Korean Adaptation of Japanese Plosives Followed by a H or L Vowel

Japanese is a pitch-accent language with H and L tones of lexical pitch-accent described in terms of F0 (e.g. McCawley 1968; Haraguch 1977) and has a phonemic voicing contrast (e.g. hake 'brush' vs. hage 'bald'). In contrast, Korean has no voicing contrast but the three-way phonation contrast (i.e. lenis, aspirated and fortis) in plosives which are all voiceless. In addition, Korean has no lexical pitch-accent in most of dialects such as Seoul Korean which has been considered as standard Korean except for the Kyungsang dialect in South Korea (e.g. K. Chung 1980). Given the differences between Japanese and Korean, the present study aims to explore how Japanese voiced and voiceless plosives followed by a H or L vowel are borrowed into Korean in both word-initial and word-medial positions. For this purpose, we conducted a perception experiment in which one hundred sixty native speakers of Seoul and Kyungsang Korean – eighty in each group (40 male and 40 female) – participated. As test words, two-, three-and four-syllable Japanese words were used with the plosives /b d g t k/ across the contexts, as shown in (1) (an accent is marked with ''' after an accented vowel). Both the original pitch contours in the test words and resynthesized pitch contours were used as Japanese stimuli, as in Figure 1. It is found that, no matter whether they command a pitch-accent Kyungsang or Seoul Korean, all subjects mostly perceived Japanese voiced plosives as lenis in both word-initial and word-medial positions with the preference for L in the former and no significant H/L difference in the latter. On the other hand, they mostly categorized word-initial Japanese voiceless plosives as aspirated with the significant effect of H at each level of syllable length and word-medial voiceless plosives as either aspirated or fortis with no H/L effect, regardless of dialect differences (see Figures 2 and 3 for Seoul subjects' categorization). Based on the results, we propose that the H/L tonal distinction is made, as enhancement, in Accentual Phrase (AP)-initial position at a prosody in Korean adaptation of Japanese plosives and that other acoustic properties are primarily parsed for cues to L1 laryngeal features at a segment level. That is, the difference in VOT between the word-initial Japanese voiceless and voiced plosives is primarily parsed for cues to the L1 feature [±s.g.] at a segment level with the enhancement of the AP-initial H and L tones by …


Introduction
In loanword phonology the effects of L2 (i.e.donor language) prosody or segments on L1 (i.e. a host language) adaptation have been investigated (e.g.Polivanov 1931;1974;Trubetzkoy 1939;Hyman 1970;Silverman 1992;Paradis & LaCharité 1997;Davis et al. 2012).In the Korean literature, for example, Kenstowicz & Sohn (2001), Lee (2009) and Davis & Lee (2010) among others have examined how English stress or Japanese pitchaccent is borrowed into Kyungsang Korean, and Kang (2003), Ito et al. (2006) and H. Kim (2006;2007;2008;2009;2014;2017a;b) have discussed how English, French or Japanese consonants are borrowed into Korean.Some research has extended its focus on how prosodic and segmental factors do interact in L2 adaptation (e.g.Anderson-Hsieh et al. 1992;Munro & Derwing 1999;Cutler 2005;Munro 2008;Caspers & Horłoza 2012).It is in this vein that the present study is concerned with how Japanese H/L tones and segmental voicing contrast affect Korean categorization of Japanese plosives followed by a H or L vowel.
(1) Japanese (a) and Korean (b) plosives a. voiceless: p t k voiced: b d g b. lenis: p t k aspirated: p h t h k h fortis: p' t' k' Another difference between the two languages is that Japanese is a pitch-accent language, whereas Korean is not except for a few dialects.Japanese has H and L tones of lexical pitch-accent (e.g.McCawley 1968;Haraguchi 1977;1991;Shibatani 1990;Kubozono 1995;2011;Tsujimura 1996).For example, the lexical pitch of Tokyo Japanese is a twoway contrast in (a) two-syllable words, a three-way contrast in (b) three-syllable words and a four-way contrast in (c) four-syllable words, when syllables are light, as shown in (2).Words with an accent are marked with ''' after an accented vowel, as in /a'me/.The accented vowels have a H tone with preceding and following vowels having H and L, respectively.Yet, the pitch of the first syllable of a word is low unless the accent is placed on that syllable by virtue of the Initial Lowering Rule (Haraguchi 1977;1991).The pitch of the first syllable of a Japanese word is also high when the syllable is heavy and has a sonorant in coda position (e.g./kaisya/ HHH 'company'; /kantan/ 'ease' HHH). 2   (2) Pitch-accent and tones in Tokyo Japanese (Shibatani 1990

Participants
One hundred sixty native speakers of Seoul and Kyungsang Korean -eighty in each group (40 male and 40 female) -participated in the present perception experiment.Among the Kyungsang subjects, twenty-nine (16 male and 13 female) were from North Kyungsang and fifty-one from South Kyungsang (24 male and 27 female).All of the Korean subjects were university students in their twenties.The average age of the Seoul subjects was 22.6 years old and that of the Kyungsang subjects 21.1 years old when our experiment was conducted at a university in Seoul, Korea.As for our Kyungsang subjects, we recruited only Kyungsang subjects whose stay in Seoul was less than six months, because we assumed that their Kyungsang Korean would not have been contaminated yet by Seoul Korean since they just recently left their hometown for their undergraduate studies in Seoul.None of our Seoul and Kyungsang subjects had had any hearing impairments, and they had never learned Japanese, either.

