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How do roots and suffixes influence reading of pseudowords: A study ofyoung Italian readers with and without dyslexiaDaniela Traficantea; Stefania Marcolinibc; Alessandra Lucid; Pierluigi Zoccolottie; Cristina Buranic

a Department of Psychology, CRIdee, Catholic University of Milan, Milan, Italy b Department ofPsychology and Cultural Anthropology, University of Verona, Verona, Italy c Institute for CognitiveSciences and Technologies, Rome, Italy d Bambino Gesù Pediatric Hospital Scientific Institute - IRCCS,Rome, Italy e Department of Psychology, Sapienza University of Rome, Rome, Italy

First published on: 19 July 2010

To cite this Article Traficante, Daniela , Marcolini, Stefania , Luci, Alessandra , Zoccolotti, Pierluigi and Burani,Cristina(2011) 'How do roots and suffixes influence reading of pseudowords: A study of young Italian readers with andwithout dyslexia', Language and Cognitive Processes, 26: 4, 777 — 793, First published on: 19 July 2010 (iFirst)To link to this Article: DOI: 10.1080/01690965.2010.496553URL: http://dx.doi.org/10.1080/01690965.2010.496553

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How do roots and suffixes influence reading

of pseudowords: A study of young Italian readers with

and without dyslexia

Daniela Traficante1, Stefania Marcolini2,5, Alessandra Luci3,Pierluigi Zoccolotti4 and Cristina Burani5

1Department of Psychology, CRIdee, Catholic University of Milan, Milan,

Italy, 2Department of Psychology and Cultural Anthropology, University of

Verona, Verona, Italy, 3Bambino Gesu Pediatric Hospital Scientific Institute �IRCCS, Rome, Italy, 4Department of Psychology, Sapienza University

of Rome, Rome, Italy, 5Institute for Cognitive Sciences and Technologies,

Rome, Italy

The study explored the different influences of roots and suffixes in reading aloudmorphemic pseudowords (e.g., vetr-ezza, ‘‘glass-ness’’). Previous work on adultsshowed a facilitating effect of both roots and suffixes on naming times. In thepresent study, pseudoword stimuli including roots and suffixes in differentcombinations were administered to sixth-grade children with dyslexia (N�22)and skilled readers (N�44), matched for chronological age. Indeed, thesequential reading strategy of less proficient readers (particularly for pseudo-words) should favour the emergence of differences between left and rightconstituents (root and suffix, respectively) in reading performance. Resultsshowed that for both children with dyslexia and skilled young readers the onset ofpronunciation depended exclusively on roots, while there was no significant effectof suffixes. However, both roots and suffixes led to higher levels of accuracy thanmatched orthographic strings of letters. Posthoc regression analyses confirmedthe morphological nature of the root and suffix effects, over and above the effectsof the frequency of their orthographic patterns. Results indicate that the positionof the reading units within the letter string, as well as their differential effects onlatencies and accuracy, should be taken into account by models of morphologicalprocessing in word recognition and reading and by applied intervention research.

Correspondence should be addressed to Daniela Traficante, Department of psychology,

Catholic University, Largo Gemelli 1, 20123 Milano, Italy. E-mail: daniela.traficante@unicatt.it

The research reported in this paper was supported by MIUR-PRIN Grant 2005111248 to

Pierluigi Zoccolotti. The authors thank Dr Roberto Iozzino for making possible to examine

children at the Centre for Cognitive and Linguistic Disorders (ASL 1) in Rome.

LANGUAGE AND COGNITIVE PROCESSES

2011, 26 (4/5/6), 777�793

# 2010 Psychology Press, an imprint of the Taylor & Francis Group, an Informa business

http://www.psypress.com/lcp DOI: 10.1080/01690965.2010.496553

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Keywords: Morphological structure; Reading processing; Children with dyslexia;

Pseudowords.

INTRODUCTION

The present study focuses on the relative roles of roots and suffixes in

modulating reading aloud morphologically complex new words in children

with different reading expertise.

The role of morphemic constituents in word recognition has been mainly

studied in adults by means of the lexical decision task and various models of

morphological processing have been proposed. Sublexical models posit that

morphemic constituents of a stimulus are sequentially parsed and the

corresponding sublexical units feed-forward activation to the word level

(e.g., Taft, 1994). In contrast, supralexical models (Giraudo & Grainger,

2003) claim that activation of morphemes follows recognition of the full-form

representation. In dual-route models (Burani & Caramazza, 1987; Schreuder

& Baayen, 1995), visual stimuli activate in parallel both morphological

constituents (through a parsing route) and full-forms (through a direct route).

Distributional properties of both morphemes and whole words determine

who wins the race. Low frequency or new derived words, composed of high-

frequency roots and high-frequency/productivity affixes, should be the ideal

candidates to be accessed through morphological constituents.

Several studies have confirmed the role of root frequency in lexical

decision (e.g., Burani & Thornton, 2003; Cole, Beauvillan, & Segui, 1989),

while the role of the suffix is less clear. The presence of a high-frequency

derivational suffix in a pseudoword led to increased rejection times and

several false alarms in lexical decision, both in the presence and in the

absence of a real root (Burani, Dovetto, Thornton, & Laudanna, 1997;

Burani & Thornton, 2003). These results show the relevance of the right-end

constituent (the suffix) in the access to morphemes within a pseudoword

context.

On the other hand, with low-frequency words (Burani & Thornton, 2003,

exp. 3), only root frequency influenced lexical decision latencies; suffix

frequency did not exert any effect. In the case of low-frequency words, the

root (the first, left-end constituent) may provide a head start for the

morphological route, which can lead to activation of the word representation

through parsing of the constituent morphemes before the full form is

activated by the direct route (Bertram & Hyona, 2003). Activation coming

from the suffix (the second, right-end constituent) might occur too late in the

processing, in which case the suffix would be less relevant than the root in the

recognition process. These findings need to be accommodated within models

(Baayen, Schreuder, & Sproat, 2000) in which no difference is considered

among constituents occurring in different word positions.

