The effects of transposed-letters on Arabic word
recognition.
Abubaker A A. Almabruk, Eman A. Gadalla, Kevin B. Paterson
Omar Al-Mukhtar University
2013-2014
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The effects of transposed-letter priming on Arabic word recognitions.
Abstract:
It has been an increasing interest in the effects of letter transpositions in word recognition
research in the recent years. The aim of the present experiment is to examine whether or not
root and word pattern letter-transpositions have similar effects when recognising Arabic
words. Using a lexical decision task, the word recognition performance of skilled Arabic
readers was examined. Participants were presented with real words and non-words. Results
indicated that Arabic real words were recognised quicker and more accurately than nonwords and more importantly the transposed-word-pattern-letter non-words were recognised
quicker and more accurately than transposed root letter non-words. These findings indicate
that transposed root letter has more effect in visual word recognition than transposed-words
pattern letter do in Semitic languages (e.g., Arabic).Implications of these findings for Arabic
word recognition are discussed.
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The effects of transposed-letter priming on Arabic word recognitions.
Background:
In recent years, it has been an increasing interest in the effects of letter transposition in word
recognitions research (e.g., Perea, Abu Mallouh, & Carreiras, 2010; Perea & Carreiras, 2006;
Schoonbaert & Grainger, 2004).The essential finding is that transposed-letter stimuli (such as
judge and jugde) have a large degree of perceptual similarity. Christianson, Johnson, and
Rayner(2005)found that a target stimulus (e.g., judge) is recognised faster when it is preceded
by non-word (e.g., jugde) than when it is preceded by non-word (e.g., jupte), in a lexical
decision task experiment. Frost, Forster, and Deutsch (1997)found that letter transposition
effects occurred in two tasks (lexical decisions and naming) when the targets and the primes
shared either a word pattern or root morpheme.
It has been stated that the letters of the root and the word pattern in Semitic languages might
be intertwined: the root and the word pattern form two abstract discontinuous morphemes
(e.g., Abu-Rabia & Awwad, 2004; Bentin & Ibrahim, 1996; Boudelaa & Marslen-Wilson,
2005, 2010). It has also been stated that lexical space in Semitic languages is not ordered in
orthographic terms ( like in Latinate languages), the reason being that, in Semitic languages,
lexical space is prearranged according to root relatives(Velan & Frost, 2009).
A recent study by Perea et al(2010) used masked priming in which prime words were formed
by either reordering letters in Arabic words that form the root or by transposing a root letter
with a word pattern form letter without reordering the root letters. The results showed that
priming effects were observed when the ordering of the letters of the root was kept intact but
not when the root letters were transposed, indicating that the order of the root letters is
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perceptually important for recognising words in Arabic. Semitic languages (e.g., Arabic and
Hebrew) are created from triliteral roots that comprise a sequence of three consonants that
express the general meaning of a word and combine with other letters (which form the word
pattern) to create different inflections of meaning(Boudelaa & Marslen-Wilson, 2010; Frost,
Kugler, Deutsch, & Forster, 2005). For example, Arabic roots comprising the consonants
(e.g.,k-d-r (‫ )قدر‬has the basic meaning of “to estimate”, and combines with other letters to
form words such as ‫”(مقدر‬mokder" meaning “estimated”) and ‫”( تقدير‬tekder" meaning
“estimation”). The roots in Arabic express the general meaning, but word patterns do not
combine the roots through affixation.
Arabic is considered as the second-most widely-used alphabet language in human societies,
after the Latin alphabet, and nevertheless Arabic is notably absent from transposed-letter
priming on Arabic word recognitions. Unlike languages formed from the Latin alphabet,
Arabic is formed in joined script in which spaces rarely exist between letters in word (e.g.,
hospital =‫)مستشفي‬, even when formally printed (Elanwar, Rashwan, & Mashali, 2007), and
also Arabic is read from right to left. Arabic letters share the same basic form and to the
extensive use of dots to mark distinctions between letters in Arabic script. For instance,
Arabic letters representing /t/ and /n/ (‫ )ت&ن‬become the graphemes that represent /th/ and /b/
(‫)ث&ب‬, respectively, simply by adding or changing the number or location of small dots
within the word(Almabruk, Paterson, McGowan, & Jordan, 2011).In this experiment we will
employ a transposed-letter manipulation in Arabic stimuli (words and non-words). In
particular, a lexical decision task was used to examine whether or not the root and the word
pattern letter-transposition have same effect when recognising Arabic words.
