Syntactic Priming Effects on the Processing of Japanese ... - J-Stage

Cognitive Studies, 14(2), 173-191. (June 2007)

● Research Paper ●

Syntactic Priming Effects on the Processing of Japanese  Sentences with Canonical and Scrambled Word Orders Jun-Ichi Tanaka1,2 , Katsuo Tamaoka3 , and Hiromu Sakai1   The present study conducted two experiments to examine the effects of syntactic priming in sentence comprehension, using a cross-modal priming task which required participants to make acceptability judgment of Japanese sentences with canonical and scrambled word orders. Experiment 1 investigated whether or not the speed of target sentence processing would be affected by the syntactic structure of prime sentences. Prime sentences matching target sentences in word order facilitated processing of target sentences even though prime-target pairs shared no content words, while prime-target pairs with mismatched word orders demonstrated weak facilitation effects. Experiment 2 examined the processing speed of target sentences primed by a sequence of nouns without any syntactic structure. The weak priming effects disappeared in the noun prime condition, which suggested that those observed in the mismatch condition in Experiment 1 were due to partial overlap of the syntactic structure. The overall results showed that the priming effects observed in these experiments were syntactic in nature and independent of lexical/semantic priming. Keywords: syntactic structure, sentence comprehension, priming effects, scrambled word order, cross-modal priming ing reports as to how the phonological, syntac-

1. Introduction

tic, and semantic levels of language affect each

An extension of the Modularity Hypothesis

other. For example, Marslen-Wilson (1975) pre-

(e.g. Fodor, 1983; Forster, 1979) conceives the

sented experimental data that phonological or

language faculty as being divided into subcom-

lexical processes affect syntactic or semantic pro-

ponents. Under this view, phonology, syntax, se-

cesses. However, Swinney (1979) reported exper-

mantics and the lexicon are ‘sub-modules’ within

imental evidence for the independence of lexical

the language module.

The modularity of the

processing from contextual information by using

syntactic parsing mechanism, among other as-

the cross-modal lexical priming method. In some

pects in sentence processing such as phonologi-

ERP studies (e.g., Friederici, 2002; Friederici

cal/orthographic processing or lexical/semantic

& Kotz, 2003), it was suggested that syntac-

processing, has been a central research question

tic and semantic processing are independent of

of late. Many efforts to address this question use

each other by presenting the existence of different

behavioral and physiological approaches.

ERP components sensitive to conceptual (i.e., se-

In behavioral studies, there have been conflict-

mantic and pragmatic) violations (N400) or syntactic violations (LAN or Left Anterior Nega-

1. Graduate School of Education, Hiroshima University, 2. Ph. D. Program in Linguistics, Graduate Center at the City University of New York, 3. International Student Center, Hiroshima University.

tivity and P600).

In studies of aphasia (e.g.,

Hagiwara, 1998) and fMRI studies (e.g., Embick, Marantz, Miyashita, O’Neil, & Sakai, 2000;

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Cognitive Studies

Hashimoto & Sakai, 2002; Suzuki & Sakai, 2003),

June 2007

(e.g., Yamashita, Hirose, & Chang, 2003).

a wealth of data demonstrated the functional in-

There have been efforts to investigate syntac-

dependence of syntactic and semantic processing

tic priming effects in sentence comprehension.

in terms of the brain area activated in certain

In terms of materials and design, these previ-

specific processing, especially the Broca’s area

ous experiments, however, were not sufficient

when engaged in syntactic processing.

to separate syntactic information and lexical in-

Building upon these previous studies, the pur-

formation, and results on syntactic priming ef-

pose of the present research is to provide a new

fects in sentence comprehension were inconsis-

set of data for the functional independence of

tent. For instance, Frazier, Taft, Roeper, Clifton,

syntactic parsing by considering syntactic prim-

& Ehrlich (1984) reported shorter reading times

ing effects in Japanese sentence processing. A

for the second clause of a conjoined sentence

large body of observational and experimental ev-

when the syntactic forms of first and second

idence indicates that people tend to use a partic-

clause were similar than when these were differ-

ular syntactic structure if that structure has re-

ent. However, since the same verbs were used in

cently been employed. As an example of this ten-

two clauses in this experiment, the results could

dency (i.e., syntactic priming) in sentence pro-

be interpreted as the facilitative effect of not only

duction, Bock (1986) reported syntactic priming

syntactic processing but also lexical processing.