Procedure
The test words were put in a frame sentence /korewa __desu/ 'This is __' and randomized.When followed by other words, the distinction between unaccented and final-accented words are realized on the surface in Japanese, as in /date desu/ LH HL vs. /bate' desu/ LH LL.Since the test words in (3) were cut off from the frame sentence in the present experiment, the distinction was not considered in this study.A male native speaker of Tokyo Japanese in his early 30s recorded the test words five times with no pause in the frame sentence at the soundproof recording room in the Laboratory of Phonetics and Phonology, CNRS/Sorbonne-Nouvelle (University of Paris 3).The recording was made at a sampling rate of 48 kHz and at a quantization of 16 bit using an Audio-technica AT8033 microphone.The recorded data were then resampled at 24 kHz.
The third repetitions of the five-time recorded test words were selected, and then F0 manipulations were made, using PSOLA in the phonetic analysis software Praat, as follows: HL for the two-syllable words; HLL for the three-syllable words except for /bake'ru/ as HLH; and HLLL for the four-syllable words except for /todoke'ru/ in (3) as HLLH.When pitch contours were changed, the Japanese speaker who recorded the test words in (3) and who is a trained phonetician checked all F0 manipulations and determined which resynthesized stimuli sounded natural in Tokyo Japanese.Thus, the resynthesized stimuli used for the present perception experiment were selected as natural based on the hearing judgment of the native speaker.In addition to the resynthesized stimuli, we also used the original pitch contours in the test words in (3) as Japanese stimuli in the present experiment.Therefore, the H and L distinction was made not only in word-initial position but also in word-medial position in the Japanese stimuli (i.e.LH vs. HL for two-syllable words; LHH vs. HLL or LHL vs. HLH for three-syllable words; LHHH vs. HLLL or LHHL vs. HLLH for four-syllable words).
The average F0 difference between H and L in the first and second vowels of all the Japanese stimuli was 30.9 Hz, and those between H and H, and L and L in the second, third and fourth vowels of the three-and four-syllable test words were 4.6 Hz and 6.2 Hz, respectively, when F0 was measured in the middle of each vowel.For example, Figure 1 shows the alignment of F0 movements in the Japanese word /katagami/ with the original pitch LHHH (Figure 1a) and a HLLL F0 manipulation (Figure 1b).The total number of stimuli was 36 (18 test words with original pitch contours in (3) +18 resynthesized ones), and two repetitions of the stimuli were randomized at a foursecond interval for one session.A total of 216 trials ((36 stimuli × 2 repetitions for one session) × 3 sessions) was presented to each participant.Thus, each stimulus was repeated six times in succession when each subject participated in the present perception experiment.In a quiet room, each subject was notified that Japanese words would be given and asked to listen to the prepared stimuli, using a headphone (HD 202 SENNHEISER or Shure SRH440) and to write them down in Korean orthography.The perception experiment was run using Praat's ExperimentMFC facility.

Results
For the comparison of the Seoul and Kyungsang subjects' categorization of Japanese plosives followed by a H or L vowel, we conducted a mixed-effect logistic regression model with Dialect (Seoul, Kyungsang), H/L and Dialect by H/L interaction as independent variables and the subjects' categorization as a dependent variable.

Korean subjects' responses for word-initial Japanese voiced plosives
Both Seoul and Kyungsang subjects mostly perceived the word-initial Japanese voiced plosives [b], [d], and [g] as lenis, no matter whether they are followed by a H or L vowel, as shown in Figure 2.Among the total four thousand eight hundred tokens (10 test words (i.e.bate, date, gaka, bakeru, dokuga, gogaku, bakamono, botebote, dakareru and gatagata) × 80 subjects (in each dialect group) × 6 repetitions) of the word-initial Japanese voiced plosives with a H vowel, the Seoul and Kyungsang subjects perceived 89% and 90.8%,  Kyungsang subjects respectively, as the lenis /p/, /t/ or /k/. 4 As for the Japanese plosives with a L vowel, the Seoul subjects perceived 91%, and the Kyungsang subjects perceived 89.3% as lenis. 5able 1(a) shows that there is no statistical difference in L between the Seoul and Kyungsang subjects' responses as lenis (β = 0.358, p = 0.170), and that the Kyungsang subjects' responses are significantly higher when the Japanese plosives are followed by H (β = 0.207, p = 0.006). 6The H/L difference is significant between the Seoul and Kyungsang subjects' responses (β = -0.449,p < 0.001), indicating that the Seoul subjects' are significantly higher when the plosives are followed by L (β = -0.242,i.e., -0.449 + 0.207).
The statistical results of Seoul subjects' categorization are shown in Table 1(b).They significantly categorized the word-initial voiced plosives as lenis in the four-syllable words when followed by a L vowel rather than when followed by a H vowel (β = -0.548,p < 0.001).Their responses as lenis are statistically higher in the two-and three-syllable words than in the four-syllable words when followed by L (β = 0.614, p < 0.001 for Syllable 2; β = 0.654, p < 0.001 for Syllable 3).The interaction of H/L and Syllable is also statistically higher in the two-and three-syllable words than in the four-syllable words (β = 0.853, p < 0.001 for H*Syllable 2; β = 0.430, p = 0.029 for H*Syllable 3).This means that the magnitude of H/L difference significantly reduces to 0.305 (i.e.-0.548 + 0.853) in the two-syllable words and to -0.118 (i.e.-0.548 + 0.430) in the three-syllable words, favoring H in the former and L in the latter.The probability of their categorization as lenis is shown in Figure 3(a).In the two-and three-syllable words, there is no tonal effect.Yet, the word-initial Japanese voiced plosives in the four-syllable words were significantly perceived as lenis, when followed by L. 7The Kyungsang subjects' categorization is not statistically different in the four-syllable words, no matter whether the plosives are followed by a H or a L vowel (β = -0.194,p = 0.070), as shown in Table 1(c).Their responses as lenis are statistically higher in the twoand three-syllable Japanese words than in the four-syllable words when followed by L (β = 0.358, p = 0.004 for Syllable 2; β = 0.498, p < 0.001 for Syllable 3).The interaction of H/L and Syllable is also significant in the two-syllable words (β = 1.041, p < 0.001 for H*Syllable 2) and in the three-syllable words (β = 0.646, p = 0.001 for H*Syllable 3), compared to the four-syllable words.This indicates that the magnitude of H/L difference significantly reduces to 0.847 (i.e. -0.194 + 1.041) and 0.452 (i.e. -0.194 + 0.646) in the twoand three-syllable words, respectively, favoring H.The probability of their categorization as lenis is given in Figure 3(b).The Kyungsang subjects significantly perceived word-initial Japanese voiced plosives as lenis when followed by a H vowel in the two-and three-syllable words, and there is no such H/L effect in the four-syllable Japanese words.
Recall that there were fifty-one from South Kyungsang (SK) and twenty-nine from North Kyungsang (NK) among our eighty Kyungsang subjects.From our mixed-effect logistic regression model with Dialect (SK, NK), H/L and Dialect by H/L interaction as independent variables and the subjects' categorization as lenis plosives as a dependent variable, we have found that there is no statistical difference in L between South and North Kyungsang subjects (β = 0.645, p = 0.068) and that the H/L difference in the NK subjects' responses is not statistically different from that in the SK subjects' (β = -0.068,p = 0.655), as shown in Appendix 2(a) (see also Appendix 2b, c and d for the other examined contexts).This leads us to consider the South and North Kyungsang subjects as a homogeneous group in the present study.