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In reading aloud morphologically complex pseudowords, Burani et al.

(1997) found a facilitating effect of the presence of a derivational suffix.

Burani, Arduino, and Marcolini (2006) investigated the relative roles of roots

and suffixes in reading pseudowords. The presence of a root speeded namingirrespective of the presence of a suffix, whereas the presence of a suffix

produced weaker facilitating effects on naming times. The authors concluded

that roots provide a head start for naming. Nevertheless, the role of the

information deriving from the second constituent needs further investigation.

Some indications concerning the role of constituent position within the

word come from studies examining eye movements during silent sentence

reading. Niswander, Pollatsek, and Rayner (2000) showed that root

frequency of English derived words affected first fixation duration andthat whole-word frequency had an effect on gaze duration. Studies on Dutch

and Finnish compounds showed involvement of both the left and right

constituents (Hyona & Pollatsek, 1998; Kuperman, Bertram, & Baayen,

2008; Pollatsek, Hyona, & Bertram, 2000). They also showed that the

duration of the first fixation was influenced by the frequency of the first

morphemic constituent and frequency of the second morpheme affected gaze

duration and later processing. Bertram and Hyona (2003) claimed that

morphological effects are more likely to emerge when stimulus processingrequires more than one eye fixation.

Although sixth-grade readers may already resemble adults regarding the

size of their perceptual span in reading (Haikio, Bertram, Hyona, & Niemi,

2009; Rayner, 1986), less proficient readers have a smaller perceptual span

that may lead to difficulties in identifying most words in one piece. In order

to study the differential roles of left vs. right morphemic constituents it might

be useful to present morphologically complex words and pseudowords to

readers who have less developed decoding skills and show analytical andfractionated text scanning, like beginning readers or children with dyslexia

(De Luca, Borrelli, Judica, Spinelli, & Zoccolotti, 2002; De Luca, Di Pace,

Judica, Spinelli, & Zoccolotti, 1999; Hutzler & Wimmer, 2004). Given the

sequentiality of the reading process of less proficient children, particularly

for pseudowords (Coltheart, Rastle, Perry, Langdon, & Ziegler, 2001), left

and right constituents might affect the reading performances of these

children to different extents. First, however, it would be useful to determine

whether young readers and children with dyslexia make use of morphemicunits in reading aloud.

The use of morphemic units in typically developing readers and in

children with dyslexia emerged in several studies. In third- to sixth-graders,

younger children tended to read correctly the suffixes of phonologically

opaque derived words (e.g., ‘‘natural’’) and to mispronounce the base word

(Mann & Singson, 2003). Other studies showed that poor readers had

difficulty in reading opaque derived words (Carlisle, Stone, & Katz, 2001;

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Windsor, 2000), but benefited from the morphemic structure of transparent

words. Carlisle and Stone (2005) found that children in both the lower

(second and third) and upper (fifth and sixth) elementary grades were more

accurate in reading derived words with transparent structure, but only thelower grade students were also faster on the transparent than the opaque

items. Furthermore, they showed that middle and high school students read

phonologically transparent derived words more accurately than opaque

words, but only the younger ones read the former words more rapidly.

As for Italian, Burani, Marcolini, and Stella (2002) found an advantage in

reading pseudoword stimuli composed of morphemes (root�suffix) com-

pared to pseudowords without morphological structure (nonroot�nonsuf-

fix) in third- to fifth-graders. Similar results were reported for sixth-gradechildren with dyslexia and for second-grade readers (Burani, Marcolini, De

Luca, & Zoccolotti, 2008). Only younger readers and children with dyslexia

took advantage of morphological structure also in reading real words

(Burani et al., 2008; Marcolini, Traficante, Zoccolotti, & Burani, in press).

These findings show that morpheme-based reading is particularly useful

for children with dyslexia and for beginning readers and results in improved

reading performance on both new and real words. In fact, morphemes are

reading units of an intermediate size between graphemes, which lead toextremely slow and analytical processing, and words, which, for unskilled

readers, are too large units to be processed as a whole (Burani et al., 2008).

However, it is still unclear whether roots and suffixes differentially influence

reading aloud because of their position in the letter string. Clarification of

these issues is important for modelling reading processes.

Word morphology has been recently considered with particular interest

within the connectionist approach to reading. In connectionist models, the

units encode regularities deriving from probabilistic information aboutorthography, phonology, and semantics. Graded, nondiscrete morphological

structures emerge in the course of learning relationships among sounds,

spellings, and meanings of words (Gonnerman, Seidenberg, & Andersen,

2007). Within such framework, fluency in reading may depend on the ability

to forge links among frequently co-occuring letters and to store them as

patterns, connecting multiple systems (Wolf et al., 2009). Pagliuca and

Monaghan (2010) claimed that, for Italian, a transparent orthography with a

rich morphology, morphemes may emerge within the connections betweenorthography and phonology without the contribution of semantics (see also

Plaut & Gonnerman, 2000). In their connectionist model that successfully

simulated main results on morphological effects in reading Italian pseudo-

words aloud, no difference was made between root and suffix.

On the basis of the data available for Italian, it could be hypothesised that

the facilitation on reading performance is due to the activation of the root

only, because the left constituent is the access code to the lexicon (Taft &

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Forster, 1975), or because it occurs in the initial position in the stimulus

(Hyona, Bertram, & Pollatsek, 2004). In the present study, we aimed to

determine the relative influences of roots and suffixes in modulating reading

aloud of children with different rates of fluency. Children with dyslexia mightpay less attention to the suffix than to the root, because of the extremely

sequential left-to-right scanning of the stimulus. On the other hand, sixth-

grade proficient readers might be able to take more advantage from the

right-end morphemic unit (the suffix) than children with dyslexia. Proficient

readers might apply a scanning strategy aimed at isolating the suffix, in order

to get information about stress assignment (Rastle & Coltheart, 2000), as

adults are prone to do (Burani et al., 1997, 2006).

