Studies on spelling in the context of dyslexia: a literature review

ABSTRACT

This paper aimed at reviewing the literature related to national and international research on spelling difficulties by dyslexics and identifying the intervention approaches performed with regard to this topic. An integrative review of the literature was carried out in order to answer the question: considering the domain of the orthography, one of the challenges frequently faced by dyslexics, how are studies on the relationship between dyslexia and spelling characterized? The research was carried out in PubMed platform, Scopus database and Portal de Periódicos CAPES/MEC. To search the articles, the following descriptors were used: "dislexia" or "dyslexia" with the free terms "ortografia" or "spelling". One aspect should be highlighted: some works indicate that difficulties in the spelling performance by dyslexics are not exclusively due to phonological processing failures - they are also secondary to alterations in orthographic processing. A challenge faced by dyslexics is to retain phonological information to use in writing new orthographic forms. Researchers suggest that intervention strategies include phonological, orthographic and lexical activities. It is observed that few studies have analyzed the difficulties that dyslexics face when dealing with new words, as well as writing, correctly, frequently used words in their own language.

Keywords:
Dyslexia; Handwriting; Learning

RESUMO

O objetivo deste estudo é revisar a literatura relacionada a pesquisas nacionais e internacionais sobre as dificuldades ortográficas enfrentadas por disléxicos e identificar as abordagens de intervenção na temática supracitada. Foi realizada uma revisão integrativa da literatura que buscou responder à pergunta: Considerando o domínio da ortografia um dos desafios frequentemente enfrentados por disléxicos, como se caracterizam os estudos a respeito da relação entre dislexia e ortografia? A pesquisa foi realizada na plataforma PubMed e nas bases de dados Scopus e Portal de Periódicos da Capes. Para pesquisar os artigos, foram utilizados da forma combinada os descritores “dislexia” ou “dyslexia” e os termos livres “ortografia” ou “spelling”. Um aspecto deve ser destacado: alguns trabalhos apontam que as dificuldades no desempenho da escrita por disléxicos não são decorrentes, exclusivamente, de falhas no processamento fonológico - são também secundárias a alterações no processamento ortográfico. Um desafio enfrentado por disléxicos é reter as informações fonológicas para utilizar na escrita de novas formas ortográficas. Pesquisadores sugerem que as estratégias de intervenção contemplem atividades fonológicas, ortográficas e lexicais. Observa-se que poucos estudos analisaram as dificuldades que disléxicos apresentam para lidar com palavras novas, bem como escrever ortograficamente palavras frequentemente utilizadas em sua própria língua.

Descritores:
Dislexia; Escrita Manual; Aprendizagem

Introduction

There is currently a constant concern from both medical and educational scope regarding difficulties on learning how to read and how to write.

Learning how to write is underpinned by a series of properties and aspects of the written form that are part of the orthographic system^1-3. This type of learning incorporates how to differentiate the formation of letters, to develop phonological awareness, to establish quantitative correspondence, to identify the position of letters in a word, to understand that the same letter may represent different sounds, as well as to understand that the same sound can be represented by different letters. Therefore, writing orthographically is not an easy task³.

The orthographic knowledge refers to the understanding of how letters are combined to form words, being acquired through repeated exposure, acquisition of phonological awareness and knowledge of the rules for the formation of the orthographic mental lexicon^3,4.

Spelling errors are part of the infant’s learning process^1,3,5. Although kids progressively overcome those errors as they obtain deeper understanding of the features of the orthographic system they use to write, the persistence of errors and the kind of errors they make might indicate some learning disability³.

Dyslexia as a functional learning disability is a neurological disorder characterized by specific difficulties in the reading and writing skills, which are not secondary of cognitive alterations, neither lack of opportunity in formal education⁶.

Researchers point out that, regarding dyslexia, the major focus of most studies has been reading difficulties, and there is less research about the orthographic processing in dyslexic children^2,3,5,7-9, although to correctly underline words be a challenge that might extend to adulthood¹⁰. Regarding learning problems, the investigation focus should not be limited to reading characteristics, it is necessary to understand the analysis of writing^3,11.

The main goal of this study is to revise scientific literature that is related to research about spelling difficulties faced by dyslexic, as well as to identify approaches of interventions on the aforementioned theme.

