国立国語研究所学術情報リポジトリ
日本語ダウンステップの再検討 : 形態の影響
メタデータ

言語: English
出版者:
公開日: 2021-07-16
キーワード (Ja):
キーワード (En): lexical category, production test,
downstep, Japanese
作成者: ホワン, ヒョンギョン, 平山, 真奈美, HWANG,
Hyun Kyung, HIRAYAMA, Manami
メールアドレス:所属:

URL

https://doi.org/10.15084/00003434

国立国語研究所論集 (NINJAL Research Papers) 21: 15–23 (2021)
ISSN 2186-1358

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Downstep in Japanese Revisited: Morphology Matters
HWANG Hyun Kyunga   HIRAYAMA Manamib
aUniversity of Tsukuba /Adjunct Researcher, Theory & Typology Division, Research Department, NINJAL [–2017.03] /Project Collaborator, NINJAL
bSeikei University
Abstract
It has been widely acknowledged that an f0 after an accented word is noticeably lower thanafter an unaccented word in Japanese (i.e., downstep). In pursuing research concerning thesyntax-phonology interface, Selkirk and Tateishi (1991) highlight the lack of downstep at theleft edges of maximal projections of syntactic categories (XPs), and propose that the left edgesof XPs are mapped onto the left edges of the major phrase boundaries that block downstep.
Kubozono (1991) provides empirical results that are different from Selkirk and Tateishi (1991).
This study aims to test the effect of different lexical categories on downstep, as the distinction
between different categories is frequently ignored in the literature regarding Japanese downstep.
The results from a production test suggest the possibility that distinct lexical categories
influence the presence or absence of downstep in Japanese. Specifically, downstep occurred in thenoun condition but not in the adjective condition with -i endings, which casts doubt on Selkirk
and Tateishi’s generalization. We propose that the blocking of downstep is due to the perceived
unnaturalness associated with the morphology of adjectives. Moreover, this research reveals an
important implication regarding the methodology: lexical category and morphological forms
should be carefully controlled for studying Japanese downstep.*
Keywords: lexical category, production test, downstep, Japanese

1. Introduction
It has been widely acknowledged that the fundamental frequency (henceforth f0) peak of thematerial following an accented word is noticeably lower than that following an unaccented wordin Japanese (Poser 1984, Pierrehumbert and Beckman 1988, Kubozono 1989, among others).
This f0 lowering effect triggered by a preceding accented item is referred to as downstep. In pursuing research concerning the syntax-phonology interface, Selkirk and Tateishi (1991) highlightthe lack of downstep at the left edges of maximal projections of syntactic categories (henceforthXPs), and propose that the left edges of XPs are mapped onto the left edges of the major phraseboundaries that block downstep. More interestingly, they compare two lexical categories: adjectives (A) and nouns (N) ([A1 [A2 N]] vs. [N1 [N2 N3]]), and report that downstep occurs only in
A2, not in N2. Based on this observation, Selkirk and Tateishi claim that N2 is at the left edge ofa maximal projection NP, whereas [A2 N] does not constitute a maximal projection.
* We would like to thank the audience at LabPhon 15 and Haruo Kubozono for their valuable comments.
The work reported in this article was partially supported by the NINJAL collaborative research project‘Cross-linguistic Studies of Japanese Prosody and Grammar’ (project leader: Haruo Kubozono) and JSPS
KAKENHI grant #19K00613.