To assess these hypotheses, four types of complex pseudowords, consistingof two morphemic units (root�suffix), only one morphemic unit (root�no-

suffix or no-root�suffix), or no morphemic units (no-root�no-suffix) were

used. In a previous study on adults, which was based on the same stimuli

(Burani et al., 2006, exp. 3), roots had a strong effect on naming times,

whereas suffixes had a weaker effect. If this difference is due to the position

of the suffix in the stimulus, less skilled readers*and particularly children

with dyslexia*who typically present highly sequential scanning of the

stimulus, may show even stronger differential effects related to the positionof the morphemic units in the word than adults and reveal a prominent role

of the root. Moreover, from the developmental data on low-frequency

derived words (e.g., Carlisle & Stone, 2005), some distinction between

fluency and accuracy performance should be expected, with roots mainly

affecting reading latencies, possibly because of their role in providing

meaning (Elbro & Arnbak, 1996), and suffixes mainly affecting accuracy,

because of their effect to correct stress assignment on new stimuli (see, e.g.,

Jarmulowicz, Taran, & Hay, 2007, 2008). Finally, we will try to distinguishthe role of the morphological structure from that of the orthographical�phonological features (as assessed by bigram frequency), which represent a

critical factor in reading pseudowords.

METHOD

Participants

The reading level of 270 students, recruited from sixth-grade classes of a

junior high school in Milan, was assessed. Two groups participated to the

experiment: 14 children with dyslexia (five girls and nine boys) and 44 skilled

children (14 girls and 30 boys). Eight children (two girls and six boys),

examined at the Centre for Cognitive and Linguistic Disorders (ASL 1) in

Rome, were also included in the first group, adding up to a total of 22

children with dyslexia.

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Criteria for inclusion in the dyslexic group were scores of at least two

standard deviations below the mean score in typically developing popula-

tions for either speed or accuracy in text reading (MT Reading test,

Cornoldi, Colpo, & Gruppo, 1995) or in a single word-reading test (Subtest

No. 4 of the Battery for the Diagnosis of Developmental Dyslexia and

Dysorthographia; Sartori, Job, & Tressoldi, 1995). The MT test requires the

participant to read a passage aloud within a 4-min time limit; speed (no. of

syllables per sec) and accuracy (no. of errors) were scored. The word reading

(Subtest no. 4) requires reading a list of 112 words; speed (total time in sec),

and accuracy (no. of errors) were scored. All children with reading disorder

from the original sample were tested.

Children with dyslexia were compared to skilled children of the same

chronological age, whose performances on the MT reading test and on single

word-reading test were within one SD below the norm for both speed and

accuracy. Forty-four children falling within these criteria were available for

testing. The two groups were matched for gender, age, and nonverbal

intelligence (Raven’s Coloured Progressive Matrices) (Table 1). All children

had normal or corrected-to-normal vision.

TABLE 1Means and standard deviations (in parentheses) for age (in months), raw and

normative z scores on Raven’s Coloured Progressive Matrices test, on MT reading test,and on Subtest No. 4 of the Battery for the Diagnosis of Developmental Dyslexia andDysorthographia. Data are presented separately for children with dyslexia and skilled

readers and compared by means of Student’s t test

Children with dyslexia

(N�22)

Skilled readers

(N�44)

Student’s t

M Mean z M Mean z (on raw scores)

Chronological age 141.31 (4.0) 141.32 (4.2) �0.09

Raven’s test 28.23 (2.5) �0.03 (0.7) 29.96 (3.41) 0.31 (0.7) �1.16

Reading speed (MT test)

(no. of syllables per sec)

1.97 (0.4) 1.48 (0.5) 3.58 (0.6) 0.03 (0.4) �10.46*

Reading accuracy (MT

test) (no. of errors)

20.75 (7.7) 1.51 (1.24) 7.57 (4.5) �0.05 (0.6) 4.24*

Reading speed (Subtest 4)

(total time in sec)

170.09 (44.3) 1.88 (0.7) 83.89 (14.07) 0.02 (0.5) 8.47*

Reading accuracy

(Subtest 4) (no. of

errors)

12.38 (7.68) 5.93 (4.1) 1.96 (1.8) 0.41 (1.1) 4.89*

*pB.001.

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Materials and design

The materials were the same as those used by Burani et al. (2006, exp. 3).

Four sets of 16 pseudowords were generated (see Appendix A): pseudowords

in the first set (root�suffix, e.g., bagnezza) consisted of a root (bagn-,

‘‘bath’’) and a derivational suffix (-ezza, ‘‘-ness’’) in a combination not

existing in the Italian language. Pseudowords in Set 2 (root�nonsuffix, e.g.,

bagnezzo) included the same root (bagn-) used in the first set, followed by an

orthographic sequence (-ezzo*) not corresponding to a real Italian suffix.

Pseudowords in Set 3 (nonroot�suffix, e.g., bognezza) were formed of

orthographic sequences (bogn*) that did not correspond to any existing root,

but were matched to the roots of the morphological sets for orthographic

structure and bigram frequency and included the same suffixes (-ezza) used

in the first set [difference on bigram frequency between 1 and 3 Sets: t(30)�1.02, p�.32, two-tailed]. Finally, pseudowords in Set 4 (nonroot�nonsuffix,

e.g., bognezzo) were formed of the same nonmorphemic orthographic

sequences*nonsuffix and nonroots, respectively*used in Sets 2 and 3.