Methods

An integrative review of the literature based on national and international research was carried out to answer the following question: Considering the orthographic system skills one of the challenges most commonly faced by dyslexics, how are the studies about the relation between dyslexia and spelling characterized?

The research was carried out in PubMed platform, Scopus database and Portal de Periódicos CAPES/MEC. To search the articles, Descriptors in Health Science (DeCS) and Medical Subject Headings (MESH) were used in combination: “dyslexia” or “dislexia” and the free terms “spelling” or “ortografia”. Articles that were published within the last five years were selected through advanced search, excluding books. To search the combined terms, the option title/abstract was selected in the PubMed; title, abstract and keywords in the Scopus database and subject in the Portal de Periódicos CAPES/MEC.

The development of this article of literary review is part of a doctorate thesis, still under development, with the title “Dyslexic Sight Words (DSW) and Speech Therapy Intervention in Dyslexic children”, from the Graduate program of Sciences of Language at Universidade Católica de Pernambuco - UNICAP/PE.

In this research, complete original articles or review articles published in the last five years in Portuguese or English were included, which answered the guiding question and which addressed the theme established by the descriptors and free terms.

Articles that repeated were excluded. The following exclusions were also carried out: review articles about the symptoms of dyslexia; research about orthography with non-dyslexic; neuroimaging study with dyslexics; articles about reading and dyslexia, specifically; research with dyslexics about spelling regarding the sounding out of words, instead of writing down words; articles about the executive and neuropsychological functions of dyslexia; generic studies about dyslexia, and articles about “acquired dyslexia” due to vascular cerebral accident.

Literature Review

The analysis of the data was divided into stages. Firstly, all articles obtained through the combination of descriptors and terms “dislexia” AND “ortografia” AND “dyslexia” and “spelling” were identified, and all abstracts were read. Afterwards, the first part of exclusion, which followed the benchmarks of this research, was realized.

All remaining articles were separated to be read in full and the repeated articles were removed. After thorough reading, other articles were eliminated because they did not meet the criterion stablished initially (Figure 1).

Figure 1:
Flowchart showing the number of articles found and selected after applying inclusion and exclusion criterion

The selected articles were organized from the earliest to the latest according to the date of publication and, after reading each one, the following information was declared: author(s) and year of publication, constitution of sample, and description of study (Figure 2).

Figure 2:
Description of selected studies

The data search resulted in a total of 454 articles. At PubMed, as result of the combination of terms, 136 articles were found, at Scopus database, 251 articles were found, and at Portal de Periódicos da Capes, 67 articles were found.

When taking into consideration the inclusion and exclusion benchmarks, 36 articles were analyzed in this literature review.

The distribution of the number of publications that were included in this work about “dyslexia” AND “spelling” and “dislexia AND ortografia,” from 2012 to 2017 (in this last year, the period between January and April was considered) is presented in Figure 3.

Figure 3:
Distribution of the number of publications considered in this study on dyslexia and spelling and dislexia and ortografia in the period from 2012 to 2017, by year of publication

During the search for articles stage, even with the limitation of the free terms and/or descriptors, many works that focused on reading and dyslexia were found. In order to illustrate, an additional research of the terms dyslexia AND reading, dislexia AND leitura, dyslexia AND spelling, and dislexia AND ortografia, in the last ten years, was performed using the same benchmarks disclosed in the beginning of this session. In Figure 4, it is possible to verify superiority regarding the number of publications about dyslexia and reading when compared to the number of publications about dyslexia and spelling.

Figure 4: Distribution
of the number of publications regarding the combination of dyslexia and reading and dyslexia and spelling in the last ten years

The data related to the analysis of the study selected for this review are presented in Figure 2.

Among selected articles, two publications were computed in the year 2017, sixteen in the year 2016, seven in the year 2015, four in the year 2014, five in the year 2013 and two in the year 2012. A small number of publications is observed in 2017, which is justified by the fact that the search for articles was carried out during the months of March and April 2017. The articles published in 2016 correspond to 44.44% of the selected studies. There is a growing trend in the number of publications about dyslexia and spelling, as it can be observed, for example, between the years of 2014 and 2016 in Figure 3.