Korean subjects' responses for word-initial Japanese voiceless plosives
When Japanese words begin with the voiceless plosives [k] and [t], our Seoul and Kyungsang subjects largely perceived the plosives as aspirated, regardless of whether the plosives are followed by a H or a L vowel, as in Figure 4.Among the total two thousand eight hundred eighty tokens (6 test words (i.e.kabe, tada, kotoba, tadami, katagami and todokeru) × 80 subjects (in each dialect group) × 6 repetitions) of the word-initial Japanese b.
voiceless plosives with a H vowel, the Seoul and Kyungsang subjects perceived 95.3% and 96.1%, respectively, as the aspirated /k h / or /t h /.When the Japanese plosives are followed by a L vowel, the Seoul subjects perceived 89.7%, and the Kyungsang subjects 93.3% as aspirated. 8he difference in L between the Seoul and Kyungsang subjects' categorization of the Japanese plosives is statistically significant (β = -0.825,p = 0.007), as in Table 2(a).Kyungsang subjects' categorization is significantly higher when the Japanese plosives are followed by H than when followed by L (β = 0.797, p < 0.001).The interaction of H/L and Dialect is not significant (β = 0.346, p = 0.077), indicating that the H/L difference is not significant between the Seoul and Kyungsang subjects' responses.That is, the Seoul subjects' responses favor H (β = 1.13, i.e. 0.346 + 0.797) like the Kyungsang subjects'.
The statistical results of Seoul subjects' categorization are shown in Table 2(b).H is significantly favored in the four-syllable words (β = 0.789, p < 0.001), and their responses are statistically higher in the two-syllable words than in the four-syllable words when followed by L (β = 0.499, p = 0.008) and not significant in the three-syllable words (β = -0.299,p = 0.071).The interaction of H/L and Syllable is significant in the two-syllable words (β = 1.256, p < 0.001 for H*Syllable 2) and not significant in the three-syllable words (β = 0.349, p = 0.210 for H*Syllable 3), compared to the foursyllable words.This indicates that the magnitude of H/L difference significantly reduces to 2.045 (i.e.0.789 + 1.256) in the two-syllable words and non-significantly to 1.138 (i.e.0.789 + 0.349) in the three-syllable words.In other words, H is significantly favored in the two-and three-syllable words, as in the four-syllable words.The probability of their categorization as aspirated is presented in Figure 5(a).It is noteworthy that the two lines Japanese voiceless plosives as aspirated when a following vowel is H or L.

95.3%
(2,744/2,880) 89.7% (2,584/2,880) 96.1% (2,768/2,880) 93.3% for H and L fall apart at each level of syllable length with the line for H above that for L. This means that the Seoul subjects significantly perceived the word-initial Japanese voiceless plosives as aspirated when the plosives are followed by H rather than by L, regardless of the number of syllables in Japanese words.
In the Kyungsang subjects' categorization, H is significantly favored in the four-syllable words (β = 0.642, p = 0.006), and their responses as aspirated are statistically higher in the two-syllable words than in the four-syllable words when followed by L (β = 0.885, p < 0.001) and not significant in the three-syllable words (β = -0.109,p = 0.603), as in Table 2(c).The interaction of H/L and Syllable is not statistically higher in the two-and three-syllable words than in the four-syllable words (β = 0.470, p = 0.246 for H*Syllable 2; β = 0.209, p = 0.530 for H*Syllable 3), indicating that H is significantly favored in the two-and three-syllable words, as in the four-syllable words.The probability of their categorization reveals that the two lines for H and L fall apart at each level of syllable length with the line for H above that for L, as in Figure 5(b).Like the Seoul subjects, the Kyungsang subjects had better categorization of the word-initial Japanese voiceless plosives at each level of syllable length when a tone in a following vowel is H.