Methodology
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Participants: Eleven native Arabic speakers from the university students participated in this
experiment. All participants had normal or corrected-to-normal visual acuity, as determined
by a Bailey-Lovie Eye Chart.
Procedure: At the start of each session, participants were given instructions describing the
lexical decision task and emphasising the importance of speed and accuracy when
responding. On each trial a target word or non-word was shown for 150 ms at the centre of
the screen. Participants were required to decide whether the stimulus was a word or non-word
by pressing the appropriate key on the keyboard..
Design: Each participant was shown a total of 200experimental trials, presented in one
session. Word recognition was assessed using manual lexical decision (with appropriate
counterbalancing of hand of response). Accordingly, half of the participants responded using
their right (dominant) hand to press one of two keys on a response box and the other
participants used their left hand. For half of the participants in each of these groups, the left
key indicated a “word” response and the right key indicated a “non-word” response; this
arrangement was reversed for the other participants. Reaction times and errors were recorded.
Apparatus: Stimuli were presented in random order on a high-definition monitor and a
Cambridge Research Systems VSG 2/5 card controlled stimulus presentations and timing.
Responses were made via a Cambridge Research Systems CT3 keypad. The experiment was
conducted in a sound-attenuated and darkened room and displays were observed using a
chinrest to ensure a constant viewing distance.
Stimuli: A total of 200Arabic stimuli were used. Arabic words were taken from the Arelex
database (Boudelaa & Marslen-Wilson, 2010). The stimuli consisted of 50 Arabic real
words, 50 transposed-root-letter Arabic non-words, and 50 transposed-word-pattern-letter
non-words, with additional50 real Arabic words used as a filler condition.
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Results:
Figure 1: Reaction times and Error Rates for words and non-words. Bars correspond to 95% confidence interval
(e.g., Loftus and Masson, 1994).
The error rates and the reaction times for lexical decision for two non-words conations
stimuli were assessed using a repeated measures t-test. There was a significant difference in
the accuracy of responses for transposed word pattern letter non-words and transposed root
letter non-words, t(10) = 5.11, p<0.001, such that transposed word pattern letter non-words
were recognised more accurately than transposed root letter non-words. In addition, there was
a significant difference in reaction times, t(10) = 2.703, p<0.05, such that transposed word
pattern letter non-words were responded to more quickly than transposed root letter nonwords. Real Arabic words were recognised faster and with fewer errors than non-words.
Mean reaction times for correct responses and error rates for words and non-words are shown
in Figure 1.
Discussion:
The experiment reported here investigated the effects of transposed-letter primingon Arabic
word recognition using native Arabic participants. This was achieved by using lexical
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decision task to assess the recognition of Arabic words (and non-words) presented at the
centre of the screen. Results clearly show that native speakers of Arabic are more proficient
at recognising transposed-word-pattern-letter non-words than transposed-root-letter nonwords in the lexical decision task. This indicates that transposed root letters have a greater
effect on visual word recognition than transposed words patterns letters do in Semitic
languages (e.g., Arabic).
The present findings add additional evidence to the view that the root expresses the general
meaning in Arabic. For example, Frost et al., (1997),who have focussed on Hebrew
morphology, found that the three-consonantal root governs lexical effects in words
recognition than the word pattern does. An Arabic study by Perea et al. (2010) found that
letter transposition effects occurred only when the orders of the root letters were manipulated.
Possible explanations for these findings are:
First, the Arabic root comprising the consonants (e.g., h-s-l (‫ )حصل‬has the basic meaning of
“to achieve”, and combines with other letters to form words such as ‫"(محصول‬mahsul"
meaning “product”) and ‫"(تحصيل‬tehsil" meaning “achievement”). This means that the root has
the basic meaning in Arabic.
Second, the positions of the roots in Arabic are usually in the middle of the words, and
previous studies examining letter transpositions have found that the middle positions are
more important than the external positions.
