Grammatical class of base word and use of morpholexical representations in reading aloud derived nouns
A comparison between children with dyslexia and young skilled readers
D. Traficante, M. Marelli, C. Burani, C. Luzzatti
University of Milano-Bicocca
May 8th, 2013
Premise
Several studies showed that complex word
processing can be influenced not only by the
properties of full form representations but also
by the features of morphemic constituents
(see, e.g., Alegre & Gordon, 1999; Baayen, Burani,
& Schreuder, 1997; Baayen, Dijkstra, &
Schreuder, 1997; Burani & Thornton, 2003; Katz,
Rexer, & Lukatela, 1991; Sereno & Jongman, 1997)
The role of morphemic constituents is more evident in the
case of
Ø  semantic and phonological transparency of the base +
affixes combination (Baayen, 1991; Marslen-Wilson, Tyler, Waksler, &
Older, 1994; Sandra, 1990)
Ø  a high number of derived and compound words sharing the
same base (derivational and compounding family size; de Jong,
Schreuder, and Baayen, 2000; Schreuder & Baayen, 1997)
Ø  the presence of a high frequency base in low frequency
words (Bradley, 1979; Burani & Laudanna, 1992; Colé, Beauvillain, & Segui,
1989; Marcolini, Traficante, Zoccolotti, & Burani, 2011)
Ø  the presence of long and productive suffixes, with no
homophonic forms (Bertram, Laine, Baayen, Schreuder, & Hyöna, 2000;
Bertram, Schreuder, & Baayen, 2000; Kuperman, Bertram, & Baayen, 2010).
…and what about
the grammatical category of the base?
Evidence for the role of the grammatical category
in several languages:
Ø  In English, verbs are recognized more slowly than nouns (e.g.,
Sereno & Jongman, 1997).
Ø  In Italian, verbs are recognized and read aloud more slowly than
both nouns (Colombo & Burani, 2002) and adjectives (Traficante &
Burani, 2003; Traficante, Barca, & Burani, 2004)
verbs are likely to be represented and
processed compositionally because they have a
high number of inflected forms sharing the
same verb base (Traficante & Burani, 2003).
when a morpheme is common to more words in
the language, its impact on processes of
morphological decomposition is prominent
(Deutsch, Frost, & Forster, 1998)
In processing derived words it might be easier
to access base morphemes that occur in many
word forms (i.e., verb bases), than bases
embedded in few forms (i.e., noun bases).
Why children with dyslexia?
Because children with dyslexia show the tendency
to a highly fractionated reading strategy (De Luca,
Borrelli, Judica, Spinelli, & Zoccolotti, 2002)
and are more
sensible to the presence of morphemic units, that
give them the opportunity of finding familiar and
meaningful letter chunks shorter than whole word
,
(Burani, Marcolini, De Luca,
& Zoccolotti, 2008)
Method
Participants
-  18 children with dyslexia (11 boys)
-  36 typically developing children (22 boys)
4th and 5th graders of two primary schools
in Milan
Typically developing children were matched to
children with dyslexia for gender, chronological
age, and non-verbal intelligence
Stimuli
Two groups of semantically transparent
derived words with frequent and productive
suffixes:
•  42 nouns derived from noun bases (e.g.,
artista, artist),
•  29 nouns derived from verb bases (e.g.,
punizione, punishment).
99 simple filler words, comparable to the derived words for
length, word frequency, and orthographic endings (e.g.,
condizione, condition) for a total of 170 stimuli
Reading aloud task :
Words singularly presented in the centre of a PC screen.
“Read it aloud as fast and as accurately as possible”
Procedure :
Fixation point (300 ms), followed by a brief interval (250 ms) and
by the stimulus.The onset of pronunciation, recorded by a
microphone connected to a voice-key, concluded each trial.
Word naming times (onset of pronunciation) of Nouns derived from
Verb bases and Nouns derived from Noun bases were analyzed.