Korean subjects' responses for word-medial Japanese voiced plosives
As in word-initial position, both the Seoul and Kyungsang subjects largely tended to perceive the word-medial Japanese voiced plosives [b], [d] and [g] as the lenis /p/, /t/, and /k/, respectively, regardless of whether a following vowel has H or L, as shown in Figure 6.Among the total five thousand seven hundred sixty tokens (12 test words (i.e.kabe, tada, mago, kotoba, nakaba, tadami, dokuga gogaku, botebote, todokeru, katagami and gatagata) × 80 subjects (in each dialect group) × 6 repetitions) of the word-medial Japanese voiced plosives with a H vowel, the Seoul and Kyungsang subjects perceived 92.2% and 93.6%, respectively, as the lenis /p/, /t/ or /k/.When the Japanese plosives are followed by a L vowel, the Seoul subjects perceived 91.5%, and the Kyungsang subjects 93.2% as lenis. 9 From the statistical results in Table 3(a), we can note that the difference in L between the Seoul and Kyungsang subjects' responses is not significant (β = -0.406,p = 0.096) and that there is no tonal effect in Kyungsang subjects' responses (β = 0.090, p = 0.253).The H/L difference is not significant either (β = -0.015,p = 0.886), indicating that there is no tonal effect in the Seoul subjects' responses as in the Kyungsang subjects'.
In the Seoul subjects' categorization, H is significantly favored in the four-syllable words (β = 0.315, p = 0.026), and their responses as lenis are statistically higher in the threesyllable words (β = -0.515,p < 0.001 for Syllable 3) than in the four-syllable words when followed by L and not significant in the two-syllable words (β = 0.060, p = 0.680 for Syllable 2), as in Table 3(b).The interaction of H/L and Syllable is not statistically higher in the two-syllable words than in the four-syllable words (β = -0.060,p = 0.783 for 9 See Appendix 4 for the distribution of Seoul and Kyungsang subjects' responses when the word-medial Japanese voiced plosives are followed by a H or L vowel.

92.2%
(5,311/5,760) 91.5% (5,268/5,760) 93.6% (5,394/5,760) 93.2% Kyungsang subjects H*Syllable 2) and statistically higher in the three-syllable words (β = -0.414,p = 0.016 for H*Syllable 3).This means that the magnitude of H/L difference significantly reduces to -0.099 (i.e.-0.414 + 0.315) in the three-syllable words, favoring L. The probability of their categorization as lenis is given in Figure 7(a).The only significant tonal effect is in the four-syllable words when followed by a H vowel.In the two-and three-syllable words, there is no tonal effect.In the Kyungsang subjects' categorization, there is no tonal effect in the four-syllable words (β = 0.015, p = 0.931), and their responses as lenis are statistically higher in the two-and three-syllable words than in the four-syllable words when followed by L (β = -0.889,p < 0.001 for Syllable 2; β = -0.912,p < 0.001 for Syllable 3), as in Table 3(c).The interaction of H/L and Syllable is statistically higher in the two-syllable words than in the four-syllable words (β = 0.460, p = 0.050 for H*Syllable 2) and not significant in the three-syllable words (β = -0.081,p = 0.692 for H*Syllable 3).That is, the magnitude of H/L difference significantly reduces to 0.475 (i.e.0.460 + 0.015) in the two-syllable words, favoring H.The probability of their categorization as lenis is shown in Figure 7(b).The Kyungsang subjects significantly perceived word-medial Japanese voiced plosives as Japanese voiced plosives as lenis when a following vowel is H or L.
lenis when followed by a H vowel only in the two-syllable words.In the three-and foursyllable Japanese words, the difference in H and L did not affect their categorization of the plosives as lenis.

Korean subjects' responses for word-medial Japanese voiceless plosives
In the case of the word-medial Japanese voiceless plosives [k] and [t], both the Seoul and Kyungsang subjects largely perceived them as either aspirated or fortis, that is, /k h / or /k'/ and /t h / or /t'/, respectively, no matter whether the plosives are followed by a H or L vowel, as in Figure 8(a).Among total seven thousand six hundred eighty tokens (16 test words (i.e. gaka, bate, date, bakeru, dokuga, gogaku, nakaba, kotoba, bakamono, botebote, dakareru, gatagata, katagami and todokeru) × 80 subjects (in each dialect group) × 6 repetitions) of the word-medial Japanese voiceless plosives with a H vowel, the Seoul and Kyungsang subjects perceived 97% and 96.4%, respectively, as either aspirated or fortis.When the Japanese voiceless plosives are followed by a L vowel, the Seoul subjects perceived 96.4%, and the Kyungsang subjects 95.8%. 10he distribution of Seoul subjects' responses showed that, when followed by a H vowel, 56.9% were perceived as fortis and 43.1% as aspirated, and that when followed by a L vowel, 59.2% as fortis and 40.8% as aspirated, as shown in Figure 8(b). 11The similar distribution of Kyungsang subjects' responses was found: when followed by a H vowel, 53% were perceived as fortis and 47% as aspirated, and when followed by a L vowel, 50.7% were perceived as fortis and 49.3% as aspirated, as in Figure 8(c).
The difference in L between Seoul and Kyungsang subjects' responses is not statistically significant (β = 0.265, p = 0.405), and there is no tonal effect in Kyungsang subjects' categorization of the word-medial Japanese voiceless plosives (β = 0.157, p = 0.080), as shown in Table 4(a).The interaction of H/L and Dialect is not significant either (β = 0.077, p = 0.565), indicating that the H/L difference in the Seoul subjects' responses is not statistically different from that in the Kyungsang subjects'.
The statistical results of Seoul subjects' categorization are shown in Table 4(b).The Seoul subjects had no H/L tonal effect in the four-syllable words (β = 0.212, p = 0.080).The interaction of H/L and Syllable is not significantly higher in the two-and three-syllable words (β = -0.127,p = 0.639 for H*Syllable 2; β = 0.309, p = 0.268 for H*Syllable 3) than in the four-syllable words, indicating that the H/L difference in the former is not statistically different from that in the latter.The probability of their categorization as either aspirated or fortis is presented in Figure 9(a).The two lines for H and L are almost overlapped at each level of syllable length.In other words, there is no tonal effect on the Seoul subjects' categorization of the Japanese plosives as either aspirated or fortis, regardless of the number of syllables in Japanese words.
Like the Seoul subjects, the Kyungsang subjects had no H/L tonal effect in the foursyllable words (β = 0.108, p = 0.385) and no significant interaction of H/L and Syllable in the two-and three-syllable words, compared to the four-syllable words (β = 0.011, p = 0.959 for H*Syllable 2; β = 0.199, p = 0.373 for H*Syllable 3), as in Table 4(c).The probability of their categorization is presented in Figure 9(b) where the two lines for H and L at each level of syllable length is almost completely overlapped, as in Figure 9(a).Thus, the H and L tonal distinction has no effect on the Kyungsang subjects' categorization of the word-medial Japanese voiceless plosives, regardless of the number of syllables in Japanese words, as in the Seoul subjects' categorization.To sum up, we have noted in this section that the Seoul and Kyungsang subjects' categorization of word-initial Japanese voiceless plosives as aspirated is significantly affected by H and that their categorization of word-medial Japanese voiceless plosives as either aspirated or fortis is not affected by the H/L difference, no matter whether Japanese words are two, three or four syllables in length.Their categorization of word-medial Japanese voiced plosives as lenis is not significantly affected by the H and L tonal difference, either.In the case of word-initial Japanese voiced plosives, the Seoul and Kyungsang subjects' categorization as lenis showed that the former favored L and the latter H.In the next section, these results are discussed.