Nonsuffixes in Sets 2 and 4 were matched for length, CV structure, and

average frequency in word-final position to the suffixes of Sets 1 and 3 (all

Student’s tB1.5, p�.1). Frequency values for roots, suffixes, and bigrams

were drawn from the child frequency count by Marconi, Ott, Pesenti, Ratti,

and Tavella (1993).The roots included in Sets 1 and 2 had very high frequency. The suffixes

occurring in Sets 1 and 3 were among the most frequent in Italian nominal

and adjectival derivatives. The nonroot sequences in Sets 3 and 4 were

obtained from the roots included in Set 1 by substituting one letter. The

nonsuffix sequences were the same in Sets 2 and 4, with the exception of two

item pairs, in which two different final sequences (-omo in Set 2 and -ede in

Set 4) were used to avoid the accidental inclusion of real words. Nevertheless,

these two sequences had a similar frequency and a similar CV structure. In

order to avoid embedding real words in the stimuli, some suffixes and

nonsuffixes were shifted across roots and nonroots in Sets 2 and 4. Stimuli in

the four sets had the same initial phonemes. Pseudowords in the four sets

were matched for length in syllables (all three syllables) and in letters (mean

length: 7.7 letters), suffix and nonsuffix frequency, F(3, 60)�.07, p�.97,

orthographic n-size F(3, 60)�1.92, p�.13, and mean bigram frequency,

F(3, 60)�1.80, p�.15 (Table 2).

Eight pseudoword fillers were added, two with the final nonsuffix -omo,

and six with the nonsuffix -ede, i.e., the nonsuffixes that were not exactly

matched in pseudoword Sets 2 and 4. Inserting these fillers allowed the same

number of repetitions of final sequences for each of the four experimental

sets, for a total of 72 items.

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Given that each root or pseudoroot was used (in different combinations)

in two experimental sets, we felt it was important to avoid morpheme

repetition effects. To accomplish this, the list of stimuli was divided into two

sublists, which were presented to participants in two experimental sessions

separated by at least 2 hours. Each sublist included half of the stimuli in each

set and each morphemic constituent occurred once. For each session, stimuli

were presented in two blocks of 18 items using different random orders. Each

block included a similar proportion of stimuli of the different experimental

and filler sets. The order of list, block, and stimuli within block presentation

was fully randomised. The experimental sessions were preceded by a training

block of 10 stimuli, that is, five words and five pseudowords.

Procedure

The stimuli were presented in the centre of the computer screen in black and

in lower case (font Courier New 18pt bold). Each trial consisted of the

following sequence: a fixation point for 300 ms; a blank stimulus for 250 ms;

the pseudoword, which remained visible until the onset of pronunciation or

for a maximum of 6,000 ms. Participants read aloud the pseudowords as fast

and accurately as possible. The children were tested individually in a quiet

TABLE 2Descriptive statistics on the matching variables for the experimental sets of pseudo-

words

Root�Suffix

Root�Nonsuffix

Nonroot�Suffix

Nonroot�Nonsuffix

Pseudoword length Mean 7.7 7.7 7.7 7.7

in letters SD 0.45 0.58 0.45 0.58

Pseudoword length Mean 3.0 3.0 3.0 3.0

in syllables SD 0 0 0 0

Root and Nonroot Mean 4.0 4.0 4.0 4.0

length SD 0.63 0.63 0.63 0.63

Root frequency Mean 585.19 585.19 � �SD 651.21 651.21 � �

Suffix and Nonsuffix Mean 837.25 866.50 837.25 763.38

frequency SD 844.63 390.07 844.62 342.45

Orthographic n-size Mean 0.25 0.06 0.12 0

SD 0.45 0.25 0.34 0

Bigram frequency Mean 8.57 8.86 8.38 8.68

SD 0.47 0.59 0.58 0.70

Note: Root, Suffix, and Nonsuffix frequencies are on one million tokens; bigram frequency

values are transformed on the basis of the natural logarithm. Frequency values for roots, suffixes,

and bigrams are drawn from the child frequency count by Marconi, Ott, Pesenti, Ratti, and

Tavella (1993).

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room at their school. A microphone connected to a voice-key recorded the

responses and the E-Prime software allowed measuring naming reaction

times (RTs) in milliseconds (ms). Mispronunciation errors were noted by the

experimenter.

Data analysis

Two kinds of analyses were carried out. The first, based on the factorialdesign, aimed at investigating the different roles of roots and suffixes in

reading pseudowords. It was carried out on (natural) log-transformed RTs by

means of a mixed effect model in which participants and items were crossed

independent random effects (Baayen, Davidson, & Bates, 2008), and group

(poor readers and skilled children), roots (roots and nonroots), and suffixes

(suffixes and nonsuffixes) were fixed factors. Accuracy, in binary form (0 1),

was analysed through a logistic linear model, in which group, roots, and

suffixes (as dummy variables) were the predictors.The second analysis was a posthoc regression aimed at discriminating the

role of orthographic patterns, measured by bigram frequency, from the role

of morphemic units, such as roots and suffixes (whose frequency was

computed by summing the frequency of all derived words including a given

morpheme) on RTs and accuracy. Five predictors were considered in the

analysis: one factorial, group (skilled children vs. children with dyslexia), and

four numeric predictors, i.e., the bigram frequency of the left part of the

string (corresponding to the root or to the nonroot unit), bigram frequencyof the right part of the string (corresponding to the suffix or to the nonsuffix

unit), (natural) log-transformed frequency of the root, (natural) log-

transformed frequency of the suffix. All correlations among the four numeric

predictors were nonsignificant with the exception of left constituent bigram

frequency with root frequency, r(64)�.32, pB.05. In order to assess whether

a predictor contributes significantly to explain the variance in the dependent

variable over and above the predictors entered before it in the regression

model, a sequential analysis of variance was used in the regression analysison RTs (Baayen, 2008, p. 183). As for accuracy, a logistic regression model

was fitted and a table listing the partial effects of the predictors was

obtained.