In dyslexia, spelling impairments are often more extensive and persistent than in reading. This may occur due to difficulties related to the process of phonographic-orthographic conversion and its use to the correct writing of the words^1-8. The analysis of the spelling errors made by children, in the educational and medical amplitude, might offer parameters for the identification of what is expected or not, assisting in the elaboration of plans and interventions according to the specificities of the difficulties¹².

A study carried out with Bosnian dyslexic children¹² validated the hypothesis of phonological deficit⁶ to explain the high frequency of errors in the writing of children with dyslexia, unlike results obtained in a Greek-language research¹³, with transparent orthography (greater phoneme-grapheme regularity). Studies suggest that different language structures produce different types of errors and that in languages that have a more transparent orthography there is a smaller incidence of errors⁹. In Greek there is less than half the syllables when compared to English (opaque orthographic system - irregular phoneme-grapheme relation)¹³.

The correspondence of a phoneme to a single grapheme and vice-versa is understood as orthographic transparency. However, orthographic opacity is characterized by the irregularity to which one grapheme might correspond to several phonemes, and to which one phoneme might correspond to many graphemes. This more opacity charactheristic of the language might generate some difficulties in the learning of the written language².

Research with Brazilian children¹ analyzed the spelling performance of dyslexic children and children with dyslexia and ADHD (Attention Deficit Hyperactivity Disorder) by administering dictation of words. The authors suggest that dictation using balanced words can be useful to the formation of a lexicon database that can be used in future research.

In some researches^1,14 the relationship between working memory or operational memory and spelling performance in children with dyslexia was studied. The writing process is complex and encompasses distinct functions that are integrated due to operational memory skills. Dyslexics present a working memory deficit that directly affects their writing tasks performance ¹⁴.

The occurrence of historic of oral language disorder is common in dyslexic children⁶. The spelling performance was investigated in a study with Italian dyslexic children¹⁵ with and without history of delay in the acquisition of the oral language. The results presented themselves coherent with the hypothesis that dyslexic children with history of oral language disorder present more severe orthographic deficit. The relation between reading fluency and spelling performance was the focus of the investigation of an American study¹⁶ which evaluated children with language disorder, dyslexic children and children with language disorder and dyslexia. It was concluded that the history of language disorder is not the cause of low spelling performance, and children that presented the gravest orthographic disorder had a reading deficit.

Some studies investigated the acquisition of English as a second language (L2), in dyslexics^17,18. The spelling performance and the most frequent types of erros were evaluated. Both studies demonstrated that the most frequent errors of dyslexics were of phonological nature.

Dyslexia is a learning disorder that affects word recognition during reading, spelling (sounding out letters) and writing. It is the result of a phonological processing deficit¹⁹. Phonological deficit hinders the learning of the alphabetical principle of the language, more specifically, the phoneme-grapheme correspondence²⁰. In languages such as French, this correspondence is the basic aspect for the successful learning of the reading and writing skills.

Dyslexic children are slower at spelling (sounding out letters) when compared to children with no specific learning disabilities^19,21. In a study that was performed with French non-dyslexic and dyslexic children¹⁹, spelling skills were analyzed through dictation of words. The phonological strategy was common to the groups, even though it was not guaranteed that children would be able to spell all words correctly. The visual-orthographic strategy (visual memorization of words) was observed only in non-dyslexic children. Researchers pointed out the importance of using the visual-orthographic strategy in intervention programs to promote the acquisition of new words by children.

Researchers have highlighted that, beyond phonological decoding difficulties, learning to read new words is a challenge to dyslexic children, especially sight words, which are common words in English language that children deal with in written materials throughout their whole schooling process²².

Spelling difficulties have been frequently observed in dyslexic children^{1,2,7-9,20,22} and persist until adulthood^14,23-27.

To some experts^1,2,9,15,17 errors made by dyslexic schoolchildren are likely to be classified in groups. As a result of a Brazilian research¹, it was presented that dyslexic schoolchildren and dyslexics with ADHD underperformed in writing when compared to children with no learning disorders. They made arbitrary spelling errors that are directly related to visual memory, knowledge of orthographic rules, lexicon and morphology.