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HWANG Hyun Kyung・HIRAYAMA Manami / NINJAL Research Papers 21: 15–23 (2021)

Methodologically, Selkirk and Tateishi’s diagnosis is rather syntagmatic because the mean
f0s of two adjacent phrases are compared within a single utterance. As displayed in the schematic
f0 curves (1), the presence of downstep is determined within a sentence. Apostrophes indicate
lexical pitch accents. For instance, in a phrase shiro’i naga’i mame’ ‘long white beans (literally,
white long bean(s))’, where there are two accented phrases shiro’i and naga’i in a row, and thus
the first accented phrase shiro’i potentially triggers the second phrase naga’i to be downstepped,
the second accented phrase naga’i is considered downstepped if the pitch is lower in this phrase
when compared to the preceding phrase.
(1) Schematic pitch curves in syntagmatic downstep
Accented
shiro’i

Accentednaga’imame’

Traditionally, however, the presence or absence of downstep has been tested paradigmatically by comparing the f0 peaks of targets following accented and unaccented words. In theparadigmatic description of downstep in Japanese (e.g., Poser 1984, Kubozono 1989, Kubozono2007), the presence of downstep is diagnosed by comparing f0 curves in two sentences/phrases.
For example, the naga’i phrase in shiro’i naga’i mame’ ‘white long beans’ is considered downstepped if the f0 peak in this phrase is lower when compared to an equivalent phrase fromanother sentence that has the same structure except that the preceding phrase is unaccented, e.g.,amai naga’i mame’ ‘long sweet beans’, where the first phrase amai is unaccented. This is illustratedin (2). Whether or not the phrase naga’i is downstepped can be diagnosed only by comparing
the f0 peak in that phrase with the f0 peak in the second phrase in (b), in which it must not be
downstepped due to the preceding unaccented phrase. The phrase naga’i is downstepped in (2a)if its pitch is lower than the pitch in naga’i in (2b).
(2) Schematic pitch curves in the paradigmatic downstep(a) Accented
shiro’i(b) Unaccented
amai

Accentednaga’imame’

Accentednaga’imame’

It is not a trivial issue to diagnose the presence or absence of downstep using the syntagmatic diagnostic since it is not obvious how much f0 lowering is necessary as an indication ofdownstep. Thus, we mainly adopt the paradigmatic diagnostic in this study, although the syntagmatic diagnostic has been used in much of the literature on Japanese downstep (Selkirk andTateishi 1991, Nagahara 1994, Hirotani 2005).
Regardless of the methodology, the distinction between different categories is frequently
ignored in the literature on Japanese downstep. One tested pair from Kubozono (1989) is givenin (3). In (3a), the trigger ao’i is an adjective, while the target momen is a noun. Further, the target
marui in the utterance for comparison (3b) is an adjective, which is a different category from that

HWANG Hyun Kyunga・HIRAYAMA Manami / NINJAL Research Papers 21: 15–23 (2021)

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in (3a).
(3) A test set in Kubozono (1989)
a. ao’i		 momen-no ori’mono			 blue cotton-gen fabric			 ‘blue cotton fabric’b. amai marui me’ron			 sweet round melon			 ‘sweet round melon’
Kubozono (1991) investigated two speakers with more controlled phrases, in particular [N [NN]] (a’ni-no men’no eri’maki ‘(my) brother’s cotton muffler’) and [A [A N]] (ao’i o’okina eri’maki ‘ablue, big muffler’), both of which showed downstep (see section 4 for more discussion). Selkirk
and Tateishi (1991) mention that Adjective Phrase (AP) boundaries do not block downstep
unlike Noun Phrase (NP). Thus, the literature does not agree on the presence or absence ofdownstep in a particular category. Testing the effect of different lexical categories on downstep
is an important line of research, and a more strictly controlled paradigmatic investigation with alarger set of data is needed to confirm the probable influence of lexical categories. In the current
study, we investigate the effect of lexical categories, particularly N and A, paradigmatically. The
results indicate that these two conditions influence downstep differently in Japanese. In addition,
it implies that a new approach that is capable of accounting for a fuller range of data is necessary.
2. Methods
To investigate whether there is a difference in the downstep patterns depending on the lexical
categories, particularly in phrases involving adjectives and those involving nouns, a production
experiment was conducted. This section describes the design and data used in the experiment.
2.1 Material
In each of the A and N conditions, two phrases with accented triggers and two phrases withunaccented “triggers” were compared. In examples (4) and (5), (4) involves adjectival modifiers,and (5) involves nominal modifiers. In both (4) and (5), sentences in (a) and (b) have the samephonological lengths (counted by mora) and right-branching structure [X [X X]]. The mora is aphonological unit in Japanese, and (C)V and coda consonants are counted as one mora (see, forexample, Kubozono 1999, for the mora in Japanese). In the adjectival modifier condition, as in(4), a noun phrase containing two adjectives modifies the head noun [A1 [A2 N]], for example,
shiro’i naga’i mame’ ‘long white beans’ (literally ‘white long bean(s)’) (4a). Sentences (4a) and (4b)differ in terms of accentuation on A1, which is the trigger of downstep. In (4a), the trigger (shiro’i) is accented, while it (amai) is unaccented in (4b). The f0s of targets are compared to investigate paradigmatic downstep. A lower f0 in the target with an accented trigger (naga’i in (4a))
than in the target with an unaccented trigger (naga’i in (4b)) is the indication of the presence ofdownstep.