Discussion
First, as for Seoul subjects' categorization of Japanese plosives followed by a H or L vowel, we propose that the Korean prosodic unit of AP and laryngeal features do interact, such that the H/L tonal distinction is made, as enhancement, in AP-initial position, and other acoustic properties (i.e.VOT and closure duration) are primarily parsed for cues to Korean laryngeal features.Given that it is only in word-initial position that the difference in H and L affects the Seoul subjects' categorization of Japanese plosives, we suggest that the H/L tonal Japanese voiceless plosives as either aspirated or fortis plosives when a following vowel is H or L.
distinction is made in AP-initial position in their adaptation of the Japanese plosives followed by a H or L vowel.Recall that the Japanese test words in (3) were put in the frame sentence /korewa __desu/ 'This is ___' and that they were cut from the frame sentence and presented in isolation in the present experiment.The Japanese carrier sentence is phrased as one Intonational Phrase (henceforth, IP) with two APs in a lower prosodic domain, that is, IP [ AP [korewa] AP [__desu]] in an autosegmental-metrical model of intonation (e.g.Pierrehumbert 1980;Beckman & Pierrehumbert 1986;Pierrehumbert & Beckman 1988). 12Following the Strict Layer Hypothesis (Selkirk 1986) that the beginning and end of each higher domain is also the beginning and end of lower domains, the word-initial plosives of the Japanese test words presented to Korean subjects are in IP-and hence AP-initial position. 13Thus, our Seoul subjects' sensitivity to the H vs. L distinction in word-initial Japanese plosives suggests that the Korean prosodic unit of AP plays a role in their categorization of the Japanese plosives, as in the native grammar.We also propose that other acoustic properties are primarily involved in the Seoul subjects' categorization of word-initial Japanese plosives with the AP-initial H and L tones as enhancement.As for the other acoustic properties, the examination of Voice Onset Time (VOT) (i.e. the time between the release of a consonant and the onset of voicing in a following vowel) (e.g.Ladefoged 2001) and closure duration of the five-repeated Japanese tokens in (3) revealed that the difference in VOT between word-initial Japanese voiced and voiceless plosives is 31 ms and that in closure duration is 2 ms, as shown in Table 5(a).In the case of word-medial Japanese voiced and voiceless plosives, the difference in closure duration is 28 ms and that in VOT is 9 ms, as in Table 5(b). 14 The acoustic properties of VOT and closure duration are articulatorily correlated with glottal opening and linguopalatal or lip contact duration, respectively, in Korean (Kim et al. 2005;2010;2018). 15Given that VOT results from glottal opening and that glottal opening peak is significantly higher in aspirated plosives than in non-aspirated plosives (Kim et al. 2018), aspirated plosives are specified as [+spread glottis] (henceforth, [+s.g.]), and 12 In intonational phonology, it has been assumed that Syllables are grouped into Words, Words into APs, and APs into IPs. 13In Korean, most APs have three or four syllables and one or two content words (e.g.Jun & Fougeron 2000;S. Kim 2004), and in Japanese most APs have four or five syllables (e.g.Pierrehumbert & Beckman 1988;Venditti 2005;Ueyama & Jun 1998;Warner et al. 2010). 14Recall that the closure duration of word-initial Japanese voiceless plosives could be measured, because in our recording of the test words in (3), the native speaker of Tokyo Japanese was asked not to make a pause in the whole frame sentence /korewa ___desu/ 'This is ___'. 15According to MRI studies on Korean stops, Kim et al. (2005;2010) have found that glottal opening is larger in aspirated than in lenis and fortis plosives and that lip closure or linguopalatal contact is longer in aspirated and fortis plosives in concomitant with vertical laryngeal movements higher than in lenis counterparts in both word-initial and word-medial plosives.See also Kim et al. (2018) for ePGG, aerodynamic and acoustic data for the three-way phonation contrast in Korean plosives.What they have found is that aspirated plosives are significantly different from lenis and fortis ones in glottal opening peak, airflow peak height and duration of aspiration as well as VOT.(4) The laryngeal feature specification of Korean stops (Kim et al. 2005;2010;2018) lenis aspirated fortis a. [s.g.] - From the data in Table 5 and the primary acoustic cues of VOT and closure duration to the features [±s.g.] and [±tense], respectively, as in (4), we suggest that the difference in VOT between the word-initial Japanese voiceless and voiced plosives is primarily parsed for cues to the Korean laryngeal feature [±s.g.] with the enhancement of the AP-initial H and L tones by virtue of the feature [±tense], as schematized in (5a).That is, in the Seoul subjects' categorization of word-initial Japanese voiceless plosives as aspirated, long VOT ([+s.g.]) plays a primary role, being parsed for cues to the feature [+s.g.], and the APinitial H enhances it by virtue of the feature [+tense].Thus, the Japanese plosives are categorized as aspirated ([+s.g., +tense]), as in (5a i).In the case of their categorization of word-initial Japanese voiced plosives, we suggest that the feature [-tense] is activated as the enhancement of the AP-initial L tone with relatively short VOT primarily parsed for cues to the feature [-s.g.], as in (5a ii).Therefore, word-initial Japanese voiced plosives are categorized as lenis ([-s.g., -tense]).17 As for the Seoul subjects' categorization of word-medial voiced and voiceless Japanese plosives as lenis and as either aspirated or fortis, respectively, with no tonal effect, we suggest that it is the difference in closure duration that is parsed for cues to the feature [±tense], as in (5b).Long closure duration of word-medial Japanese voiceless plosives is parsed for cues to the Korean laryngeal feature [+tense], and therefore, the voiceless plosives are categorized as either aspirated or fortis ([+tense]), as in (5b i).Short closure duration of word-medial Japanese voiced plosives is parsed for cues to [-tense], as in (5b ii), resulting in their adaptation of the Japanese plosives as lenis. (5) Seoul subjects' categorization of Japanese voiceless and voiced plosives (a) in word-initial and (b) in word-medial position.Japanese (L2) cues Korean (L1) a. i. [-voice] ↔ long VOT with the enhancementof AP-initial H ([+tense]) Second, recall that, like the Seoul subjects, the Kyungsang subjects had better categorization of the word-initial Japanese voiceless plosives as aspirated at each level of syllable length when a tone in a following vowel is H, as shown in Figure 5(b), and word-medial Japanese voiced and voiceless plosives as lenis and as either aspirated or fortis with no tonal effect, respectively, as in Figures 7(b) and 9(b).Therefore, we suggest that the Kyungsang subjects' categorization of word-initial Japanese voiceless plosives and wordmedial Japanese plosives can be accounted for in the same way to the Seoul subjects', as in (5a i) and (5b), respectively.Unlike the Seoul subjects, however, the Kyungsang subjects favored H though they categorized word-initial Japanese voiced plosives as lenis like the Seoul subjects.As for the different tonal effects between the Kyungsang and the Seoul subjects' categorization of word-initial Japanese voiced we may leave them for further research, because there has been no research of tonal effect on native Korean or loan words of different syllable length in the two dialects in the literature.Therefore, we tentatively suggest that short VOT is primarily parsed for cues to the feature [-s.g.] with the feature [-tense] by default in the Kyungsang subjects' categorization of word-initial Japanese voiced plosives as lenis.
Before closing this section, we may note that the Seoul and Kyungsang subjects' categorization of the word-initial Japanese voiceless plosives [k, t] as the aspirated /k h , t h / is of interest in that it is different from the regulations on the Korean adaptation of the word-initial Japanese voiced and voiceless plosives as lenis by the National Institute of the Korean Language (NIKL) (2012).When Japanese words beginning with voiced and voiceless plosives are borrowed and lexicalized in current Korean, the word-initial voicing contrast of the source language is constrained to be neutralized, no matter whether the word-initial plosives are followed by a H or L vowel, as shown in the lexical representations of some Korean adapted forms with word-initial plosives in bold in (6).( 6 The discrepancy between the present results and the NIKL regulations indicates that the regulations, that is, spelling conventions made by NIKL, do not affect our subjects' categorization of Japanese words at all. 18Recall that we selected real Japanese words which are not familiar at all to Koreans in order to avoid any spelling convention of Japanese loans frequently used in Korea.To be specific, we assume that our Seoul subjects were faith-ful to the phonetic difference in VOT and in AP-initial L vs. H between the word-initial Japanese voiced and voiceless plosives when given Japanese words which are not lexicalized in Korean.Thus, the acoustic cues are parsed to the features [±tense] and [±s.g.] with the former as an AP-initial enhancement, as in (5a), rather than to the NIKL regulations. 19nother example wherein spelling conventions do not affect our subjects' adaptation of Japanese words comes from their categorization of word-medial Japanese voiceless plosives.According to the NIKL regulations, we are advised to use aspirated plosives for word-medial Japanese voiceless plosives.However, an almost equal distribution of fortis and aspirated plosives was found in both the Seoul and Kyungsang subjects' responses for the Japanese voiceless plosives [k, t] in intervocalic position as a free alternation, which is shown in Figure 8(b) and (c).