The kind of phoneme-grapheme correspondence error depends on the phonetic/position context is a high frequency error category in dyslexic Brazilian children and dyslexic Brazilian children with ADHD¹. These errors are observed in the writing of irregular words of the Portuguese language, for example: feliz by felis, dança by dansa, visual by vizual, xícara by chicara, garrafa by garafa, longe by lonje, trouxe by trousse, colégio by coléjio, faixa by faicha, macarrão by macarão, lixo by licho, among others.

Researchers have investigated the spelling performance of Spanish dyslexic children¹¹ and pointed out that the most relevant difficulties in dyslexics are related to orthographic rules, writing of irregular words, and phoneme-grapheme conversion skill (vaso (cup) for baso, hueco (hollow) for ueco, chaqueta (jacket) for chaceta).

Errors of phonological nature were also the most frequently observed in a research with dyslexic Bosnian children¹². Phonological errors are result of the substitution of letters with similar pronunciation (biti by piti, slab by slap, zima by sima).

In a study performed with dyslexic and non-dyslexic French children⁸, the results demonstrated that all groups of children made the non-phonological error, for example: vert (green) by verre (cup). However, in another French study¹⁵, the spelling errors in dyslexic children were classified according to their nature, being the phonological ones the most frequent, for example: quota by cuota and febbre by febre.

The kind of lack or inadequate presence of accent was frequent in dyslexic Brazilian children as well¹, which is expected, as it is related to orthographic rules that are considered complex, such as notion of syllabic division and stress of words.

In a research with dyslexic and non-dyslexic undergraduate students, it was pointed out that the occurrence of a greater number of spelling errors made by dyslexics is not due to the fact they are less aware of their difficulties, but due to their own linguistic disability²⁷.

Research about learning disorder, in special dyslexia, have focused on the difficulties in acquisition of the correspondence between phoneme-grapheme^{12,18,22,28-30}. The phonic intervention is a way to stimulate phonological skills in advance in dyslexic children²⁹ and on children that present early learning profile with dyslexic characteristics or other learning disabilities⁴.

A study³¹ compared the spelling performance among children with dyslexia and children with ADHD. Its outcome suggested that intervention programs be distinct due to the specificity of each group. Dyslexic children made less errors when copying as compared to children with ADHD.

Researchers¹ emphasize that interventions regarding orthography must guarantee a systematic approach in the learning of the relation phoneme-grapheme, and afterwards in the learning of orthographic rules both for school children without learning disabilities and schoolchildren with learning disabilities. Researchers point to a failure in formal teaching of the aforementioned aspects.

A study performed with Dutch children²⁹ proposed a phonic intervention program based on spelling (sounding out letters) activities associated to cards that depict images related to their phonemes. In the results presented by the study, it was observed that the intervention program improved the performance of dyslexic children regarding reading, spelling (sounding out letters) and recognizing the relation between grapheme-phoneme. Operational memory activities associated to reading and writing were suggested to be introduced in the intervention program in the spelling difficulties of dyslexic children⁷. Dyslexic Hebrews were subjected to an orthographic intervention program through activities that involved morphological analysis of words⁵.

The use of information and communication technology (ICT), such as softwares that provide orthographic auto correction, tools for evaluation of reading and comprehension of texts, and e-readers, have assisted intervention of dyslexic children^14,25,32-36.

Research has tested non-dyslexic and dyslexic children while they performed orthographic tasks^37-40. It was suggested that evaluation activities on dyslexic children be as diversified as possible as children usually refuse to perform formal reading and writing tasks, which is justifiable due to their own learning disabilities⁴⁰.

Conclusion

This study addressed national and international publications about spelling in the context of dyslexia. It was observed that some studies in the literature highlight that the difficulties in the performance of the written language in dyslexic children are not exclusively due to phonological process fail, they are also secondary to alterations in the orthographic processing. Researchers suggest that beyond phonological activities, intervention strategies should address orthographic and lexical activities. Few studies analyzed the difficulties dyslexic children present to deal with new words in written material as well as to write correctly high frequency words in their mother language.

Acknowledgement

To Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) for granting the first author the financial support.