effects by using the guise of a memory test. In

Likewise, Branigan, Pickering, Liversedge, Stew-

her experiments, participants were instructed to

art, & Urbach (1995) reported syntactic prim-

repeat a prepositional object (PO) sentence like

ing effects in sentence comprehension only for

(1a) or a double object (DO) sentence like (1b)

sentences with local syntactic ambiguities. Al-

as prime.

though they claimed that the priming effects ap-

(1) a. The rock star sold some cocaine to an undercover agent. b. The rock star sold an undercover agent some cocaine.

peared when the parser has to choose among competing syntactic alternatives, they also implied that the syntactic priming effects could be observed in the absence of competition. In addition, in the field of brain imaging re-

Participants were presented a picture that was

search, Noppeney & Price (2004) demonstrated

not semantically related with a prime sentence

syntactic priming effects by using behavioral and

and could be represented by using PO or DO sen-

physiological (BOLD signal in fMRI) measures.

tences immediately after repeating one of these

In their fMRI study, activity in the left temporal

sentences. Then participants tended to describe

pole decreased when subjects read a series of sen-

the picture by using the same syntactic form as

tences with similar syntactic form than dissimi-

prime sentence. Bock (1986) also found priming

lar syntactic form. These authors argued that

effects with active and passive sentences. Other

when successive sentences followed the same syn-

studies have demonstrated syntactic priming ef-

tactic structure, it was less demanding for the

fects by using sentence completion (e.g., Picker-

reader to assign thematic roles to the sentence

ing & Branigan, 1998; Pickering, Branigan, &

arguments. However, this study relied on large

McLean, 2002), sentence recall (e.g., Potter &

number of repetitions and that areas of the right-

Lombardi, 1998) and picture description (e.g.,

hemisphere that are not normally thought to be

Branigan, Pickering, & Cleland, 2000; Cleland &

involved in syntactic parsing showed substantial

Pickering, 2003). Syntactic priming effects were

activation. And they implied that further re-

observed not only in English but also in Dutch

search would be needed to specify the contribu-

(e.g., Hartsuiker & Kolk, 1998) and Japanese

tions of lexical/sentential semantics and syntac-

Vol. 14 No. 2

Syntactic Priming Effects

175

tic frames in the processing of semantic-syntactic

2004) also suggested the existence of filler-gap

integration.

dependencies in Japanese sentence processing by

As such, there remains considerable scope for

reporting longer reading times of scrambled sen-

improvement upon previous studies of syntactic

tences and priming effects by reactivation of a

priming effects in sentence comprehension, espe-

scrambled constituent at the gap position.

cially with respect to experimental materials and

Since there is only a word order differ-

methods. The most important point in investi-

ence between (2a) and (2b), while phonologi-

gating syntactic priming effects is to separate the

cal/orthographic and lexical/semantic processes

effect of syntactic processing from other aspects

are equivalent, the scrambling phenomenon in

of language processing.

Japanese is ideal as an experimental stimuli for

The present study used Japanese sentences

separating syntactic processes from other as-

with canonical and scrambled word (or more pre-

pects of sentence processing such as phonolog-

cisely, phrase) order.

ical/orthographic or lexical/semantic processes.

(2) a. Takashi-ga

ringo-o

tabeta.

Takashi-Nom apple-Acc ate ‘Takashi ate an apple.’ b. Ringoi -o Takashi-ga

[ti ] tabeta.

apple-Acc Takashi-Nom gapi ate ‘Takashi ate an apple.’

We thus use sentences with canonical and scrambled word order to investigate the nature of syntactic priming effects in sentence comprehension.

2. Outline of Experiments In the present study, two experiments were conducted to examine whether the effects of syn-

Studies in theoretical linguistics (e.g., Saito,

tactic priming could be extracted independently

1985) suggested that the accusative NP in a

from the effects of lexical/semantic priming by

scrambled sentence like (1b) is fronted in the ini-

using acceptability judgment task with a cross-

tial position leaving a gap in its original position.

modal priming paradigm. Experiment 1 investi-

That is, Japanese scrambled sentences like (2b)

gated whether or not the speed of target sentence

have a more complex structure than (2a).

processing is different when the syntactic form

This implication was supported by some exper-

of the target sentence and the prime sentence

imental results that found the reading times or

were congruent or incongruent.