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HWANG Hyun Kyung・HIRAYAMA Manami / NINJAL Research Papers 21: 15–23 (2021)(4) Adjectival modifiers									Trigger		Target		Head N
a. a’ni-wa			shiro’i		naga’i		mame’-o		utta.
			 brother-top white		long			bean-acc		 sell.past			 ‘My brother sold long white beans.’
b. a’ni-wa			amai			naga’i		mame’-o		utta.
			 brother-top sweet		long			bean-acc		 sell.past			 ‘My brother sold long sweet beans.’
In the phrases with nominal modifiers [N1 [N2 N]], as in (5), two nouns, N1 and N2, modify
the head noun, for example, no’mo-no na’ra-no mame’ ‘Nomo’s beans from Nara’ (literally ‘Nomo’s
Nara’s bean(s)’). The particle -no that attaches to a noun represents the modification relation
between nouns. Once more, (5a) and (5b) differ in terms of whether the trigger is accented (5a)or unaccented (5b). The two modifying nouns (N1 and N2) are proper nouns, with N1 being
either a surname or a given name and N2 being Nara, a city name. Proper nouns were usedbecause common nouns were difficult to find to control for experimental factors, including thesegmental structure, number of moras, and accentuation.
(5) Nominal modifiers									Trigger			Target			 Head N
a. a’ni-wa			no’mo-no		na’ra-no		mame’-o		utta.
			 brother-top Nomo-gen Nara-gen bean-acc		 sell.past			 ‘My brother sold Nomo’s beans from Nara.’
b. a’ni-wa			ono-no			na’ra-no		mame’-o		utta.
			 brother-top Ono-gen		 Nara-gen bean-acc		 sell.past			 ‘My brother sold Ono’s beans from Nara.’
There were two phrases for each of the types in (4) and (5) in the experiment. Therefore, atotal of eight phrases were tested.1
2.2 Recording and measurements
The [A1 [A2 N]] and [N1 [N2 N]] phrases discussed in Section 2.1 were put in a carrier phrasea’ni-wa __ -o utta ‘my brother sold ___’. The sentences were divided into two lists so that eachlist contained one item of a pair of accented and unaccented sentences. Each list had 18 randomized distractor sentences; these other sentences were for other projects and are not discussed
1 The other test sentences are given below.
1. Adjectival modifiers [A1 [A2 N]]
a. a’ni-wa				 uma’i naga’i mame’-o		 utta.		 ‘My brother sold long delicious beans.’brother-top		good long		bean-acc		 sell.past
b. a’ni-wa				 marui naga’i mame’-o		 utta.		 ‘My brother sold long round beans.’brother-top		round long		bean-acc		 sell.past
2. Nominal modifiers [N1 [N2 N]]
a. a’ni-wa			 ma’mi-no		 na’ra-no		 mame’-o		 utta.	 ‘My brother sold Mami’s beans from Nara.’brother-top Mami-gen Nara-gen bean-acc		 sell.past
b. a’ni-wa			 yano-no		 na’ra-no		 mame’-o		 utta.	 ‘My brother sold Yano’s beans from Nara.’brother-top Yano-gen Nara-gen bean-acc		 sell.past