Third, the Arabic language has a non-connective morphology in which the root and word
patterns do not combine via affixation, and the letters of these two components intermingle to
form a word. For example, in the word ‫"(تحصيل‬tehsil”), the root consonants appear as the
second, third, and final letters and are combined with other letters that form the word pattern.
Consequently, the root is not identifiable as a continuous sequence of letters, and must be
identified from a sequence of consonants spread throughout the word (e.g., (Boudelaa
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&Marslen-Wilson, 2005), and this may have important consequences for word recognition
(Perea et al., 2010; Velan & Frost, 2007, 2009).However, these explanations require
furtherinvestigation. For example, repeating the same study with more participants and
different word lengths.
References:
Abu-Rabia, S., & Awwad, J. (2004). Morphological structures in visual word recognition:
The case of Arabic. Journal of Research in Reading, 27(3), 321-336.
Almabruk, A. A. A., Paterson, K. B., McGowan, V., & Jordan, T. R. (2011). Evaluating
Effects of Divided Hemispheric Processing on Word Recognition in Foveal and
Extrafoveal Displays: The Evidence from Arabic. PLoS ONE, 6(4), e18131.
Bentin, S., & Ibrahim, R. (1996). New evidence for phonological processing during visual
word recognition: The case of Arabic. Journal of Experimental Psychology: Learning,
Memory, and Cognition, 22(2), 309-323.
Boudelaa, S., & Marslen-Wilson, W. D. (2005). Discontinuous morphology in time:
Incremental masked priming in Arabic. Language and Cognitive Processes, 20(1),
207-260.
Boudelaa, S., & Marslen-Wilson, W. D. (2010). Aralex: A lexical database for Modern
Standard Arabic. Behavior Research Methods, 42(2), 481-487.
Christianson, K., Johnson, R. L., & Rayner, K. (2005). Letter Transpositions Within and
Across Morphemes. Journal of Experimental Psychology: Learning, Memory, and
Cognition, 31(6), 1327-1339.
Elanwar, R. I., Rashwan, M. A., & Mashali, S. A. (2007). Simultaneous Segmentation and
Recognition of Arabic Characters in an Unconstrained On-Line Cursive Handwritten
Document. In C. Ardil (Ed.), Proceedings of World Academy of Science, Engineering
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and Technology, Vol 23 (Vol. 23, pp. 288-291). Canakkale: World Acad Sci, Eng &
Tech-Waset.
Frost, R., Forster, K. I., & Deutsch, A. (1997). 'What can we learn from the morphology of
Hebrew? A masked-priming investigation of morphological representation':
Correction to Frost et al. 1997. Journal of Experimental Psychology: Learning,
Memory, and Cognition, 23(5), 1189-1191.
Frost, R., Kugler, T., Deutsch, A., & Forster, K. I. (2005). Orthographic Structure Versus
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Perea, M., Abu Mallouh, R., & Carreiras, M. (2010). The search for an input-coding scheme:
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Perea, M., & Carreiras, M. (2006). Do transposed-letter similarity effects occur at a prelexical
phonological level? The Quarterly Journal of Experimental Psychology, 59(9), 16001613.
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Appendix
1-INSTRUCTIONS
This experiment examines of visual word recognition and will provide important information
for understanding normal Arabic reading processes.
In the experiment, you will be shown 2 types of stimuli. These will be either real Arabic
words or unreal Arabic words, and they will be shown one at the time at the centre of the
screen. Before each word is shown, at the start of each trial a single dot will appear at the
centre of the screen. You must look directly at this point. Once you’ve done this accurately,
the point will disappear and be replaced by either a real word or an unreal word. This will
stay on the screenfor a short time and your task is to indicate as quickly and as accurately as
possible whether or not what you see is a real word or not. You should do this by pressing
one of the buttons (either the left or the right button) on the response box in front of you. The
experimenter will tell you which button to use for “real” and “unreal” word responses.
Please respond as fast and accurately as you can; response times are an important part of this
experiment. The experiment will last approximately 25-30 minutes.
Don’t worry – the first few trials are practice trials so that you can familiarize yourself with
the procedure. Please note that, in line with the School’s ethics policy, you have the right to
withdraw from the experiment any time.