grammatical judgment times of scrambled sen-

that priming effects could be observed when the

tences like (2b) were longer than canonical sen-

syntactic form of the target sentence was iden-

tences like (2a) (e.g., Tamaoka, Sakai, Kawa-

tical to that of the prime sentence because par-

hara, Lim, Miyaoka, & Koizumi, 2005; Koizumi

ticipants would process the same syntactic form

& Tamaoka, 2004; Mazuka, Ito, & Kondo, 2002;

successively. In Experiment 1, however, all of the

Miyamoto & Takahashi, 2002a, 2002b, 2004).

prime stimuli were sentences, which have syn-

For instance, Tamaoka et al. (2005) reported

tactic structure, except the control baseline of

that the reaction times of canonical sentences

white noise; that is to say, the effects of the prime

were faster than scrambled sentences in Japanese

sentence which have syntactic structure and the

active sentences with transitive verbs, active sen-

prime stimulus which has no syntactic structure

tences with ditransitive verbs, passive sentences

could not be distinguished. It was not enough

with transitive verbs and potential sentences.

to conclude whether the effects of prime resulted

These consistent results supported the theoret-

from the similarity of the syntactic form by Ex-

ical linguistic accounts provided by Saito (1985)

periment 1 itself. Therefore, Experiment 2 was

and implied that the parser relates the initial po-

conceived to further investigate this problem.

sition of the accusative NP with the original position. Miyamoto & Takahashi (2002a, 2002b,

We predicted

Experiment 2 examined whether or not the

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Cognitive Studies

June 2007

speed of target sentence processing is different

congruent condition showed larger priming fa-

when the prime stimulus is a sentence or a se-

cilitation effects than the incongruent condition,

quence of nouns. We predicted that priming ef-

priming effects would be caused by the congru-

fects could be observed when the syntactic form

ency of syntactic structure between primes and

of the prime sentence and the target sentence

targets.

were identical, as in Experiment 1 and would not be evident when the prime was a sequence

3.1 Method

of nouns due to a lack of syntactic structure.

3.1.1 Participants

In either of these two experiments, a cross-

Forty-eight graduate and undergraduate stu-

modal priming design is used in order to avoid

dents (20 females and 28 males) at Hiroshima

facilitation effects at the level of visual or au-

University in Japan, all native speakers of

ditory processing level. Acceptability judgment

Japanese, participated in the first experiment.

task was required in each trial to ensure pro-

Ages ranged from 19 years and 1 month to 36

cessing of stimuli sentences.

years and 6 months, with the average age being

Although judg-

ment component itself included lexical or seman-

21 years and 5 months on the day of testing.

tic factors, these potential confounding factors are strictly controlled and counter-balanced by

3.1.2 Materials

comparing reaction time for exactly the same tar-

120 correct and 120 incorrect sentences were

get sentences with congruent primes or incongru-

prepared for the target sentence correctness de-

ent primes that contains exactly the same lexical

cision task.

or semantic contents. It is thus possible to say

ceptable Japanese sentences) consisted of 120 ac-

that syntactic processing can be separated from

tive sentences with transitive verbs. These 120

other aspects of language processing if priming

sentences were arranged in canonical order, and

effects could be observed only in the prime-and-

nominative case marked subjects (NP-ga) and

target congruent condition.

accusative case marked objects (NP-o) were then

3. Experiment 1

Correct ‘Yes’ responses (i.e.

ac-

swapped to create sentences of scrambled order. For example, the sentence Ken-Ichi-ga shukudai-

Using the priming paradigm, the first exper-

o wasureta (‘Kenichi forgot his homework’) was

iment tested whether or not native Japanese

altered to read shukudai-o Ken-Ichi-ga wasureta

speakers take shorter reaction times for the

(same meaning, only in scrambled order). Since

prime-and-target congruent canonical (SOV)

the canonical and scrambled sentences were iden-

and scrambled (OSV) structures than for the

tical in terms of word used, the difference in syn-

prime-and-target incongruent canonical (SOV)

tactic structure can be directly compared in re-

and scrambled (OSV) structures. The first pre-

action times and correct rates.

diction is that reaction times of the congruent

As shown in Table 1, six types of correct prime-

condition are significantly shorter than those of

target stimuli pairs were used in Experiment 1.

the control condition. The second prediction is

The first and second types of stimuli were white

that reaction times of the incongruent condition

noise primed sentences. The presentation time of

are significantly longer than those of the control

white noise (1,990ms) was the same as the aver-

condition or significant difference is not observed

age of the presentation time of sentence primes.

