Reading ability and processing in Duchenne muscular dystrophy and spinal muscular atrophy

Abstract

Duchenne muscular dystrophy (DMD) is a fatal recessive X-linked muscular disease affecting about 1 in 3500 live-born human males, characterized by severe muscle degeneration and responsible for muscular weakness. *Correspondence to first nictbor at address nbotieWe analysed the reading avities and processing of 21 children.with Duchenne muscular dystrophy (DMD), 11 matched children suffering from spinal muscular atrophy (SMA) and 42 children receiving normal education. The principal result observed was that the DIM) children exhibited a reading age which was siWcantly lower than the SMA children compared with their chronological age. These learning disabilities were not related to adeficit in non-verbal performance intelligence, but psycholinguistic evaluation Simildties and Arithmetic WISO-R subtests, in phonological abilities, oral word repetition, and in digit span score. The results for the DWD children were heterogeneous, and-ranged from normal to greater or lesser involvement. X n an attempt to c l a m the nature of this reading impairment in DMD children, the three groups (DMD, SMA, and normal control children) were tested by reading aloud a list of single words and non-words. The DMD children were significantly impaired in r e e g non-words, suggesting reading disability to dysphonetic dyslexia, the most freqbent subtype of developmental'dyslexia. These results are discussed in the light of psychometric data available for our DMD population and in the light of previous studies. The practical consequenees of diagnosis on rehabilitation are very important. The precise description of the cognitive deflcits seen in DMD js of value for futpre clinical and genetic studies.

Verbal and memory skills in males with Duchenne muscular dystrophy

“…Single-word comprehension has been shown to be strong, 8,9,17 as has single word expression or picture naming, 6,9 although it is lower in younger children with DMD. 18 Some studies have demonstrated impaired verbal fluency, 8,17,19,20 whereas others do not; 6,9 the differences are probably due in part to impaired letter or phonemic fluency and intact category or semantic fluency.…”

“…18 Some studies have demonstrated impaired verbal fluency, 8,17,19,20 whereas others do not; 6,9 the differences are probably due in part to impaired letter or phonemic fluency and intact category or semantic fluency. Tests of syntactic comprehension have shown compromised skills in some studies 9,17 but not in others 6 (although we have argued that poor performance was due less to not understanding grammatical rules than to the verbal load of the tasks, thus implicating immediate verbal span 9 ).…”

“…4,[6][7][8] Specific findings included lowered scores on Digit Span, Arithmetic, Similarities, Word Repetition, Supraspan, and Reading tests. Other areas, including many measures of basic language skill and nonverbal abilities, were not different between the two groups, highlighting the selective nature of the cognitive profile.…”

“…2,3 As a group, children with DMD present with relatively weak verbal and immediate memory skills. [4][5][6][7][8] There is individual variation across factors that contribute to the cognitive phenotype, including intellectual level, age, degree of physical disability, and background environment. The goal of the present study was to explore, in detail, language and verbal memory skills in children with DMD.…”

Psychophysical measurements of luminance and chromatic spatial and temporal contrast sensitivity in Duchenne muscular dystrophy.

“…Children with DMD also have mental impairment, reflected in borderline or reduced scores in the full intelligence quotient and visuospatial tests (Wicksell, Kihlgren, Melin, & Eeg-Olofsson, 2004), visuomotor impairment (Marsh, 1972;Mehler, 2000), a reduction in verbal ability (Bresolin et al, 1994), and impairment in reading ability (Billard, Gillet, Barthez, Hommet, & Bertrand, 1998). Improvements in respiratory management and pharmacological drugs have increased the life expectancy of DMD children by almost a decade.…”