Georgia Z. Niolaki

Varieties of developmental dyslexia in Greek children

The current study aimed to investigate in a group of nine Greek children with dyslexia (mean age 9.9 years) whether the surface and phonological dyslexia subtypes could be identified. A simple regression was conducted using printed word naming latencies and nonword reading accuracy for 33 typically developing readers. Ninety per cent confidence intervals were established and dyslexic children with datapoints lying outside the confidence intervals were identified. Using this regression-based method three children with the characteristic of phonological dyslexia (poor nonword reading), two with surface dyslexia (slow word naming latencies) and four with a mixed profile (poor nonword reading accuracy and slow word naming latencies) were identified. The children were also assessed in spelling to dictation, phonological ability, rapid naming, visual memory and multi-character processing (letter report). Results revealed that the phonological dyslexia subtype children had difficulties in tasks of phonological ability, and the surface subtype children had difficulties in tasks of multi-character simultaneous processing ability. Dyslexic children with a mixed profile showed deficits in both phonological abilities and multi-character processing. In addition, one child with a mixed profile showed a rapid naming deficit and another showed a difficulty in visual memory for abstract designs. Overall the results confirm that the surface and phonological subtypes of developmental dyslexia can be found in Greek-speaking children. They also indicate that different subtypes are associated with different underlying disorders.

Intervention for a multi-character processing deficit in a Greek-speaking child with surface dyslexia

A case study with a 12-year-old boy, R.F., who was a monolingual speaker of Greek is reported. R.F. showed slow word reading and a difficulty in spelling irregular words but not nonwords. Assessments revealed that R.F. did not appear to have a phonological deficit, but indicated impaired multicharacter processing ability for visually presented letter arrays. On the basis of previous research linking multicharacter processing and reading we developed an intervention aimed at improving R.F.s ability to report letter arrays of increasing length. Following a 9-week programme, improvement was observed, and investigation of R.F.s reading revealed gains in single word reading speed and accuracy. The findings support the significance of intervention studies for testing hypotheses regarding causal relationships among cognitive processes and the notion of specific profiles of developmental dyslexia/dysgraphia in both opaque and transparent orthographies.

Transfer effects in spelling from transparent Greek to opaque English in seven-to-ten-year-old children

The study investigated single-word spelling performance of 33 English- and 38 Greek-speaking monolingual children, and 46 English- and Greek-speaking bilingual children (age range from 6;7 to 10;1 years). The bilingual children were divided into two groups on the basis of their single-word reading and spelling performance in Greek. In line with predictions, we found that scores on an assessment of phonological awareness were a significant predictor of spelling in English for the bilingual children with stronger Greek literacy skill. Phonological awareness scores were also a strong predictor of spelling in Greek in the monolingual Greek-speaking children. For the bilingual children with weaker Greek literacy ability, spelling in English was predicted by performance in a test of visual memory. This was more in line with results for the monolingual English-speaking children, for whom spelling performance was predicted by visual memory and phonological awareness scores. Qualitative analysis of misspellings revealed that phonologically appropriate errors were significantly greater in the strong Greek literacy ability bilingual group than the weaker Greek literacy ability bilingual group. Stimulus analyses using regression techniques are also reported. The results are interpreted to suggest that in biliterates literacy processes are transferred from one language to the other (Mumtaz & Humphreys, 2002).

HelexKids: A word frequency database for Greek and Cypriot primary school children

In this article, we introduce HelexKids, an online written-word database for Greek-speaking children in primary education (Grades 1 to 6). The database is organized on a grade-by-grade basis, and on a cumulative basis by combining Grade 1 with Grades 2 to 6. It provides values for Zipf, frequency per million, dispersion, estimated word frequency per million, standard word frequency, contextual diversity, orthographic Levenshtein distance, and lemma frequency. These values are derived from 116 textbooks used in primary education in Greece and Cyprus, producing a total of 68,692 different word types. HelexKids was developed to assist researchers in studying language development, educators in selecting age-appropriate items for teaching, as well as writers and authors of educational books for Greek/Cypriot children. The database is open access and can be searched online at www.helexkids.org.

Intervention for a lexical reading and spelling difficulty in two Greek-speaking primary age children: Lexical intervention targeting spelling

ABSTRACT An intervention study was carried out with two nine-year-old Greek-speaking dyslexic children. Both children were slow in reading single words and text and had difficulty in spelling irregularly spelled words. One child was also poor in non-word reading. Intervention focused on spelling in a whole-word training using a flashcard technique that had previously been found to be effective with English-speaking children. Post-intervention assessments conducted immediately at the end of the intervention, one month later and then five months later showed a significant improvement in spelling of treated words that was sustained over time. In addition, both children showed generalisation of improvement to untrained words and an increase in scores in a standardised spelling assessment. The findings support the effectiveness of theoretically based targeted intervention for literacy difficulties.

A sublexical training study for spelling in a biliterate Greek- and English-speaking child

ABSTRACT RI is an emergent trilingual boy, literate in Greek and English, with difficulties in reading and spelling in both languages. Assessment with non-literacy tests revealed a deficit in phonological ability and in visual memory for sequentially presented characters. RI took part in a training programme that targeted sublexical spelling processes. Post-intervention assessment revealed improvement in reading and spelling in Greek but not in English. Assessments of lexical and sublexical skills showed improvement in nonword spelling and nonword reading for Greek. For English, there was some indication of improvement in nonword reading at delayed post-intervention testing, but no evidence of improvement in nonword spelling. Possible reasons for the difference in outcome for the two languages are considered, including the level of transparency of written Greek and English.