RESULTS

Invalid trials due to technical failures and out-of-time responses (�6,000 ms)

accounted for 5.4%, and 0.8% of the responses of children with dyslexia and

skilled readers, respectively. These trials were treated as missing data and

excluded from all analyses. Pronunciation errors were excluded from the

analyses on RTs and accounted for 31% and 11% of the responses of children

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with dyslexia and skilled readers, respectively. Vocal RTs for correctly named

items and percentages of errors are presented in Table 3.

Naming was faster for skilled young readers than for children with

dyslexia. Yet, in both groups the onset of pronunciation was a function of the

root only: this led to reliable facilitatory effects of 181 ms for children with

dyslexia and of 76 ms for skilled readers, respectively. There were no

significant effects of the suffix and no significant interactions (Table 4).

The analysis on accuracy showed main effects of group, root, and suffix

(Table 5). All interactions were far from significant. Children with dyslexia

had a lower level of accuracy than skilled readers, but in both groups the

TABLE 3Descriptive statistics by groups: mean reaction times with standard deviations in

parentheses and percentages of errors

Children with dyslexia Skilled readers

Root-Suffix Rt 1,982 (191.5) 863 (68.9)

% ERR 24 5

Root-Nonsuffix Rt 1,976 (283.6) 916 (82.0)

% ERR 30 11

Nonroot-Suffix Rt 2,106 (269.8) 982 (83.8)

% ERR 34 11

Nonroot-Nonsuffix Rt 2,214 (391.5) 949 (101.7)

% ERR 41 16

Root effect Rt �181 �76

% ERR �10.5 �5.5

Suffix effect Rt �50 �10

% ERR �6.5 �5.5

TABLE 4Reaction times: mixed effect model analysis

Df Sum sq Mean sq F value Estimate St. error t value

(Intercept) 8.33526 0.16951 49.17

Group 1 5.4163 5.4163 60.4579 �0.78154 0.09727 �8.03

Root 1 1.8121 1.8121 20.2270 �0.15600 0.06440 �2.42

Suffix 1 0.1935 0.1935 2.1596 �0.11726 0.06492 �1.81

Group*Root 1 0.0790 0.0790 0.8822 0.05406 0.03417 1.58

Group*Suffix 1 0.1340 0.1340 1.4961 0.06135 0.03445 1.78

Root*Suffix 1 0.0642 0.0642 0.7164 0.07825 0.08880 0.88

Group*Root*Suffix 1 0.1524 0.1524 1.7015 �0.06151 0.04716 �1.30

Note: AIC, 1,836; BIC, 1,904; logLik, �907.2; deviance, 1,774; REMLdev, 1,814. Number of

observations: 3,376; Groups: Subject, 66; Stimuli 64.

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presence of morphemic units, both roots and suffixes, led to more accurate

naming performance.

Since the stimuli are pseudowords, root and suffix effects might be

interpretable as orthographic effects. The multiple linear regression model

carried out on RTs showed that, apart from the main role of the group factor,

b��.72, t��40.82, pB.001, root frequency, b��.011448, t��4.256,

pB.001, is the most reliable predictor of RTs (Table 6) (effect size computed

according to Kuperman et al., 2008, p. 1128: �38 ms). Moreover, the

relevance of this predictor was still evident after considering the role of the

bigram frequency of the same sequence of letters, F�18.11, pB.001. Bigram

frequency of the right part of the string led to a delay relative to the mean

TABLE 5Accuracy: logistic linear model analysis

Factor Df Chi-square p value

Group (factor�higher order factors) 4 334.78 B.0001

All interactions 3 0.89 .8285

Root (factor�higher order factors) 4 38.24 B.0001

All interactions 3 2.53 .4704

Suffix 4 21.81 .0002

All interactions 3 2.41 .4913

Group*Root (factor�higher order factors) 2 0.57 .7516

Group*Suffix (factor�higher order factors) 2 0.46 .7934

Root*Suffix (factor�higher order factors) 2 2.18 .3360

Group*Root*Suffix (factor�higher order factors) 1 0.10 .7465

Total interaction 4 2.73 .6036

Total 7 367.05 B.0001

TABLE 6Reaction times: linear regression model

Estimate Std. error t value Pr(�jtj) F value Pr

(Intercept) 8.131996 0.106556 76.317 B2e�16

Group �0.718598 0.017604 �40.820 B2e�16 1660.0720 B2e�16

Left part bigram

frequency

�0.006532 0.010639 �0.614 0.5393 3.3866 0.06582

Right part bigram

frequency

0.016912 0.007852 2.154 0.0313 5.3990 0.02021

Log Root frequency �0.011448 0.002690 �4.256 2.14e�05 18.1065 2.146e�05

Log Suffix frequency �0.001226 0.002481 �0.494 0.6212 0.2443 0.62117

Note: Residual standard error: 0.4506 on 3,370 degrees of freedom. Multiple R2, 0.3336;

adjusted R2, 0.3326. F-statistic, 337.4 on 5 and 3,370 DF; p-value,B2.2e�16.

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level of speed showed by the intercept (effect size:�58 ms), making the

difference between orthographic and morphemic effects stronger.

As for accuracy (Table 7), both orthographic and morphemic features

showed significant effects but in opposite directions: higher bigram

frequency of both parts inhibited accuracy [Left part: b��.154,

Z��2.83, x2�8.00, pB.01; Right part: b��.163, Z��3.87, x2�14.98,

pB.001], while higher root and suffix frequency led to more accurate

naming [Root frequency: b�.0956, Z�6.83, x2�46.59, pB.001; Suffix

frequency: b�.0378, Z�2.91, x2�8.49, pB.005].