References

• ¹
  Alves DC, Casella EB, Ferraro AA. Spelling performance of students with developmental dyslexia and with developmental dyslexia associated to attention deficit disorder and hyperactivity. CoDas. 2016;28(2):123-31.
• ²
  Bigozzi L, Christian T, Pinto G, Gamannossi BA. Predicting dyslexia in a transparente orthography from grade 1 literacy skills: a prospective Cohort study. Read Writ Q. 2016;32(1):353-72.
• ³
  Zorzi JL. Processamento fonológico e ortográfico e suas implicações no diagnóstico dos transtornos de aprendizagem. In: Pantano T, Zorzi JL (orgs). Neurociência aplicada à aprendizagem. São José dos Campos. 2009. p. 141-55.
• ⁴
  Conrad NJ, Harris N, Williams J. Individual diferences in children's literacy developmental: the contribuition of orthographic knowledge. Read Writ. 2013;26(8):1223-39.
• ⁵
  Schiff R, Levie R. Spelling and morphology in dyslexia: a developmental study across the school years. Dyslexia. 2017;23(2):1-21.
• ⁶
  Lyon GR, Shaywitz SE, Shaywitz BA. Defining dyslexia, comorbidity, teacher's knowledge of language and reading. Ann Dyslexia. 2003;53(1):1-14.
• ⁷
  Sanders EA, Berninger VW, Abbot RD. Sequential prediction of literacy achievement for specific learning disabilities contrasting in impaired levels of language in grade 4 to 9. J Learn Disabil. 2017;50(1):1-21.
• ⁸
  Daigle D, Costerg A, Plisson A, Ruberto N, Varin J. Spelling errors in French-speaking children with dyslexia: phonology may not provide the best evidence. Dyslexia. 2016;22(2):137-57.
• ⁹
  Giannouli V, Pavlidis GT. What can spelling errors tell us about the causes and treatment of dyslexia? Nasen. Supp Learn. 2014;29(3):244-60.
• ¹⁰
  Rothe J, Cornell S, Elena I, Schulte-Korne G. A comparison of orthograpic processing in children with and without reading and spelling disorder in a regular orthography. Read Writ. 2015;28(1):1307-32.
• ¹¹
  Suárez-Coalla P, Villanueva N, González-Pumariega S, González-Nosti M. Spelling difficulties in Spanish-speaking children with dyslexia. Infancia y Aprendizaje. 2016;39(2):275-311.
• ¹²
  Duranovic M. Spelling errors of dyslexic children in Bosnian language with transparent orthography. J Learn Disabil. 2016;49(2):1-11.
• ¹³
  Protopapas A, Fakou A, Drakopoulou S, Skaloumbakas C, Mouzaki A. What do spelling errors tell us? Classification and analysis of errors made by Greek schoolchildren with and without dyslexia. Read Writ. 2013;26(5):615-46.
• ¹⁴
  Hiscox L, Leonaviciute E, Trevor H. The effects of automatic spelling correction software on understanding and comprehension in compensated dyslexia: improved recall following dictation. Dyslexia. 2014;20(3):208-24.
• ¹⁵
  Angelelli P, Marinelli CV, Iaia M, Putzolu A, Gasperini F, Brizzolara D et al. Spelling impairments in Italian dyslexic children with and without a history of early language delay. Are there any differences? Front Psychol. 2016 ;7(1):1-13.
• ¹⁶
  McCarthy JH, Hogan T, Catts HW. Is weak oral language associated with poor spelling in school-age children with specific language impairment, dyslexia or both? Special Education and Communication Disorders Faculty Publications. Clin Linguist Phon. 2012;26(9):791-805.
• ¹⁷
  Palladino P, Cismondo D, Ferrari M, Ballagamba I, Cornoldi C. L2 spelling errors in Italian children with dyslexia. Dyslexia. 2016;22(2):158-72.
• ¹⁸
  Lockiewicz M, Jaskulska M. Difficulties of Polish students with dyslexia in reading and spelling in English as L2. Learn Individ Differ. 2016;51(1):256-64.
• ¹⁹
  Sumner E, Connelly V, Barnett AL. The influence of spelling ability on vocabular choices when writing for children with dyslexia. J Learn Disabil. 2016;49(3):293-304.
• ²⁰
