Evaluation of phonological processing skills of young children
with neuroﬁbromatosis type 1
HEATHER L THOMPSON
Department of Communication Sciences and Disorders, California State
University, Sacramento, Sacramento, CA, USA.
This commentary is on the original article by Arnold et al. on pages
703–710 of this issue.
Speciﬁc learning disability (SLD) is characterized by deﬁcits
in one or several processes needed for understanding or
using language, and includes the diagnosis of language
learning disability or dyslexia (a reading disability subtype).
Populations most at-risk for SLD include those with a his-
tory of speech sound disorder and receptive/expressive lan-
guage delay, and concerns with either phonological
processing or oral language comprehension.
children with SLD can initially present with problems in
word pronunciation, rhyming, word-ﬁnding, and/or follow-
ing directions, and may obtain a diagnosis of speech sound
disorder or language impairment. Children with speech
sound disorder characterized by the use of phonological pat-
terns may have poor or inaccurate underlying phonological
representations. As the demands of the educational curricu-
lum increase, difﬁculties in speech/language use may persist,
with children subsequently securing a diagnosis of reading
disability in the later elementary school years.
In the preschool years, children with the neurocutaneous
genetic disorder neuroﬁbromatosis type 1 (NF1) may exhi-
bit delays in speech and/or language. Approximately 30%
to 65% of school-aged children with NF1 exhibit SLD.
Currently, the nature of SLD in NF1 is unclear. Learning
disability subtypes have varied across studies, depending on
the populations included or the models or proﬁles utilized
in the investigations. Hyman et al.
evaluated 81 children
with NF1 and found that 52% exhibited learning disability;
32% exhibited general learning disability, 8.6% exhibited
reading disability, 8.6% exhibited spelling disability, and
9.9% exhibited mathematical disability (dyscalculia). Watt
evaluated 30 children with NF1 and found reading
concerns in 67%; 75% of whom exhibited phonological
dyslexia and 20% of whom exhibited mixed dyslexia.
Orraca-Castillo et al.
evaluated 32 children with NF1 and
found SLD in 53.1%; dyslexia occurred in 50%, and
dyscalculia occurred in 18.8%. Differences in auditory pro-
cessing or functional cortical activity during phonological
processing may contribute to SLD in this population.
There is a need to evaluate the relationship between pre-
literacy and spelling abilities in 5- to 6-year-old children
with NF1 to elucidate possible precursors to SLD. As
Arnold et al.
suggest, deﬁcits in phonological awareness,
phonological memory, and letter-sound knowledge in young
children with NF1 may play a role in how phonological
information is stored and subsequently retrieved when
decoding during reading and spelling. It is likely that phono-
logical processing and deﬁcits in phonics may account for
later SLD in children with NF1.
Arnold et al. are to be commended for conducting a
study aimed at further characterizing the pre-literacy skills
of young children with NF1. The nature of the investiga-
tion is timely given our knowledge of SLD in NF1.
Results of the study support future clinical practice and
the need for early assessment of phonological processing
and phonics skills of young children with NF1. For chil-
dren with identiﬁed concerns, timely follow-up with a
speech-language pathologist is indicated. If speech-lan-
guage concerns are remediated by the time children are
approximately 5½ years of age, literacy skills can develop
fairly normally for those without NF1. Children without
NF1 who exhibit speech sound disorder or language
impairment have also shown improvements in response to
phonological awareness intervention. Future research
should investigate the effectiveness of speech-language
intervention for young children with NF1 in this at-risk
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642 Developmental Medicine & Child Neurology 2018, 60: 636–644