DISCUSSION

The results confirmed the influence of morphemic units in naming pseudo-

words. Both skilled young readers and children with dyslexia took advantage

of the presence of a root in the left part of the string of letters, like the adults

in Burani et al.’s (2006) study. A root in the initial part of the stimulus led to

faster and more accurate naming than a similar nonroot orthographic

sequence of letters in the same position. The sequential regression analysis

revealed that for both naming times and accuracy the effect of the root was

strong and significant over and above the effect of the frequency of its

orthographic patterns.

The suffix significantly affected accuracy but not RTs. The suffix effect

clearly emerged both in the mixed effects model and in the regression

analysis, where the frequency of the right-end morphemic unit was a good

predictor of performance. These data from young readers are partially

different from those on adults (Burani et al., 2006), since these showed a

suffix effect also on RTs (even though significant by participants only). The

difference might be due to the sequentiality of young readers’ naming, with

no clear-cut differences between typically developing readers and children

with dyslexia. It is worth noting that even children with dyslexia improved

TABLE 7Accuracy: logistic regression model

Estimate Std. error Wald Z

Pr

(�jtj) Chi-square Pr

(Intercept) 1.35118 0.55733 2.42 0.0153

Group 1.49734 0.08165 18.34 0.0000 336.33 B0.0001

Left part bigram frequency �0.15375 0.05436 �2.83 0.0047 8.00 0.0047

Right part bigram frequency �0.16301 0.04213 �3.87 0.0001 14.98 0.0001

Log Root frequency 0.09565 0.01401 6.83 0.0000 46.59 B0.0001

Log Suffix frequency 0.03779 0.01297 2.91 0.0036 8.49 0.0036

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their performances in the rather difficult task of pseudoword reading by

using morphemic constituents. In a transparent orthography like Italian, the

decoding deficit seems not to reduce the chance of forging morphemic

patterns. These results indicate the relevance of training programmes (e.g.,RAVE-O, Wolf et al., 2009; Wolf, Miller, & Donnelly, 2000) developed to

explicitly teach the use of morphological information*along with phono-

logical, orthographic, semantic, and syntactic knowledge*to increase fluent

reading and comprehension.

The present pattern of results emphasises the role of the constituent

position in the stimulus, by assigning a leading role to the first unit and

reducing the effect of the second one. Considering the results in Italian, the

head start to decomposition provided by the root emerged not only in lexicaldecision (Burani & Thornton, 2003) but also in naming and more evidently

in young readers than in adults for the applied naming strategies. These data,

along with the suffix effect on accuracy, are consistent with results on eye

movements in sentence reading, indicating that both morphemic constituents

(left and right) are important (Hyona & Pollatsek, 1998; Kuperman et al.,

2008) but exert different effects: the first influences the duration of the first

fixation while the second affects later processing (Pollatsek et al., 2000).

In understanding the role of morphemic units in reading it is worth notingthat their relevance cannot be explained by considering morphemes only as

high-probability sequences of graphemes, because the frequency of roots and

suffixes was a stronger predictor of naming performance than the frequency of

their bigrams. Thus, the peculiarity of the root in improving reading fluency and

accuracy does not stem only from its orthographic familiarity but also from the

regularity of the orthography-to-semantics mapping provided by the unit.

A similar claim can be made for the suffix, although its position does not

allow it to influence the onset of pronunciation. Hyona et al. (2004)discussed which type of information (orthographic or lexical) is picked up

from the second constituent while the first one is being fixated and proposed

that the information useful for processing could be primarily orthographic in

nature. Our results, however, indicate that the morpho-lexical information

drawn from the second constituent is not reducible to pure orthographic

information for at least two reasons. First, nonmorphemic final strings (e.g.,

ezzo), which had the same orthographic frequency and CV structure as

suffixes (e.g., -ezza), did not exert any facilitation effect. Second, in the caseof accuracy, the effect of the suffix was strong and significant over and above

the effect of the frequency of its orthographic patterns.

The suffix did not influence the onset of pronunciation (presumably

because of the sequential procedure used by young readers) but had a role

similar to the root in enhancing pronunciation accuracy. This finding might

be due to the effects of the suffix on the correct phonological rendering of a

new word. In Italian, assembling the pronunciation of (bound) root and

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suffix at the production stage implies assigning a stress to the root-suffix

combination that is different than the root stress. The second constituent

(i.e., the suffix) is crucial in such a process for its strong role as stress

attractor (see Jarmulowicz et al., 2007, 2008), affecting co-articulation of the

morphemic combination.The morphemic effects found in the present study on pseudoword naming

confirm that young readers use form-meaning regularities to segment new

written words, thus improving decoding and comprehension skills (see

Jarmulowicz, Hay, Taran, & Ethington, 2008). The present results can be

explained with reference to a morphologically decomposed lexicon, in which

both roots and suffixes are stored. Accordingly, they are compatible with

both sublexical (Taft, 1994) and dual route (Burani & Caramazza, 1987;

Schreuder & Baayen, 1995) models. However, the differential pattern of root

and suffix effects shown by children underscores the need of considering the

positions of the reading units within the letter string and their differential

roles in providing a head start to morphological decomposition (Bertram &

Hyona, 2003). As the root was effective independently of the presence of a

suffix (see also Burani et al., 2006), root representations must be activated as

soon as the (left-to-right) scanning of the stimulus identifies corresponding

orthographic patterns. Accordingly, models of reading that implement

morphological information have to include root representations along with

affix representations in the early stages of processing. Rastle and Coltheart

(2000) made an interesting attempt at modelling reading processing by

including morphemic units. However, since the authors claimed that the

pronunciation of polysyllabic stimuli is obtained by deriving suffix pronun-

ciation from the affix store (while the rest of the string is read via grapheme-

to-phoneme rules), their approach cannot explain the data from Italian

readers showing the prominent role of the root. This is better fitted by PDP

models (Gonnerman et al., 2007; Plaut & Gonnerman, 2000), as they

consider morphemic units as emerging patterns from orthographic, phono-

logical, and semantic representations. However, these models do not consider

the role of constituents’ positions in the stimulus. For example, the model

developed by Pagliuca and Monaghan (2010) does account for the

morphemic effects in reading pseudowords aloud by using connections

only between orthographic and phonological patterns, but it does not yet

consider the peculiar role of morphemic position.

