Characterizing different types of developmental dyslexias in French: The Malabi screener

ABSTRACT

Reading is a complex process involving multiple stages. An impairment in any of these stages may cause distinct types of reading deficits– distinct types of dyslexia. We describe the Malabi, a screener to identify deficits in various orthographic, lexical, and sublexical components of the reading process in French. The Malabi utilizes stimuli that are sensitive to different forms of dyslexia, including “attentional dyslexia”, as it is traditionally refered to, characterized by letter-to-word binding impairments leading to letter migrations between words (e.g., “bar cat” misread as “bat car”), and “letter-position dyslexia”, resulting in letter transpositions within words (e.g., “destiny” misread as “density”). After collecting reading error norms from 138 French middle-school students, we analyzed error types of 16 students with developmental dyslexia. We identified three selective cases of attentional dyslexia and one case of letter-position dyslexia. Further tests confirmed our diagnosis and demonstrate, for the first time, how these dyslexias are manifested in French. These results underscore the significance of recognizing and discussing the existence of multiple dyslexias, both in research contexts when selecting participants for dyslexia studies, and in practical settings where educators and practitioners work with students to develop personalized support. The test and supporting materials are available on Open Science Framework (https://osf.io/3pgzb/).

KEYWORDS:

• Letter position dyslexia
• attentional dyslexia
• migratable word pairs
• migratable words
• transposed letter words
• developmental dyslexia
• dyslexia screener

Disclosure statement

No potential conflict of interest was reported by the author(s).

Author note

This project received ethics approval from the Comite d'Évaluation Éthique d’Établissement (C3E) of the Paris-Saclay University (February 2018, project number 28).

Notes

1 Note that this particular type of error is linked to the deletion or addition of two separate letters that have two distinct grapheme-phoneme correspondences, as exemplified earlier. This error type should not be confused with geminate errors, where the reader incorrectly interprets a single grapheme-phoneme correspondence. For instance, mistakenly reading ‘dessert’ as 'desert'. Geminate errors may stem from a deficiency in the conversion of a geminate according to a multi-letter grapheme-phoneme correspondence rule, or from deficiency in the lexical route, when this is needed for the correct rendering of a geminate in a certain word.

2 In previously reported cases of selective deficits in letter position dyslexia and attentional dyslexia, readers did not make significant errors that could not be attributed to migrations. This distinction sets these selective categories apart from Visual-Orthographic Analysis, which encompasses a wide range of visual letter errors.

3 We have included the database of recorded errors for norms and dyslexics combined here, https://osf.io/3pgzb/.

4 To the degree that it was possible, we revisited these students with a second battery of tests to examine the possibilty that they had undiagnosed dyslexia. Several of these students were identified as having selective deficits.

Additional information

Funding

This work was supported by La Fondation Sciences Cognitives, Apprentissages et Handicap, Grant number 2007-00000006772, and by the Lieselotte Adler Laboratory for Research on Child Development.