between two conditions. If the results tuned out

The third and fourth types of stimuli were canon-

as predicted, Japanese sentence comprehension

ical order (SOV) primed sentences, of which 40

would be shown to be affected by syntactic prim-

were prepared. The same number of the fifth

ing (i.e., priming effects). Furthermore, if the

and sixth stimuli was scrambled order (OSV)

Vol. 14 No. 2

Syntactic Priming Effects Table 1

Examples of stimuli in Experiment 1

prime

examples of prime

White Noise

White Noise

target SOV

OSV

canonical order (SOV)

177

Shinya-ga kimono-o nurashita Shinya-NOM cloth-ACC wetted ‘Shinya wetted the cloth’

SOV

OSV

shokubutsu-o Hitomi-ga sodateta. scrambled order (OSV) plants-ACC Hitomi-NOM grew ‘Hitomi grew plants’

SOV

OSV

examples of target Kenichi-ga shukudai-o wasureta. Kenichi-NOM homework-ACC forgot ‘Kenichi forgot his homework’ shukudai-o Kenichi-ga wasureta. homework-ACC Kenichi-NOM forgot ‘Kenichi forgot his homework’ Miyoko-ga gakkou-o yasunda. Miyoko-NOM school-ACC absented ‘Miyoko was absent from school’ gakkou-o Miyoko-ga yasunda. school-ACC Miyoko-NOM absented ‘Miyoko was absent from school’ Nobuko-ga kaidan-o nobotta. Nobuko-NOM stairs-ACC climbed ‘Nobuko climbed the stairs’ kaidan-o Nobuko-ga nobotta. stairs-ACC Nobuko-NOM climbed ‘Nobuko climbed the stairs’

Note: SOV refers to canonical word order (Subject-Object-Verb) while OSV refers to scrambled word order (Object-Subject-Verb). NOM refers to nominative case while ACC refers to accusative case.

primed sentences. These three types of white

and second types of stimuli were white noise

noise, SOV and OSV prime stimuli were further

primed sentences. The third and fourth types of

divided into SOV canonical or OSV scrambled

stimuli were primed sentences that had the same

target sentences. Classified in this way, the ex-

syntactic form as target sentence. The fifth and

periment examined the effects of syntactic prim-

sixth stimuli were primed sentences that had dif-

ing on Japanese sentence processing.

ferent syntactic forms than the target. These two

It was expected that reading times would be-

types of white noise, congruent and incongru-

come faster when participants saw sentences con-

ent prime stimuli were further divided into SOV

taining the same words. Thus, to prevent the

canonical or OSV scrambled target sentences. A

problem of repeatedly encountering the same

counter-balanced, Latin-square design was used

words, a Latin-square design was used to assign

to assign different sentences to participants. In

different sentences to participants. Six lists of

other words, six lists of sentences were given to

sentences were given to six groups of partici-

six groups of participants. Each list consisted of

pants. Each list consisted of 20 sets of prime-

20 sets of prime-target stimuli in each category.

target stimuli in each category. In other words,

There was therefore a total 120 sets of prime-

there was a total 120 sets of prime-target stimuli

target stimuli for correct ‘No’ responses in each

for correct ‘Yes’ responses in each list.

list.

The equal number of correct ‘No’ responses

In addition, as fillers, various types (e.g. tran-

(i.e. 120 unacceptable sentences) were constructed.

sitive, intransitive, copular) of prime-target stim-

Scrambled sentences were created on the basis of

uli were prepared, with 60 sets of stimuli for both

canonical sentences. For example, the phrase or-

correct ‘Yes’ and ‘No’ responses used for each list.

der of the canonical sentence Kazushige-ga iwa-o

Consequently, a total of 360 sets of prime-target

matta (‘Kazushige waited for the rock’) was re-

stimuli in each list consisted of 180 stimuli for

arranged to iwa-o Kazushige-ga matta. Six types

correct ‘Yes’ responses and 180 stimuli for cor-

of prime-target stimuli pairs were created in the

rect ‘No’ responses.

same way as correct ‘Yes’ responses. The first

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Cognitive Studies Table 2 target

SOV

OSV

June 2007

Reaction Times (ms) and Correct Rates (%) in Experiment 1 prime

White Noise Cong. (SOV) Incong. (OSV) White Noise Cong. (OSV) Incong. (SOV)

Reaction Times (ms) M 1,434 1,352 1,388 1,603 1,542 1,563

SD 282 273 263 366 319 337

prime ∆ ∆82 ∆46 ∆61 ∆40

Correct Rates (%) M 97.60 96.46 96.77 92.40 90.73 89.58

SD 4.25 4.49 3.79 8.38 8.57 9.04

prime ∆ ∆1.14 ∆0.83 ∆1.67 ∆2.64

Note: M refers to means while SD refers to standard deviations.