Further efforts are needed to build a reading model that accounts for the

relevant role of morphemic unit position, the key function of the root in

accessing meaning (see also Elbro & Arnbak, 1996), and the importance of

the suffix for stress assignment and for its semantic and syntactic

information.

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REFERENCES

Baayen, R. H., Schreuder, R., & Sproat, R. (2000). Morphology in the mental lexicon: A

computational model for visual word recognition. In F. van Eynde & D. Gibbon (Eds.), Lexicon

development for speech and language processing (pp. 267�291). Dordrecht: Kluwer.

Baayen, R. H. (2008). Analyzing linguistic data: A practical introduction to statistics. Cambridge,

UK: Cambridge University Press.

Baayen, R. H., Davidson, D. J., & Bates, D. M. (2008). Mixed-effects modeling with crossed

random effects for subjects and items. Journal of Memory and Language, 59, 390�412.

Bertram, R., & Hyona, J. (2003). The length of a complex word modifies the role of morphological

structure: Evidence from eye movements when reading short and long Finnish compounds.

Journal of Memory and Language, 48, 615�634.

Burani, C., Arduino, L. S., & Marcolini, S. (2006). Naming morphologically complex pseudowords:

A headstart for the root? The Mental Lexicon Journal, 1, 299�327.

Burani, C., & Caramazza, A. (1987). Representation and processing of derived words. Language

and Cognitive Processes, 3, 217�227.

Burani, C., Dovetto, F. M., Thornton, A. M., & Laudanna, A. (1997). Accessing and naming

suffixed pseudo-words. In G. E. Booij & J. van Marle (Eds.), Yearbook of morphology, 1996

(pp. 55�72). Dordrecht: Kluwer.

Burani, C., Marcolini, S., De Luca, M, & Zoccolotti, P. (2008). Morpheme-based reading aloud:

Evidence from dyslexic and skilled Italian readers. Cognition, 108, 243�262.

Burani, C., Marcolini, S., & Stella, G. (2002). How early does morpho-lexical reading develop in

readers of a shallow orthography? Brain and Language, 81, 568�586.

Burani, C., & Thornton, A. M. (2003). The interplay of root, suffix and whole-word frequency in

processing derived words. In R. H. Baayen & R. Schreuder (Eds.), Morphological structure in

language processing (pp. 157�208). Berlin: Mouton.

Carlisle, J. F., & Stone, C. A. (2005). Exploring the role of morphemes in word reading. Reading

Research Quarterly, 40, 428�449.

Carlisle, J. F., Stone, C. A., & Katz, L. A. (2001). The effects of phonological transparency on

reading derived words. Annals of Dyslexia, 51, 249�274.

Cole, P., Beauvillan, C., & Segui, J. (1989). On the representation and processing of prefixed

and suffixed derived words: A differential frequency effect. Journal of Memory and Language,

28, 1�13.

Coltheart, M., Rastle, K., Perry, C., Langdon, R., & Ziegler, J. (2001). DRC: A dual route cascaded

model of visual word recognition and reading aloud. Psychological Review, 108, 204�256.

Cornoldi, C., Colpo, G., & Gruppo, M. T. (1995). MT Reading test: Guidelines. Firenze: O. S.

De Luca, M., Borrelli, M., Judica, A., Spinelli, D., & Zoccolotti, P. (2002). Reading words and

pseudo-words: An eye movement study of developmental dyslexia. Brain and Language, 80,

617�626.

De Luca, M., Di Pace, E., Judica, A., Spinelli, D., & Zoccolotti, P. (1999). Eye-movements patterns

in linguistic and non-linguistic tasks in developmental surface dyslexia. Neuropsychologia, 37,

1407�1420.

Elbro, C., & Arnbak, E. (1996). The role of morpheme recognition and morphological awareness in

dyslexia. Annals of Dyslexia, 46, 209�240.

Giraudo, H., & Grainger, J. (2003). A supralexical model for French derivational morphology. In

E. M. H. Assink & D. Sandra (Eds.), Reading complex words: Cross-language studies (pp. 139�157). New York: Kluwer.

Gonnerman, L. M., Seidenberg, M. S., & Andersen, E. S. (2007). Graded semantic and

phonological similarity effects in priming: Evidence for a distributed connectionist approach

to morphology. Journal of Experimental Psychology: General, 136, 323�345.

READING MORPHOLOGICAL PSEUDOWORDS 791

Downloaded By: [Burani, Cristina] At: 16:50 12 May 2011

Haikio, T., Bertram, R., Hyona, J., & Niemi, P. (2009). Development of the letter identity span in

reading: Evidence from the eye movement moving window paradigm. Journal of Experimental

Child Psychology, 102, 167�181.

Hutzler, F., & Wimmer, H. (2004). Eye movements of dyslexic children when reading in a regular

orthography. Brain and Language, 89, 235�242.

Hyona, J., Bertram, R., & Pollatsek, A. (2004). Are long compound words identified serially via

their constituents? Evidence from an eye-movement-contingent display change study. Memory

and Cognition, 32, 523�532.

