sun Kim-University of Chicago1Three-way laryngeal contrasts in KoreanChallenge for KFL learnersKee-Ho Kim et al. (2006): lenis stops hardest for English learners of Korean to identify and tense stops least hard to identify.Importance of Fundamental Frequency in the three-way distinctionS.-A. Jun (2000): a phrase-initial tone depends on the laryngeal type of the initial consonantAspirated and tense obstruents High tone Plain(lenis) obstruents Low tone L H HThree-way laryngeal contrasts in KoreanImportance of Fundamental Frequency (F0) in the three-way distinctionSilva (2006): phrase-initial plain and aspirated stops are neutralized in terms of VOT and the phrase-initial tone comes into play for the distinction of the two.Mi-Ryoung Kim (2001): F0 plays an important role in the identification of plain stops, whereas other acoustic cues as well as F0 are important for the perception of aspirated stops.Objectives of this studyHow does the sensitivity to phrase-initial tone affect the laryngeal feature identification of KFL learners?Heritage vs. non-heritage studentsFirst-year vs. second-year studentsCan an intonation training improve the laryngeal feature identification of KFL learners?Experiment: StimuliRecorded two native Korean speakers4 minimal triplets: p-p-ph, t-t-th, c-c-ch, k-k-kh 24 original stimuli (12 words x 2 speakers; no change)24 modified stimuli (initial tone change)Initial tone modificationAspirated and tense: original High tone F0 lowered : originalmodified : original modifiedPlain: original Low tone F0 raised : original modified

Experiment: StimuliInitial tone modificationF0 was modified in Praat, with all the other acoustic cues unchanged.

Original F0 (pitch)modified F0 (pitch)

6Experiment: proceduresSubjects17 first-year students: 9 heritage and 8 non-heritage students3 second-year students7 native speakersSubjects listened to each token and chose one answer among three choices, plain-tense-aspirated.E.g. stimulus: (either original or modified) choices: 1. 2. 3. Experiment: Intonation trainingThe experiment was conducted twice, and all the students had a weekly intonation training in between.Weekly intonation training session15 minute session every week for 6 weeksExplicit instruction on the tone-consonant correlationAssistant helped students look at a native speakers and their own intonation contours and practice the native intonation patternPre-test and Post-testPre-test: experiment before the trainingPost-test: experiment after the trainingExperiment: Matching ratioEach stimulus was repeated 5 times in the test set.One subject has 5 responses to an identical token.Matching ratio (per stimulus and subject)Actual number of matching responses/5 (original) stimulus 4 & 1 Matching ratio: 4/5 = 80% (modified) stimulus 2 & 3 Matching ratio: 2/5 = 40%Results: Native speakersMean matching ratios

Initial tone change significantly changes the identification of the aspirated and plain series.Initial tone change does not affect the identification of the tense series.

10Results: Native speakersConfusion ratios for the modified stimuli

When the initial tone reversed, the aspirated series are most confused with the plain series, and vice versa.

Response typeStimulus type11Results: First-year heritage studentsMean matching ratios (post-test only)

Similar patterns as native speakers: aspirated and plain series are sensitive to the tone change (p.05).

14Results: First-year non-heritage studentsConfusion ratios for the modified stimuli

First-year non-heritage students respond similarly to aspirated and plain stimuli: aspirated responses about 50% of the time and plain responses about 30%. Another evidence for their non-sensitivity to tone.

15Results: Second-year non-heritage studentsMean matching ratios (post-test only)

Matching ratios of the original stimuli are low, but it is clear that the identification of all three laryngeal series is sensitive to the tone change (p.05).Significant effect with second-year studentsCorrect identification ratios improved significantly at the post-test (p