Blog Summary 8: Down's Syndrome and Nonword Repetition Test

Responses are due on Monday, Feb. 9th
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The Use of Nonword Repetition as a Test of Phonological Memory in Children with Down Syndrome


Recent research suggests a significant relationship between verbal short-term memory and normal language development. Poor short-term memory and impaired language are features of Down Syndrome.

This study report the use of nonword repetition with 33 children and teenagers with Down Syndrome aged from 5-18 years, and investigates the relationship between this test and other memory and language measures.

Nonword repetition was significantly correlated with age, and when age and nonverbal cognitive ability were controlled, nonword repetition was significantly correlated with all other language-based memory measures, i.e. auditory digit span, word span, sentence repetition, and fluency, and also with memory for a sequence of hand movements, but not with memory for faces or a visual digit span task.

Down Syndrome, or trisomy 21, is the most common cause of learning disability, affecting an estimated 1/700 to 1/1000 live births. (Hassold & Jacobs) Besides physical appearance a number of other features are associated with the syndrome such as language impairment (Rondal), language development and dissociation within the language system (Fowler & Lenneberg).

There has been considerable research to investigate the memory deficit itself. One way to think of it is with a working memory model created by Baddeley and Hitch. The model includes the notion of separate systems for the processing of visuo-spatial material and verbal material.

The main focus of research on memory in Down Syndrome has thus been on the description of syndrome-specific deficits, the investigation of possible causes, such as a lack of rehearsal, or the remediation of these memory problems.

Hulme and Mackenzie hypothesize that language problems lead to memory problems that, in turn, affect skills such as reading comprehension. In normal development, individual differences in short term memory capacity correlate with reading ability. Findings suggest that learning to read may lead to improved auditory and visual memory skills as well as better vocabulary understanding and language comprehension.

By Lara Nederveen Pieterse