3.1.3 Procedure

ble 2. Before performing the analysis, reaction

The presentation was controlled by a computer

times outside of 2.5 standard deviations at both

program, Microsoft Visual Basic 6.0 + Microsoft

the high and low ranges were replaced by bound-

DirectX 8. A cross-modal priming task was used

aries indicated by 2.5 standard deviations from

in order to avoid surface effects of the phonolog-

the individual means of participants in each cat-

ical/orthographic process. For each trial, a row

egory. A total of 122 data points of correct ‘Yes’

of crosses (++++++), indicating an eye fixa-

responses or 2.12 percent of the total of correct

tion point, was first presented in the center of

‘Yes’ responses (120 responses × 48 participants

a screen. When subjects pushed the NEXT but-

= 5,760) were replaced in Experiment 1. The

ton, a prime sentence was aurally presented from

statistical tests which follow analyze both sub-

headphones, immediately after which a target

ject (F1 ) and item (F2 ) variability. Only stim-

sentence appeared on the screen. Participants

ulus items of correct responses were used in the

were instructed to respond as quickly and as ac-

analysis of reaction times and correct rates.

curately as possible in deciding whether or not the sentence made sense. Responses were reg-

3.2.1 Reaction times for correct ‘Yes’

istered by the pressing of keys marked ‘Yes’ or

responses

‘No’. The items were presented in random order.

The data for raw reaction times replicated find-

Twelve practice trials were given to the partici-

ings by Tamaoka et al. (2005) and others. Re-

pants prior to the commencement of the actual

peated t-tests showed that reaction times for

testing.

the white noise-SOV condition were significantly faster than those for the white noise-OSV con-

3.2 Analysis and Results

dition in both subject analysis [t1 (47) = 5.811,

Extremes among sentence correctness decision

p < .001] and item analysis, both in cases with

times (less than 500 milliseconds and longer than

[t2 (119) = 7.151, p < .001] and without strange

5,000 milliseconds) were recorded as missing val-

or awkward items [t2 (117) = 6.938, p < .001].

ues. Only one data point fell into this extreme

This result revealed scrambling effects on the

category. Since reaction times and error rates for

processing of Japanese unambiguous active sen-

correct ‘No’ response might include extra cog-

tences for correct ‘Yes’ responses.

nitive or emotional reaction caused by semantic

The priming effects were calculated by sub-

anomaly and might not reflect natural processes

tracting the congruent and incongruent prime

of sentence processing, we only report results for

condition from the white noise prime condi-

correct ‘Yes’ responses. The means of correct

tion.

‘Yes’ reaction times and correct rates for sen-

reported in Table 2. A series of a 2 (SOV or

tence correctness decisions are presented in Ta-

OSV target syntactic structure) × 2 (congru-

The averages of the priming effects are

Vol. 14 No. 2

Syntactic Priming Effects

179

ent or incongruent priming effects) analyses of

[F1 (1, 47) = 16.760, p < .001] and in item anal-

variance (ANOVA) with repeated measures for

ysis [F2 (1, 119) = 14.647, p < .001]. The SOV

priming effects of reaction times of correct ‘Yes’

incongruent condition (1,388ms) was also signif-

responses were conducted on reaction times (mil-

icantly faster than the white noise SOV condi-

liseconds), using subject (F1 ) and item (F2 ) vari-

tion both in subject analysis [F1 (1, 47) = 6.847,

ability. The main effect of the target syntac-

p < .05] and in item analysis [F2 (1, 119) = 4.508,

tic structure was not significant either in sub-

p < .05]. For the OSV conditions, the prime-and-

ject analysis [F1 (1, 47) = .290, n.s.] or in item

target OSV congruent (hereafter OSV congru-

analysis [F2 (1, 119) = .260, n.s.]. The main ef-

ent) condition (1,542ms) was significantly faster

fect of the prime-and-target congruency was sig-

than the white noise OSV condition (1,603ms)

nificant in subject analysis [F1 (1, 47) = 4.641,

both in subject analysis [F1 (1, 47) = 4.927, p