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bioRxiv · 10.1101/2020.03.25.008169

Capacity of short-term memory in dyslexia is reduced due to less efficient utilization of items' long-term frequency

Kimel, E.·Ahissar, M.·Lieder, I.
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Abstract

Dyslexia, defined as a specific impairment in decoding the written script, is the most widespread learning difficulty. However, individuals with dyslexia (IDDs) also consistently manifest reduced short-term memory (STM) capacity, typically measured by Digit Span or non-word repetition tasks. In this paper we report two experiments which test the effect of item frequency and the effect of a repeated sequence on the performance in STM tasks in good readers and in IDDs. IDDs performance benefited less from item frequency, revealing poor use of long-term single item statistics. This pattern suggests that the amply reported shorter verbal spans in dyslexia may in fact reflect their impaired sensitivity to items long-term frequency. For repeated sequence learning, we found no significant deficit among IDDs, even when a sensitive paradigm and a robust measure were used.

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Kimel, E., Ahissar, M., Lieder, I.. 2020-03-26. Capacity of short-term memory in dyslexia is reduced due to less efficient utilization of items' long-term frequency. https://doi.org/10.1101/2020.03.25.008169

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