Results (Latency)
Fixed Effect
Intercept
Group
Base Category
Base Frequency
Word Frequency
Suffix length
Word length
Group * Base Category
Group * Base Frequency
Group * Word Frequency
Base Category* Base Frequency
Base Category* Word Frequency
Base Category * Word length
Group * Base Category * Base Frequency
Group * Base Category * Word Frequency
Estim
7.1142
-0.4838
0.3103
0.0222
0.0061
0.0317
0.0735
-0.1982
-0.0297
-0.0063
-0.0614
-0.0709
-0.0602
0.0449
0.0380
p
0.0000
0.0000
0.0000
0.0891
0.5522
0.0234
0.0000
0.0000
0.0024
0.4111
0.0023
0.0000
0.0086
0.0022
0.0009
Results
Base category * Word length
Verb base
Noun base
Nouns with a noun base are more likely to be read through
sublexical strategies than long nouns with a verb base, that
can be decomposed in smaller morphemic units and be read
through lexical strategies
Results
Group * Base category * Base frequency
Children with dyslexia
Typically developing children
Verb base
Noun base
Verb base
Noun base
Results
Group * Base category * Word frequency
Children with dyslexia
Typically developing children
Verb base
Noun base
Verb base
Noun base
Conclusions
Ø  The suffix length effect, that has been
proved to be associated to morphemic parsing
processes (Kuperman, Bertram, & Baayen,
2010), shows that the activation of morphemic
units in reading aloud words in isolation can be
a time-costly strategy.
Ø  The interaction Base category * Word length can
be interpreted as evidence of the difficulty, for
children in 4° and 5° grades, in accessing wholeword representation in reading long complex words,
in particular when morphemic units smaller than the
entire word are not so easy to detect, as in the
case of noun bases.
The base frequency effect for words with a verb
base, is consistent with results of our previous
studies (Colombo & Burani, 2002; Traficante, Barca,
& Burani, 2004; Traficante & Burani, 2003): Italian
verbs are more likely to be processed through
morphemic units than nouns.
Accordingly, in the present study derived nouns are
more likely to be accessed through morphemes when
they have a verb base than a noun base.
Ø The apparently contradictory whole-word
frequency effect found in reading nouns
derived from a verb base can be interpreted
as the effect of the probability of finding
the specific combination of base + suffix
(Baayen, 2010).
So it can be due to the activation of the
combination of the two morphemic units and not
necessarily of the whole-word representation.
The use of the verb base morpheme is more
evident in less skilled readers, as children
with dyslexia.
Results (Accuracy)
Fixed Effect
Intercept
Group
Estimate
Z value
2.5621
6.275***
0.9871
Base category
5,9
6,00
5,00
2.656**
4,85
Base Category
Base Frequency
-0.6541
0.2354
-2.346*
2.082*
% Errors
4,00
3,00
2,00
1,00
Word Frequency
0.3239
3.588***
0,00
Noun base
Noun
base
Verb base
Verb
base
Conclusions
Ø Data on Accuracy reveal that in reading
aloud, using base morpheme as a headstart
for the pronunciation can lead to the
incorrect activation of a different suffix in
the case of verb base, due to the large
number of suffixes that can follow the first
morphemic unit.
Moreover…
The derivational suffixes which add to a verb base to derive
nouns are productive and frequent.
They refer to two main meanings, in an almost paradigmatic way:
the action expressed by the verb (-ata, -mento, -tura, -zione;
English: -ment, -tion) or the agentive (-ore, -tore, -trice, -nte;
English: -er, -ing).
Thus, an Italian reader usually finds the same verb base in
different words, combined with very productive and frequent
suffixes, in a consistent mapping of form and meaning.
On the contrary…
most of the derivational suffixes which add to noun bases are
combined with bases in a form-meaning mapping that is much
less consistent than in the case of verb bases:
e.g., the suffix –aio can express the person who sells
something (fioraio, florist), or the place in which you can find
a lot of something (pagliaio, haystack).
Results
1500
1250
1000
RT (ms)
750
500
250
0
Typically
Children with
developing
dyslexia
children
Ø The word length effect found in reading
nouns with a noun base shows the difficulty
of 4° and 5° graders in activating whole-word
representations when reading (6 - 11 letters)
long words. With these words, children cannot
activate a shorter unit (i.e., the noun base),
differently from the case of nouns with a
verb base. Consequently, in reading words with
a noun base, children are prone to use
sublexical strategies.