Word length and word frequency affect eye movements in dyslexic children reading in a regular (German) orthography

Abstract

We combined independently the word length and word frequency to examine if the difficulty of reading material affects eye movements in readers of German, which has high orthographic regularity, comparing the outcome with previous findings available in other languages. Sixteen carefully selected German-speaking dyslexic children (mean age, 9.5 years) and 16 age-matched controls read aloud four lists, each comprising ten unrelated words. The lists varied orthogonally in word length and word frequency: high-frequency, short; high-frequency, long; low-frequency, short; low-frequency, long. Eye movements were measured using a scanning laser ophthalmoscope (SLO). In dyslexic children, fixation durations and the number of saccades increased both with word length and word frequency. The percentage of regressions was only increased for low-frequency words. Most of these effects were qualitatively similar in the two groups, but stronger in dyslexic children, pointing to a deficient higher-level word processing, especially phonological deficit. The results indicate that reading eye movements in German children are modulated by the degree of difficulty, and orthographic regularity of the language can determine the nature of modulation. The findings suggest that, similar to Italian but unlike English readers, German children prefer indirect sub-lexical strategy of grapheme-phoneme conversion.

The effects of orthographic transparency and familiarity on reading Hebrew words in adults with and without dyslexia

“…We found that frequent words were read faster than less frequent words for both dyslexic and typical readers, but this effect was stronger for dyslexics. These results are in line with studies from transparent orthographies, showing that the effects of word frequency on reading latencies in dyslexics are equal or larger than in controls (Davies, Cuetos, & Glez-Seijas, 2007;De Luca et al 2008;Dürrwächter et al 2010;Rello et al 2013). In addition, these results support the suggestion that dyslexics are more vulnerable to reduced familiarity and frequency of the word patterns, due to low lexical quality of low frequency words.…”

Eye Movements during Silent and Oral Reading in a Regular Orthography: Basic Characteristics and Correlations with Childhood Cognitive Abilities and Adolescent Reading Skills

“…Note that we observed remarkable interindividual differences for the percentage of regressions (10–40% during silent reading, 10–35% during oral reading), which were neither associated with reading skills nor with total text reading time. However, with respect to the association between individual reading skills and the percentage of leftward eye movements, previous research has produced inconsistent results for readers of more regular orthographies (e.g., [ 10 , 17 , 31 , 32 , 34 – 36 ]). As suggested by Rayner [ 14 , 28 ], eye movement parameters are not only influenced by orthographic regularity, but also by factors such as the complexity or difficulty of texts and characteristics of font.…”

“…Previous research reported stable effects of reading proficiency on oculomotor control during silent reading (e.g., [ 9 , 10 , 34 , 35 , 41 ]), but less is known on this relation during oral reading (e.g., [ 17 , 20 – 22 ]). As articulation is a limiting factor to the maximum reading speed, the difference between these two reading modes is suspected to increase with reading proficiency and skilled readers generally favor silent reading over oral reading (e.g., [ 1 – 3 , 23 ]).…”

Atypical Balance between Occipital and Fronto-Parietal Activation for Visual Shape Extraction in Dyslexia

“…It is also possible that the limited temporal resolution of our behavioral measure obscured subtle group differences in latency. In either case, there is evidence from other studies with non-verbal tasks that individuals with dyslexia tend to exhibit behavioral deficits as a function of task difficulty for both verbal [57], [58] and non-verbal stimuli [21], [59], [60], [61], [62], [63]. Therefore, it may be that the minimal challenge of the task in the present study revealed functional brain differences that could lead to impaired behavioral performance in more demanding experimental conditions or during the reading of letters in the context of other letters or words.…”