Hyona, J., & Pollatsek, A. (1998). Reading Finnish compound words: Eye fixations are affected by

component morphemes. Journal of Experimental Psychology: Human Perception and Perfor-

mance, 24, 1612�1627.

Jarmulowicz, L., Hay, S. E., Taran, V. L., & Ethington, C. A. (2008). Fitting derivational

morphophonology into a developmental model of reading. Reading and Writing, 21, 275�297.

Jarmulowicz, L., Taran, V. L., & Hay, S. E. (2007). Third graders’ metalinguistic skills, reading

skills, and stress production in derived English words. Journal of Speech, Language, and Hearing

Research, 50, 1�13.

Jarmulowicz, L., Taran, V. L., & Hay, S. E. (2008). Lexical Frequency and third-graders’ stress

accuracy in derived English word production. Applied Psycholinguistics, 29, 213�235.

Kuperman, V., Bertram, R., & Baayen, R. H. (2008). Morphological dynamics in compound

processing. Language and Cognitive Processes, 23, 1089�1132.

Mann, V., & Singson, M. (2003). Linking morphological knowledge to English decoding ability:

Large effects of little suffixes. In E. M. H. Assink & D. Sandra (Eds.), Reading complex words:

Cross-language studies (pp. 1�25). New York: Kluwer.

Marcolini, S., Traficante, D., Zoccolotti, P., & Burani, C. (in press). Word frequency modulates

morpheme-based reading in poor and skilled Italian readers. Applied Psycholinguistics.

Marconi, L., Ott, M., Pesenti, E., Ratti, D., & Tavella, M. (1993). Lessico Elementare. Dati statistici

sull’italiano letto e scritto dai bambini delle elementari [Elementary Lexicon: Statistical data for

Italian written and read by elementary school children]. Bologna: Zanichelli.

Niswander, E., Pollatsek, A., & Rayner, K. (2000). The processing of derived and inflected suffixed

words during reading. Language and Cognitive Processes, 15, 389�420.

Pagliuca, G., & Monaghan, P. (2010). Discovering large grain-sizes in a transparent orthography:

Insights from a connectionist model of Italian word naming. European Journal of Cognitive

Psychology. DOI: 10.1080/09541440903172158.

Plaut, D. C., & Gonnerman, L. M. (2000). Are nonsemantic morphological effects incompatible

with a distributed connectionist approach to lexical processing? Language and Cognitive

Processes, 15, 445�485.

Pollatsek, A., Hyona, J., & Bertram, R. (2000). The role of morphological constituents in reading

Finnish compound words. Journal of Experimental Psychology: Human Perception and

Performance, 26, 820�833.

Rastle, K., & Coltheart, M. (2000). Lexical and nonlexical print-to-sound translation of disyllabic

words and nonwords. Journal of Memory and Language, 42, 342�364.

Rayner, K. (1986). Eye movements and the perceptual span in beginning and skilled readers.

Journal of Experimental Child Psychology, 41, 211�236.

Sartori, G., Job, R., & Tressoldi, P. E. (1995). Batteria per la valutazione della dislessia e

disortografia evolutiva [Battery for the Diagnosis of Developmental Dyslexia and Dysortho-

graphia]. Firenze: O. S.

Schreuder, R., & Baayen, R. H. (1995). Modeling morphological processing. In L. B. Feldman

(Ed.), Morphological aspects of language processing (pp. 131�154). Hillsdale, NJ: Lawrence

Erlbaum.

Taft, M. (1994). Interactive-activation as a framework for understanding morphological proces-

sing. Language and Cognitive Processes, 9, 271�294.

792 TRAFICANTE ET AL.

Downloaded By: [Burani, Cristina] At: 16:50 12 May 2011

Taft, M., & Forster, K. (1975). Lexical storage and retrieval of prefixed words. Journal of Verbal

Learning and Verbal Behavior, 14, 638�647.

Windsor, J. (2000). The role of phonological opacity in reading achievement. Journal of Speech,

Language and Hearing Research, 43, 50�61.

Wolf, M., Barzillai, M., Gottwald, S., Miller, L., Spencer, K., Norton, E., & Morris, R. (2009). The

RAVE-O intervention: Connecting neuroscience to the classroom. Mind, Brain and Education,

3, 84�93.

Wolf, M., Miller, L., & Donnelly, K. (2000). The retrieval, automaticity, vocabulary elaboration,

orthography (RAVE-O): A comprehensive fluency-based reading intervention program. Journal

of Learning Disabilities, 33, 375�386.

APPENDIX A: PSEUDOWORD STIMULI USED IN THEEXPERIMENT

Root�Suffix Root�Nonsuffix Nonroot�Suffix Nonroot�Nonsuffix

BAGNEZZA BAGNEZZO BOGNEZZA BOGNEZZO

CARTISMO CARTOSTA CURTOSO CURTOSTA

CODISMO CODOSTA CUDEZZA CUDOSTA

CORPEZZA CORPEZZO CURPISTA CURPEZZO

CUOROSO CUOROSTO CUONEZZA CUONOSTA

DONNISTA DONNOSTO DINNISMO DINNOSTO

ERBISTA ERBOSTA ERDISMO ERDOSTO

GITISTA GITOSTO GETISTA GETOSTO

GUERROSO GUERROMO GUARROSO GUARREDE

MAMMISTA MAMMOSTA MEMMISTA MEMMOSTO

PALLISMO PALLOSTO PILLISMO PILLOSTA

SONNEZZA SONNEZZO SANNISTA SANNEZZO

STELLOSO STELLOMO STOLLOSO STOLLEDE

STRADOSO STRADOMO STRODOSO STRODEZZO

VETREZZA VETREZZO VATREZZA VATROMO

ZAMPISMO ZAMPOMO ZEMPISMO ZEMPOMO

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