HWANG Hyun Kyunga・HIRAYAMA Manami / NINJAL Research Papers 21: 15–23 (2021)

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in this paper. Six speakers from Tokyo or nearby areas participated in the study (two males andfour females, mean age 30.3, range 24–33). They repeated the two lists eight times. Thus, there
were 384 tokens recorded in total. The recording was performed in a room with sound-attenuating walls. We used a Marantz PMD661 recorder with a sampling rate of 44.1 kHz and 24-bit
quantization, and a unidirectional dynamic microphone (SHURE SM10A, frequency response:
50–15,000 Hz).
We measured peak f0 of each of the phrases in [A1 [A2 N]] and [N1 [N2 N]] plus the subject/topic phrase a’ni-wa as the reference point, as illustrated in (6), in which the boundaries aremarked with a vertical bar (|). The f0 measurements were performed by using Praat and runninga script called ProsodyPro (Xu 2013) on the intervals made manually. A screenshot indicating theintervals (numbered 1 to 4 for the phrases) is presented in Figure 1. We measured the peak f0s sothat our work is comparable with the data in the literature where the paradigmatic diagnosis was
utilized (Kubozono 1989, 1991).
(6) Peak f0s in four intervals
		Reference			Trigger				Target			Head N
a. | a’ni-wa			| shiro’i			| naga’i			| mame’ | -o		utta.
			 brother-top white				long				bean-acc 		sell.past			 ‘My brother sold long white beans.’b. | a’ni-wa			 | no’mo-no		 | na’ra-no		 | mame’ | -o		 utta.
			 brother-top Nomo-gen Nara-gen bean-acc			sell.past			 ‘My brother sold Nomo’s beans from Nara.’

Pitch (Hz)

400

1
0

0

2

3
Time (s)4
2.164

Figure 1 The spectrogram and pitch contour of (6a) a’niwa shiro’i naga’i mame’o utta uttered by Speaker RA, withintervals indicating the reference phrase (1), the trigger phrase (2), the target phrase (3) and the head noun (4).

For statistical analyses, linear mixed-effects models were used. The speaker and item were enteredinto the model as random effects; random intercepts and random slopes were included for the
speaker and random intercepts were included for the item (Barr et al. 2013). Linear mixed-effects analysis with R (R Core Team 2014) was performed on the relation between the peak f0s of

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the target XPs and the accentedness of the trigger XP (i.e., accented vs. unaccented).
3. Results
The influence of accentedness (A vs. U) on downstep differed between NP and AP. Figure 2 displays the average peak f0s of the four conditions: 2 categories (NP/AP) × 2 accentedness (A/U).
As for N (right), the peak f0s of the targets in the unaccented condition (NP_U; dotted line)
were remarkably higher than those in the accented counterparts (NP_A; solid line), suggestingthat the targets were downstepped. As for A (left), on the other hand, no such difference wasfound in the target between accented (AP_A; solid line) and unaccented (AP_U; dotted line)
conditions; the difference is quite minimal.

Figure 2 Average peak f0s of the four phrases in the AP (left) and NP (right) conditions

These observations were confirmed in the statistical analyses, where A and N did indeed
differ in terms of the effect of accentedness. The f0s of the targets between the accented andunaccented tokens for A and N were compared individually, thereby revealing that the unaccented targets (AP_U & NP_U) yielded quite different F0s depending on their lexical category(see Figure 2). In N, there was a significant effect of the accent (Table 1). The peak f0 of thetarget phrase is higher in phrases where the trigger is unaccented than in phrases where the trigger is accented. As indicated in Table 1, the model estimates it to be higher by 19.936 Hz. Thisdifference was statistically significant (t = 4.934, p = 0.003742). Hence, downstep occurred in the
N condition.
Table 1 Results of the statistical analysis for NP

