The time-course of lexical activation in
Japanese two-character word recognition
An eye-tracking lexical decision study

Koji Miwa (University of Alberta)
Ton Dijkstra (Radboud University Nijmegen)Gary Libben (Brock University)
Harald Baayen (Eberhard Karls University)

ICPEAL 2012 (Nagoya, Japan)
October 27, 2012

Morphological Processes2 How do the whole and its parts
contribute to our recognition of acomplex entity as a coherent
meaningful unit ?
 Japanese and Chinese logographic(morphographic) two-character words
have a multiple layer of morphologicalcomplexity.
 How are two-character words (= mostcommon word type) recognized ?

Morphological Processes
Sub-lexical Model(Radical-driven Decomposition)

Supra-lexical Model

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Research Questions

1. What is the order of activating the constituents and the wholeword representations ?
2. What is the relative importance of the left and the rightconstituents in complex word processing ?
3. What is the role of attention ? (what do eye fixations reflect?)→ We conducted lexical decision with eye-tracking experiments (seeKuperman et al., 2009 for Dutch lexical decision with eye-tracking)→ We tested relevant lexical predictors in mixed-effects regression
modeling (Baayen, Davidson, & Bates, 2008).

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Lexical Decision with Eye-tracking

 Participants

21 Japanese speakers in Canada Materials

708 two-character words
708 nonwords(non-existing combination of characters) Procedure

472 words in one session * 3 sessions
Fixation point manipulation(Left, Central, Right)

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Lexical Predictors
Whole Word
Whole Word Frequency,
Google Doc Frequency (residualized)

Character
Left Kanji Frequency
Right Kanji Frequency

RadicalLeft Kanji Radical Frequency
Right Kanji Radical Frequency

FeatureWhole Word Strokes
Left Kanji Strokes (residualized)
Right Kanji Strokes (residualized)

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7

Response Time Analysis
FeatureRadicalRadicalnsns

Whole Word Strokes

Left Kanji Radical Freq

Right Kanji Radical Freq

Character

Character

Whole Word

Whole Word

- 56 ms- 43 ms- 175 ms

- 182ms

Left Kanji Freq

Right Kanji Freq

Whole Word Freq

Google Doc Freq

97 ms

Observed Eye Movements• When readers were motivated to read from right to left, more fixations wereneeded (effect size = 0.1 subgazes)• Eye movements were mostly character-based.

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Sub-lexical Radical-based Model’s
Prediction for 1st Subgaze Duration

9FeatureFeatureRadical

RadicalInhibitory
effectInhibitory
effectLarge
facilitatory
effectLarge
facilitatory
effectLeft Kanji Strokes

Right Kanji Strokes

Left Kanji Radical Freq

Right Kanji Radical Freq

Character

Character

Whole Word

Whole Word

Mediumfacilitatory
effectMediumfacilitatory
effectSmall
facilitation
orno effectSmallfacilitationorno effect

Left Kanji Freq

Right Kanji Freq

Whole Word Freq

Google Doc Freq

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1st Subgaze Duration Analysis
FeatureFeatureRadical

Radical

126 ms

59 ms

32 ms

- 31 ms

Left Kanji Strokes

Right Kanji Strokes

Left Kanji Radical Freq

Right Kanji Radical Freq

Character

Character

Whole Word

Whole Word

- 135 ms

24 ms

- 25 msns

Left Kanji Freq

Right Kanji Freq

Whole Word Freq

Google Doc Freq

112nd Subgaze Duration Analysis
FeatureFeature108 ms

43 ms

Radical

Radical
33 ms

ns

Left Kanji Strokes

Right Kanji Strokes

Left Kanji Radical Freq

Right Kanji Radical Freq

Character

Character

Whole Word

Whole Word

35 ms

- 55 ms- 83 ms- 90 ms

Left Kanji Freq

Right Kanji Freq

Whole Word Freq

Google Doc Freq

Smaller Font, Different Nonwords, Left Fixation& Analysis of 1st Fixation Durations:
Basic Results were replicated!
FeatureFeatureRadical

127 ms- 56 ms

32 ms

12Radicalns

Left Kanji Strokes

Right Kanji Strokes

Left Kanji Radical Freq

Right Kanji Radical Freq

Character

Character

Whole Word

Whole Word

- 119 ms

44 ms

- 46 msns

Left Kanji Freq

Right Kanji Freq

Whole Word Freq

Google Doc Freq

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1st Subgaze Duration Analysis
FeatureFeatureRadical

RadicalLeft Kanji Strokes

Right Kanji Strokes

Left Kanji Radical Freq

Right Kanji Radical Freq

Character

Character

Whole Word

Whole Wordns

Left Kanji FreqRight Kanji Freq

Whole Word Freq

Google Doc Freq

Summary
1. What is the order of activating the constituents and the whole word
representations ?
→ Effects of the characters were facilitaory, large, and more robust thaneffects of the whole word and the radicals during the earliest time frame(radical effects were small and inhibitory)
2. What is the relative importance of the left and the right constituentsin complex word processing ?
→ It is not an either-or issue. They contribute at different points in time.
3. What is the role of attention ?
→ Attention modulates lexical processes.

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Our Proposal:
Character-driven Processing Model

15• Effects of the characters werefacilitaory, large, and more robust
than effects of the whole word andthe radicals during the earliest timeframe (radical effects were small andinhibitory)• Given this, we propose a characterdriven processing model with a levelskipping assumption.

• Character-driven processing pattern
was found regardless of the font size
and nonword types.