Early reading development in children at family risk for dyslexia.

In a 3-year longitudinal study, middle- to upper-middle-class preschool children at high family risk (HR group, N = 67) and low family risk (LR group, N = 57) for dyslexia (or reading disability, RD), were evaluated yearly from before kindergarten to the end of second grade. Both phonological processing and literacy skills were tested at each of four time points. Consistent with the well-known familiarity of RD, 34% of the HR group compared with 6% of the LR group became RD. Participants who became RD showed deficits in both implicit and explicit phonological processing skills at all four time points, clearly indicating a broader phonological deficit than is often found at older ages. The predictors of literacy skill did not vary by risk group. Both risk groups underwent a similar developmental shift from letter-name knowledge to phoneme awareness as the main predictor of later literacy skill. This shift, however, occurred 2 years later in the HR group. Familial risk was continuous rather than discrete because HR children who did not become RD performed worse than LR non-RD children on some phonological and literacy measures. Finally, later RD could be predicted with moderate accuracy at age 5 years, with the strongest predictor being letter-name knowledge.

Reliability and validity of the adult reading history questionnaire.

The reliability and validity of a revised version of Finucci's (1982) Reading History Questionnaire was examined in two adult samples. One sample included 84 adults from an ongoing study of familial dyslexia, and a second sample was composed of parents of 107 children from a longitudinal study of reading development. Internal consistency was demonstrated by Cronbach's alphas of .94 and .92 in the two samples. Test-retest reliability was demonstrated by significant correlations (.87 and .84 in the two samples) over several years between an earlier and revised form of the questionnaire. Validity was demonstrated via (a) correlations between the questionnaire score and reading measures (rs = .57-.70), (b) the results of a discriminant function analysis that used questionnaire scores to predict reading disability diagnosis, and (c) the finding that the questionnaire had substantial incremental validity in predicting reading skill in a hierarchical regression analysis that first entered IQ and SES. These results indicated that the questionnaire is both reliable and valid.

Spelling errors and reading fluency in compensated adult dyslexics.

Generally, a person who is diagnosed as dyslexic remains diagnosably dyslexic all his/her life. However, occasionally, an individual compensates for his/her difficulties in some way, and by adulthood is no longer diagnosably dyslexic. In what ways are these compensated dyslexics different from both dyslexics and nondyslexics? We compared IQ, achievement test, and spelling error scores in adult dyslexics, adult nondyslexics, and adult compensated dyslexics (N=25) in the two studies reported here. The second study differed from the first in that the subjects were matched for age, education, IQ, and SES. In both studies, compensateds were significantly different from nondyslexics on the WRAT Spelling subtest and Reading Quotient scores. In the second study the compensateds differed from the nondyslexics in total raw score and average reading speed on Gray Oral Reading Test. On the other hand, they were different from dyslexics on all reading and spelling variables in both studies, except for PIAT Reading Comprehension in Study 2. Finally, in Study 2, the compensateds were different from both dyslexics and nondyslexics in average reading speed. In conclusion, it appears that compensation does not result from differences in IQ, education, or SES, though it may be influenced to some extent by sex. Compensateds appear very similar to nondyslexics in their reading and spelling skills; however, there appears to be a difference in the automaticity with which they apply these skills.

Is phonology bypassed in normal or dyslexic development?

A pervasive assumption in most accounts of normal reading and spelling development is that phonological coding is important early in development but is subsequently superseded by faster, orthographic coding which bypasses phonology. We call this assumption, which derives from dual process theory, the developmental bypass hypothesis. The present study tests four specific predictions of the developmental bypass hypothesis by comparing dyslexics and nondyslexics from the same families in a cross-sectional design. The four predictions are: 1) That phonological coding skill develops early in normal readers and soon reaches asymptote, whereas orthographic coding skill has a protracted course of development; 2) that the correlation of adult reading or spelling performance with phonological coding skill is considerably less than the correlation with orthographic coding skill; 3) that dyslexics who are mainly deficient in phonological coding skill should be able to bypass this deficit and eventually close the gap in reading and spelling performance; and 4) that the greatest differences between dyslexics and developmental controls on measures of phonological coding skill should be observed early rather than late in development.None of the four predictions of the developmental bypass hypothesis were upheld. Phonological coding skill continued to develop in nondyslexics until adulthood. It accounted for a substantial (32-53 percent) portion of the variance in reading and spelling performance in adult nondyslexics, whereas orthographic coding skill did not account for a statistically reliable portion of this variance. The dyslexics differed little across age in phonological coding skill, but made linear progress in orthographic coding skill, surpassing spelling-age (SA) controls by adulthood. Nonetheless, they didnot close the gap in reading and spelling performance. Finally, dyslexics were significantly worse than SA (and Reading Age [RA]) controls in phonological coding skill only in adulthood.

Spelling errors in adults with a form of familial dyslexia.

We compared the spelling errors on the WRAT II made by adults (N = 24) with an apparent autosomal dominant form of dyslexia to those made by their normal adult relatives (N = 17) and by spelling-age matched normal controls (N = 17) using a computerized error evaluation program (SEEP). The normal adult relatives were significantly better than the dyslexics in both reading and spelling, but did not differ in age, education, or IQ. SEEP evaluated each error independently for both phonological and orthographic accuracy at 2 levels of complexity. Each level of complexity was analyzed separately using a 3 X 2 (group X dimension) analysis of variance. The main finding of interest was a significant group X dimension interaction effect at the complex level, which indicated that the dyslexics had a qualitatively different profile across the 2 dimensions than either normal group who had parallel profiles. The dyslexics performed like the younger normal group on the complex phonological dimension but like the adult normal group on the complex orthographic dimension. These results indicate a dissociation in this form of familial dyslexia between these 2 dimensions of spelling development, and suggest that these dyslexics may fit the subtype of dysphonetic or phonological dyslexia. The implications of these results for the underlying cognitive deficit in this form of dyslexia are discussed.