Individual Differences in Rapid Word Recognition and its Relation to Reading Ability

Laura Halderman1, Christine Chiarello1, Suzanne Welcome1, Christiana Leonard2, & Janelle Julagay1

1University of California, Riverside 2University of Florida

•Previous research has shown that the RVF gains access to the phonology and orthography of words early in word recognition (~30ms) (Halderman & Chiarello, 2005; Lavidor & Ellis, 2003)

•This same research suggests the LVF does not gain access to phonology, but it does demonstrate efficient orthographic processes early in word recognition (Halderman & Chiarello, 2005; Lavidor & Ellis, 2003)

•These studies did not include any measures of reading ability, so it is not known how individual differences contribute to rapid word recognition

•12 variables were used to predict Percent Correct performance on a task designed to measure the earliest moments of word recognition

Introduction

Methods

•100 participants (55 Females)

•Woodcock Reading Mastery Test Revised

•Word Identification

•Word Attack

•Passage Comprehension

•Wechsler Abbreviated Scale of Intelligence

•Verbal, Performance and Full-Scale IQ estimates

•Handedness Preference Questionnaire

•Adult Reading History Questionnaire

•Eight Divided Visual Field Experiments

•Lexical Decision

•Participants decide if a letter string is an English word

•LVF and RVF trials

•Word Naming

•Participants name a word aloud

•CVF, LVF and RVF trials

•Nonword Naming

•Participants name a letter string that is not word in English

•LVF and RVF trials

•Masked Word Recognition

•Participants choose the word presented in between two rows of visual masks

•CVF, LVF and RVF trials

•Semantic Decision

•Participants decide if a word shown is Natural or Manmade

•LVF and RVF trials

+ @#@#

+ BOAT

+ @#@#

+BOATBEAT

60 ms

30 ms

60 ms

4000 ms

Masked Word Recognition

Multiple Regression Results for CVF trials

Predictors

DV - Percent Correct

Variance of Sole Predictor

Unique Variance

(semi-partial2)

Beta t-value p value

Word ID %

Word Attack %

Passage Comprehension %

Verbal IQ

Performance IQ

Full-Scale IQ

Lexical Decision VF AVG

Word Naming 1 CVF

Nonword Naming VF AVG

Semantic Decision VF AVG

.13

.05

.14

.09

.12

.17

.12

.17

.13

.21

.03

.02

.00

.04

.03

.04

.01

.03

.00

.02

.26

-.22

.09

-1.37

-1.11

2.18

.13

.22

.11

.19

2.057

-1.888

.696

-2.505

-2.046

2.379

1.305

2.121

1.025

1.662

< .05

n.s.

n.s.

< .05

< .05

< .05

n.s.

< .05

n.s.

n.s.

Multiple Regression Results for LVF trials

Predictors

DV - Percent Correct

Variance of Sole Predictor

Unique Variance

(semi-partial2)

Beta t-value p value

Word ID %

Word Attack %

Passage Comprehension %

Verbal IQ

Performance IQ

Full-Scale IQ

Lexical Decision LVF

Word Naming 1 LVF

Nonword Naming LVF

Semantic Decision LVF

.06

.08

.11

.09

.07

.10

.10

.30

.11

.26

.00

.00

.00

.00

.00

.00

.00

.06

.00

.01

-.038

.081

.054

.418

.413

-.713

.036

.386

.073

.152

-.292

.665

.407

.729

.733

-.745

.352

2.812

.731

1.22

n.s.

n.s.

n.s.

n.s.

n.s.

n.s.

n.s.

< .01

n.s.

n.s.

Predictors

DV - Percent Correct

Variance of Sole Predictor

Unique Variance

(semi-partial2)

Beta t-value p value

Word ID %

Word Attack %

Passage Comprehension %

Verbal IQ

Performance IQ

Full-Scale IQ

Lexical Decision RVF

Word Naming 1 RVF

Nonword Naming RVF

Semantic Decision RVF

.15

.17

.09

.11

.08

.13

.33

.26

.16

.21

.00

.05

.03

.02

.02

.02

.06

.03

.00

.00

.068

.327

-.292

-.840

-.820

1.429

.369

.243

.034

.004

.581

2.948

-2.355

-1.652

-1.612

1.668

3.184

2.324

.350

.916

n.s.

< .005

< .05

n.s.

n.s.

n.s.

< .005

< .05

n.s.

n.s.

Multiple Regression Results for RVF trials

This research was conducted under the support of the National Institute of

Health grant DC 006957, awarded to the second and fourth authors.

Visual Field R-square F value (12, 84) p value

CVF .42 5.15 < .001

LVF .38 4.25 < .001

RVF .51 7.27 <.001

Conclusions

•Across all visual fields, Word Naming accounts for a significant amount of variance

•The processes underlying word recognition in Word Naming and Masked Word Recognition are highly correlated for all visual fields

•In both the Central and Right visual fields, basic measures of ability (IQ) and reading ability account for significant variance

•However, there are different significant predictors for central and right visual fields

•CVF - Word Identification and Verbal, Performance & Full-Scale IQ

•RVF - Word Attack and Passage Comprehension

•Additionally, performance on the Lexical Decision task was the strongest predictor for the RVF, suggesting the Left Hemisphere relies on the same rapid word decoding processes for Lexical Decision

•In conclusion, performance on Central visual field trials is not a simple combination of processes that occur in the Left and Right visual fields during rapid word recognition