Factorβ-coefﬁcient

Trigger unaccented

19.936

Intercept

219.646

t

p

4.934

0.003742 **10.6340.000119 ***In contrast, there was no effect of the accent in the results involving A (Table 2). The accentdifference on the trigger AP does not have a significant effect on the f0 of the target AP (t =1.143, p = 0.304720), indicating that downstep did not occur in this condition.
Table 2 Results of the statistical analysis for AP
Factorβ-coefﬁcient

Trigger unaccented

4.911

Intercept

220.285

t

p

1.143

0.304720

10.4900.000136 ***HWANG Hyun Kyunga・HIRAYAMA Manami / NINJAL Research Papers 21: 15–23 (2021)

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4. Discussion and conclusions
The current study explored the influence of the parts of speech in the presence or absence ofdownstep in Japanese. Specifically, we compared [N1 [N2 N]] and [A1 [A2 N]] to examine
whether N2 and A2 undergo downstep given the accented triggers N1 and A1, respectively. The
results of a production study suggest that distinct lexical categories make a significant differencein terms of downstep: downstep was observed at N2 in [N1 [N2 N]] (which replicates Kubozono’s(1991) results in a comparable structure), whereas it was blocked at A2 in [A1 [A2 N]].
The results with adjectives appear to contradict those in Kubozono’s (1991) results, where
downstep was observed in the phrase [ao’i [o’okina eri’maki]] ‘a blue, big muffler’. It is possiblethat the seemingly contradictory results can simply be attributed to the speaker/age difference.
However, there may not be any contradiction between the two studies if we carefully consider thetest phrases and the morphology of the words in those phrases.
In fact, the consideration suggests two possible analyses of the results with respect to the
influence on downstep. In Japanese morphology, the words used in the adjective condition inthis study (shiro’i, naga’i, uma’i, marui, amai) are usually analyzed as adjectives while ookina ‘big’
may allow more than one analysis. One possible category it belongs to is rentaishi (e.g., Masuoka
and Takubo 1992: 55). O’okina also displays some properties common to adjectival nouns (kei­youdoushi) (Kageyama 1993: 25). Thus, if we assume that o’okina is not in the same lexical category as words used in this study, the different results between this study and Kubozono’s (1991)
can mean that different lexical categories affect the presence and absence of downstep. Stillanother possibility for o’okina in terms of its part of speech is that it is a form of adjective (p.c.
Haruo Kubozono). If we assume this, then the different results between the two studies can besaid to show that different morphological forms within the category (here adjective) may affectdownstep: the -i form of the adjective blocks downstep, whereas the -na form does not.
What does the morphological distinction mean linguistically with respect to the presence
and absence of downstep? The difference between N and A may be attributed to the syntactic
characteristics that are exhibited by each category, particularly A. That is, what matters is probably not the lexical category per se, but the different usages of adjectives—attributive vs. predicative. In fact, Kuno (1973) separates the two usages and considers the attributive use as a relative
clause. However, Hirayama and Hwang (2019) and Hirayama, Hwang, and Kato (2019) findthat the left edge of relative clauses does not block downstep, which does not support this line of
explanation if we analyze the attributive use of an adjective as a relative clause.
Alternatively, perceived naturalness may account for the different patterns between the morphological differences. For example, a noun phrase that has two adjectives with -i ending individually modifying the head noun ([A-i1 [A-i2 N]]), as in (2a) [shiroi [nagai mame]] ‘long whitebeans’, does not sound quite natural, though not ungrammatical, in Japanese. We propose that
because of this unnaturalness, speakers tend to insert a prosodic phrase boundary between the
two adjectives, which results in a pitch reset by blocking downstep. Indeed, the structure where
the first adjective appears in the -te (or gerundive) form (i.e., [[A-te A] N]) sounds more natural(e.g., [[shiroku-te nagai] mame] ‘white and long beans’) when two adjectives are used to modify anoun. Similarly, when the second word is o’okina with -na in the end, as in phrases by Kubozono(1991), the phrase does not sound unnatural at all. In addition, phrases in the N condition [N-no[N-no N]] (Kubozono 1991, this study) do not give rise to any perceived unnaturalness when
Japanese speakers parse them.