Theoretical implications
Some theoretical implications can be made in this section.
First, the present study is the first in examining a cross-dialect difference in the magnitude of H/L tonal effects and segmental voicing contrast in Korean categorization of Japanese plosives followed by a H or L vowel, using two-, three-and four-syllable Japanese words.In the literature on AP-initial tones in accordance with the three-way phonation contrast in plosives, there has been no study which explicitly examines any cross-dialect differences in Korean.So far AP-initial tones have been investigated in the Seoul and Chonnam dialects (e.g.Jun 1993) and in Kyungsang Korean (e.g.Kenstowicz & Park 2006).In addition, there has been no research on how H/L tonal effects and segmental voicing contrast do interact in Korean categorization of Japanese plosives folllowed by a H or L vowel.In this aspect, the present study could be considered as the first attempt to examine a crossdialect difference in the interaction of Japanese H/L tonal effects and segmental voicing contrast between Seoul and Kyungsang Korean.
Second, the H and L tonal distinction in AP-initial position in the Seoul subjects' categorization of Japanese plosives indicates that it is not specified in the lexical representation of Korean consonants even among young Seoul Koreans.Recently, Silva (2006) has proposed that lenis plosives are specified as [+s.g.] like aspirated plosives and that H and L are underlyingly specified for aspirated and lenis plosives, respectively, in contemporary Seoul Korean.This is because his three young Korean subjects, who were born after 1982, do not have any difference in VOT between word-initial lenis and aspirated plosives.However, it is noteworthy that among the subjects (80 male and 80 female) in the present study, one hundred forty-seven of them were born between 1985 and 1992 with nine between 1982-1984 and five in 1981.If the tonal distinction were lexically specified in distinguishing lenis from aspirated plosives with no phonological function of the feature [s.g.], then our young Seoul subjects would have perceived the word-initial Japanese voiceless plosives as either aspirated or fortis, in that fortis consonants are also assumed to have H tones like aspirated consonants.But this is not the case.
In addition, the lexical specification of the H and L distinction cannot account for sound patterns, either.Korean, including not only Seoul Korean but also Kyungsang Korean, changes some word-initial lenis consonants into their fortis counterparts in order to convey speakers' intensified feelings, as shown in (7a). 20No aspirated counterparts occur.The alternation of lenis consonants with fortis counterparts does also occur to the exclusion of aspirated ones in Kyungsang Korean, as in Seoul Korean.For example, as shown in (7b), North Kyungsang Korean also replaces lenis consonants with fortis counterparts in wordinitial position, regardless of whether a following vowel is H or L. 21,22   (7) Word-initial lenis stops in (i) non-intensified expressions and fortis stops in (ii) intensified expression in (a) native Korean words (H.Kim 2003;2005;2011)  Moreover, according to Kim et al. (2018), glottal opening peak, airflow peak height, duration of aspiration and VOT of word-medial lenis plosives are significantly reduced, as compared to those in word-initial lenis plosives, in their four subjects of Seoul Korean.
In contrast, aspirated and fortis plosives have no statistical difference in them across the contexts.The significant difference in the phonetic properties between word-initial and word-medial lenis plosives is proposed to be due to their laxness ([-tense]), and it is due to the tenseness ([+tense]) of aspirated and fortis plosives that there is no difference in them.
Third, the activation of the Korean prosodic unit of AP as enhancement and laryngeal features [±tense] and [±s.g.] in (5) supports the view that L2 acoustic outputs are computed by an L1 grammar (e.g.Polivanov 1931;1974;Trubetzkoy 1939;Hyman 1970;Peperkamp 2005;Yip 2006).So far previous studies on the prosodic unit have focused on native or nonsense word segmentation in Korean (e.g.Jun 1993;1998;2005a;b;Jun & Kim 2004;S. Kim 2004).In this aspect, the tonal effect in AP-initial position in the Seoul subjects' categorization of word-initial Japanese plosives provides a case where the prosodic unit of AP is also psychologically real in loanword adaptation, as in native word segmentation.In addition, recently, based on the Korean adaptation of English, French and Japanese voiced and voiceless consonants, H. Kim (2006;2007;2008;2009;2014;2017a) has suggested that L1 grammar such as L1 distinctive features, syllable structure and lexical restrictions plays a role in the adaptation of L2 sounds.The present study further supports the view of an L1 grammar-driven perception of L2 sounds, in that Korean AP-initial boundary tones as well as Korean laryngeal features are employed in the Seoul subjects' categorization of Japanese plosives followed by a H or L vowel.
The other two linguistically-motivated views on loanword adaptation in the literature -(a) the phonological view and (b) the phonetic approximation view -would be hard to account for the results of the present perception experiment.If loanword adaptation is based on phonological category mappings between the L2 and L1 languages (e.g.Paradis & LaCharité 1997;LaCharité & Paradis 2005;Paradis & Tremblay 2009), the H/L tonal distinction in Japanese test words would be borrowed across the contexts by Kyungsang subjects whose dialect has a lexical pitch-accent like Japanese.Yet, this is not the case, as shown in Figures 7 and 9.
The role of the tonal distinction in word-initial position in the Seoul subjects' categorization (5a) would not be accounted for either in the phonetic approximation view wherein L1 speakers perceive and produce the native segment which most closely approximates the L2 input in articulatory and/or acoustic properties, when confronted with an L2 sound (e.g.Silverman 1992;Steriade 2001;Kenstowicz 2003;Kang 2003;Peperkamp & Dupoux 2003).In this view, the tonal distinction only in word-initial Japanese plosives by the Seoul subjects would not be expected in that the phonetic difference in H and L after Japanese plosives is made in the Japanese acoustic outputs in both word-initial and wordmedial positions. 23