  Ruberto N, Daigle D, Ahlem A. The spelling strategies of Francofone dyslexics students. Read Writ. 2016;29(4):659-81.
• ²¹
  Plisson A, Daigle D, Montesinos-Gelet I. The spelling skills of French-speaking dyslexic children. Dyslexia. 2013;19(2):76-91.
• ²²
  Wang HC, Nickels L, Castles A. Orthograpic learning in developmental surface and phonological dyslexia. Cognitive Neuropsych. 2015;32(2):2-22.
• ²³
  Afonso O, Suárez-Coalla P, Cuetos F. Spelling impairments in Spanish dyslexic adults. Front Psychol. 2015;6(1):1-10.
• ²⁴
  Berget G, Sandnes FE. Do autocomplete functions reduce the impact of dyslexia on information-searching behavior? The case of google. J Assoc Inf Sci Tech. 2016;67(10):2320-8.
• ²⁵
  Ostberg P, Backlund C, Lindstrom E. Convergent and diagnostic validity of STAVUX, a word and pseudoword spelling test for adults. Logoped Phoniatr Vocol. 2016;41(3):124-8.
• ²⁶
  Tops W, Callens MD, Bijn E, Brysbaert M. Spelling in adolescentes with dyslexia: errors and models of assessment. J Learn Disabil. 2014;47(4):295-306.
• ²⁷
  Tops W, Callens M, Desoete A, Stevens M, Brysbaert M. Metacognition for spelling in higher education students with dyslexia: is there evidence for the dual burden hypothesis. Plos One. 2014;9(9):1-7.
• ²⁸
  Breadmore HL, Carroll JM. Morphological spelling in spite of phonological deficits: evidence from children with dyslexia and otitis media. Appl. Psycholinguis. 2016;37(6):1439-60.
• ²⁹
  Tilanus EAT, Segers E, Verhoeven L. Responsiveness to intervention in chidren with dyslexia. Dyslexia. 2016;22(3):214-32.
• ³⁰
  Roy P, Shergold Z, Kyle FE, Herman R. Spelling in oral deaf and hearing dyslexic children: a comparison of phonologically plausible erros. Res. Dev. Disabil. 2015;36(1):277-90.
• ³¹
  Re AM, Cornoldi C. Spelling errors in text copying by children with dyslexia and ADHD symptoms. J Learn Disabil. 2015;48(1):73-82.
• ³²
  Cidrim L, Madeiro F. Information and Communication Technology (ICT) applied to dyslexia: literature review. Rev CEFAC. 2017;19(1):99-108.
• ³³
  Torrance M, Ronneberg V, Johansson C, Uppstad PH. Adolescent weak decoders writing in a shallow orthography: process and product. Sci Stud Read. 2016;20(5):375-88.
• ³⁴
  Berninger VW, William N, Tanimoto S, Thompson R, Abbott RD. Computer instruction in handwriting, spelling, and composing for students with specific learning disabilities in grades 4-9. Comput Educ. 2015;81(1):154-68.
• ³⁵
  Hsu JL. Exploring the relationships between the use of text message language and the literacy skills of dyslexic and normal students. Res. Dev. Disabil. 2013;34(1):423-30.
• ³⁶
  Donovan JL, Marshall CR. Comparing the verbal self-reports of spelling strategies used by children with and without dyslexia. Int J Disabil Dev Ed. 2016;63(1):27-44.
• ³⁷
  Binamé F, Danzio S, Poncelet M. Relative ease in creating detailed orthographic representations contrasted with severe difficulties to maintain them in long-term memory among dyslexic children. Dyslexia. 2015;21(4):361-70.
• ³⁸
  Morken F, Helland T. Writing in dyslexia: product and process. Dyslexia. 2013;19(3):131-48.
• ³⁹
  Doignon-Camus N, Seigneuric A, Perrier E, Sisti A, Zagar D. Evidence for a preserved sensitivity to orthographic redundancy and impaired access to phonological syllables in French developmental dyslexics. Ann of Dyslexia. 2013;63(2):117-32.
• ⁴⁰
  Serrano F, Delfior S. Spanish dyslexic spelling abilities: the case of consonant clusters. J Read Res. 2012;35(2):169-82.

• Research support source: Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES).

Publication Dates

• Publication in this collection
  Dec 2017

History

• Received
  06 July 2017
• Accepted
  06 Oct 2017