Semantic Radical Activation in Visual Japanese Compound Recognition:
Seeing the tree for the forest
Koji Miwa, Gary Libben, R Harald Baayen ― University of Alberta, Canada

Mega Lexical Decision (without Priming)

Mini Lexical Decision (with Priming)
1. Aim of the Experiment

3. Participants

1. Aim of the Experiment

3. Participants To investigate whether semantic radicals (orthographic morphemes)
are processing units in Japanese word recognition using twokanji character stimuli.

 30 native Japanese speakers participated in the experiment.

 12 native Japanese speakers were tested

2. Materials

 A lexical decision with priming paradigm was used.
 A semantic radical of a right character was repeatedly presented.
 Participants rated semantic transparency of each semantic
radical on a seven-point scale after To investigate radical activation by using the distributional andorthographic properties of semantic radicals.
properties of semantic radicals, without using a priming method.
 To study the role semantic radicals against the background of
a wide range other lexical effects.

 46 two-character prime-target word pairs with their semantic radical
shared (primed) 46 two-character word pairs with their semantic radical not shared(control) 46 two-character nonwords
Prime*Word

Morphology/
Translation

RadicalWord

Morphology/Translation

Radical

RadicalSharedPrimed空港

ku-ko‘airport’シ(water)

血液ketsu-eki‘blood’シ(water)Yes

Control

砂嵐

suna-arashi‘sandstorm’山(mt.)

血液ketsu-eki‘blood’シ(water)No

額縁gaku-buchi‘frame’糸(string)

円筆

N/A竹(bamboo)No

Backward Masks (200 ms)##

4. Procedure A vocabulary size test, a reading proficiency test anda background questionnaire were conducted to gaugeparticipants’ language experienceand proficiency.
 The study consists of three sessions.
 The location of a fixation point wasvaried for each session (left, right, centre) 472 words were presented
in each session.
 Throughout the experiment, participants
wore a head-mounted eye-tracker.

Target Stimulus

5. Results (RT analysis)

Word ? or Nonword ?

5. Results

Loadings of the original lexical predictors on each PC
Predictor

 There was no significant priming effect. In a post-hoc principal
component regression analysis, 21 lexical predictors were reducedto six principal components (PC).
 Three principal components were predictive The semantic radical of a left character slowed down RT,
while the semantic radical of a right character speeded up RT.

2. Materials
 708 Japanese two-character words were sampled randomly from
Amano & Kondo (2003) lexical database.
 Words with homophones were excluded.
 708 two-character nonwords were prepared:- 180 of these nonwords were derived from existing two-character words.
- The rest of the nonwords were random combinations of characters.

Fixation Point (1,000 ms)Prime Stimulus (230 ms)

TargetCondition

Non-word

4. Procedure

TypePrime
Properties

StrokeFeatures

Principal component dimension reduction andRegression analyses of each PC in lexical decision

RadicalProperties

Character
Properties

WordProperty

Lexical Predictors

PC1

PC3

Effects of RT in Previous Trial, Fixation Location-Trial Interaction
Fixation Location-Vocabulary Size Interaction, andChar1FamSize-Char2RadicalType Interaction

PC5

Prime

Log Prime Whole Word Freq

-0.204

0.174

0.005

PrimeLog Prime Right Kanji Type-0.199

0.182-0.108

PrimeLog Prime Right Kanji Token-0.2480.240-0.057

Prime

Prime Right Kanji AoA

0.234-0.282

0.292

Prime

Prime Right Kanji Stroke

0.263-0.133-0.033

StrokeLeft Kanji Stroke

0.036

0.152

-0.372

StrokeLeft Kanji Radical Stroke-0.063

0.385

0.062

StrokeRight Kanji Stroke

0.222

0.107

0.171

StrokeRight Kanji Radical Stroke

0.256

0.042

-0.023

RadicalLog Left Kanji Radical Type

0.186

-0.117-0.579RadicalLog Left Kanji Radical Token

0.032-0.016-0.520

RadicalLog Right Kanji Radical Type-0.3250.046-0.120

RadicalLog Right Kanji Radical Token-0.326-0.061-0.035

Radical

Radical Transparency

0.182

0.177

-0.120Character

Log Left Kanji Type-0.169

0.167

0.171

Character

Log Left Kanji Token-0.199-0.0430.107

Character

Left Kanji AoA

0.228-0.179-0.120Character

Log Right Kanji Type-0.257-0.231-0.079Character

Log Right Kanji Token-0.229-0.424-0.047

Character

Right Kanji AoA

0.299

0.252

0.134

Whole Word

Log Whole Word Token-0.069-0.432

0.099

27.7

11.0

7.6

Variance accounted for (%)

 Type frequency of 2nd (right) characters’ semantic radical was foundto be predictive and Interacted with family size of 1st (left) characters.
 Fixation point location interacted with Trial and individuals’
vocabulary size
Estimate and p-value of Predictors
Estimatep-value(Intercept)-6.1606

0.001

TotalStrokes

0.00350.001

EntropyStrokes

0.12790.028

TotalToken
Char2RadicalFamSize
Char1FamSize-0.0587
0.05040.0072

0.001
0.024
0.714

VocSize
Char2Grades-0.0150.0096

0.002
0.001

poly(PrevRT, 2, raw = TRUE)1
poly(PrevRT, 2, raw = TRUE)2

1.4728-0.0964

0.002
0.002

FixationLeft
FixationRight
Trial
Char2RadicalFamSize:Char1FamSize
FixationLeft:Trial-0.0929-0.0936-0.0201-0.0106-0.0525

0.102
0.048
0.001
0.020
0.001

FixationRight:Trial
VocSize :FixationLeft
VocSize :FixationRight-0.01890.00840.0051

0.002
0.001
0.001

This research was supported by a Major Collaborative Research Initiative Grant (#412-2001-1009) from the Social Sciences and Humanities
Research Council of Canada to Gary Libben (Director), Gonia Jarema, Eva Kehayia, Bruce Derwing, and Lori Buchanan (Co-investigators).