Conclusion
In the present study, we have found that our Seoul and Kyungsang subjects mostly categorized word-initial Japanese voiceless plosives as aspirated with the significant effect of H and word-medial voiceless plosives as either aspirated or fortis with no H/L effect.Their categorization of word-medial Japanese voiced plosives as lenis is not significantly affected by the H and L tonal difference, either, regardless of dialect differences.In their categorization of word-initial Japanese voiced plosives as lenis, however, the Seoul subjects favored L, and the Kyungsang subjects H.
Based on these results, we have proposed that the Korean prosodic unit of AP and laryngeal features interact in the Seoul subjects' categorization of word-initial Japanese plosives, such that the H/L tonal distinction is made in AP-initial position as enhancement with VOT primarily parsed for cues to the feature [±s.g.].Regarding their categorization of word-medial Japanese plosives with no tonal effect, we have proposed that closure duration is parsed for cues to the other laryngeal feature [±tense].The same proposal is made for the Kyungsang subjects' categorization except for the H effect in word-initial Japanese voiced plosives which needs further research.
The effect of L1 (i.e.Korean) AP-initial boundary tones as enhancement in the Seoul subjects' categorization suggests that the prosodic unit of AP is also psychologically real in loanword adaptation, as in native word segmentation, and that the H/L tonal distinction is not underlyingly specified in aspirated and lenis plosives across the contexts in current Seoul Korean.In addition, not only the activation of the L1 AP-initial boundary tones but also that of L1 laryngeal features [±tense] and [±s.g.] supports the view that L2 acoustic ouputs are computed by L1 grammar in the literature.As the first cross-dialect study on the interaction of H/L tonal effects and segmental voicing contrast in Korean categorization of Japanese plosives followed by a H or L vowel, the present study leaves, in the future, further relevant research such as the tonal effects in Seoul and Kyungsang subjects' perception of native Korean or loan words in different syllable lengths for a supplement to the present study. 23In addition, the average 16ms VOT of word-initial Japanese voiced plosives and 47 ms VOT of Japanese voiceless plosives in Table 5(a) would acoustically approximate Korean fortis and lenis plosives, respectively, given that the average VOT of fortis plosives is 25 ms, that of lenis plosives 33 ms and that of aspirated plosives 105 ms in word-initial position (Lisker & Abramson 1964).But this is not the case, as in Figures 2 and 4.Moreover, the long closure duration and 19 ms VOT of word-medial Japanese voiceless plosives (Table 5b) would phonetically approximate Korean fortis plosives.This is because the average VOT is 13 ms for fortis, 26 ms for lenis and 82 ms for aspirated plosives in word-medial position with the closure duration of fortis and aspirated plosives longer than lenis (e.g.Lisker & Abramson 1964;C.-W. Kim 1965) (See also Kim et al. 2018 for duration of aspiration as well as VOT and closure duration of the three-way phonation contrast in Korean plosives).Yet, the Japanese plosives were categoraized as either aspirated or fortis plosives as a free alternation, as in Figure 8.