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HWANG Hyun Kyung・HIRAYAMA Manami / NINJAL Research Papers 21: 15–23 (2021)

Furthermore, the empirical results provided in the current study appear to contradict thosereported by Selkirk and Tateishi (1991). In particular, the occurrence of downstep in the N
condition corroborates the argument by Kubozono (1988, 1989, 1991) and Pierrehumbert andBeckman (1988), which casts doubt on Selkirk and Tateishi’s generalizations concerning thesyntax-phonology interface. As mentioned earlier, they argue that major phrase boundaries inJapanese are inserted at the left edges of XPs. Given this generalization, a pitch reset rather thana downstep is expected in the structure [N1 [N2 N]]. One source of the discrepancy may be dueto the different methodologies: downstep was diagnosed based on the syntagmatic analysis by
Selkirk and Tateishi (1991). On the other hand, the paradigmatic analysis in this study and by
Kubozono (1991) found that NP did not block downstep, suggesting that a new approach is necessary that is capable of accounting for a fuller range of data.
Moreover, this research has an important implication regarding the methodology ofJapanese phonology. In testing downstep, sentences are commonly used without considering different lexical categories or different morphological forms. However, these results indicate that f0s
are affected by the morphology of materials, suggesting that the morphological category should
be carefully controlled in the study of Japanese downstep.
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Hirayama, Manami and Hyun Kyung Hwang (2019) Relative clause and downstep in Japanese. In: Katherine Hout, Anna Mai, Adam McCollum, Sharon Rose and Matt Zaslansky (eds.), Supplemental Proceedings of the 2018 Annual Meeting on Phonology. (https://doi.org/10.3765/amp.v7i0.4466). Washington,
DC: Linguistic Society of America.
Hirayama, Manami, Hyun Kyung Hwang and Takaomi Kato (2019) Lexical category in downstep in Japanese. In: Sasha Calhoun, Paola Escudero, Marija Tabain and Paul Warren (eds.) Proceedings of the 19thInternational Congress of Phonetic Sciences, 2851–2855.
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University of Massachusetts.
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日本語ダウンステップの再検討――形態の影響――

ホワン ヒョンギョン a

平山真奈美 ba 筑波大学／国立国語研究所 研究系 理論・対照研究領域 非常勤研究員［–2017.03］／
国立国語研究所 共同研究員
b 成蹊大学要旨
日本語には，無アクセント語に後続する語の f0 よりアクセントのある語に後続する語の f0 が低くなる現象，いわゆるダウンステップがある。統語と音韻のインターフェースの観点から，
Selkirk and Tateishi（1991）は，XP の左端が major phrase の左端に写像され，これによりダウンス
テップがブロックされると主張する。しかし Kubozono（1991）のデータはこの主張に反する。
本研究では，従来の研究で特に取り沙汰されていなかったダウンステップにおける品詞の影響を検討した。
音声産出実験の結果，品詞が日本語のダウンステップの有無に影響する可能性があることが明らかになった。特に，名詞の連続する句でダウンステップが見られたが，形容詞のイ形が連続する句では見られなかった。先行研究の指摘同様，Selkirk and Tateishi（1991）の一般化には疑問が残る。ダウンステップが阻止される要因は，ある形態を使用するときに生まれる句全体の不自然さであると分析した。また，日本語のダウンステップ研究で形態をコントロールする必要がある
ことが示唆された。
キーワード：品詞，音声産出，ダウンステップ，日本語