Figure 1 :
Figure 1: The alignment of F0 movements in the Japanese word katagami with (a) its original LHHH pitch and (b) a HLLL F0 manipulation.

Figure 2 :
Figure 2: The overall percentage of Seoul and Kyungsang subjects' categorization of word-initial Japanese voiced plosives as lenis when a following vowel is H or L.
of word-initial Japanese voiced plosives as lenis Seoul subjects

Figure 3 :
Figure 3: The probability of (a) Seoul and (b) Kyungsang subjects' categorization of word-initialJapanese voiced plosives as lenis when a following vowel is H or L.

Figure 4 :
Figure 4: The overall percentage of Seoul and Kyungsang subjects' categorization of word-initial Japanese voiceless plosives as aspirated when a following vowel is H or L.

Figure 5 :
Figure 5: The probability of (a) Seoul and (b) Kyungsang subjects' categorization of word-initial Japanese voiceless plosives as aspirated when a following vowel is H or L.

Figure 6 :
Figure 6: The overall percentage of Seoul and Kyungsang subjects' categorization of word-medial Japanese voiced plosives as lenis when a following vowel is H or L.
of word-medial Japanese voiced plosives as lenis Seoul subjects

Figure 7 :
Figure 7: The probability of (a) Seoul and (b) Kyungsang subjects' categorization of word-medialJapanese voiced plosives as lenis when a following vowel is H or L.

Figure 8 :
Figure 8: The overall percentage of (a) Seoul and Kyungsang subjects' categorization, (b) Seoul and (c) Kyungsang subjects' categorization of word-medial Japanese voiceless plosives as either aspirated or fortis when a following vowel is H or L.

Figure 9 :
Figure 9: The probability of (a) Seoul and (b) Kyungsang subjects' categorization of word-medialJapanese voiceless plosives as either aspirated or fortis plosives when a following vowel is H or L.

Table 1 :
The statistical results of (a) Dialect(Seoul, KS), H/L and the interaction of Dialect and H/L in Seoul and Kyungsang (KS) subjects' responses as lenis for the word-initial Japanese voiced plosives [b, d, g], (b) Seoul and (c) Kyungsang subjects' responses for H/L, Syllable and the interaction of H/L and Syllable.

Table 2 :
The statistical results of (a) Dialect(Seoul, KS), H/L and the interaction of Dialect and H/L in Seoul and Kyungsang (KS) subjects' responses as aspirated for the word-initial Japanese voiceless plosives [k, t], (b) Seoul and (c) Kyungsang subjects' responses for H/L, Syllable and the interaction of H/L and Syllable. a.

Table 3 :
The statistical results of (a) Dialect(Seoul, KS), H/L and the interaction of Dialect and H/L in Seoul and Kyungsang (KS) subjects' responses as lenis for the word-medial Japanese voiced plosives [b, d, g], (b) Seoul and (c) Kyungsang subjects' responses for H/L, Syllable and the interaction of H/L and Syllable. a.

Table 4 :
The statistical results of (a) Dialect(Seoul, KS), H/L and the interaction of Dialect and H/L in Seoul and Kyungsang (KS) subjects' responses as either aspirated or fortis for the wordmedial Japanese voiceless plosives [k, t], (a) Seoul and (b) Kyungsang subjects' responses for H/L, Syllable and the interaction of H/L and Syllable. a.

Table 5 :
The average of closure duration and VOT with standard deviations in parentheses in our Japanese test words (a) word-initially and (b) word-medially (unit: ms).Kim: The effects of L1 AP-initial boundary tones and laryngeal features in Korean adaptation of Japanese plosives followed by a H or L vowel Art.49, page 21 of 31 lenis and fortis plosives as[-s.g.], as in (4a).The acoustic property of closure duration is accounted for by the feature [±tense], that is, long closure duration in aspirated and fortis stops by [+tense], and short closure duration in lenis ones by [-tense], as in (4b).16