Limited Visual Working Memory Capacity in Children with Dyslexia: An ERP Study

  • Salahadin Lotfi University of Wisconsin-Milwaukee
  • Richard T Ward Department of Psychology, University of Wisconsin – Milwaukee, USA
  • Abel S. Mathew University of Wisconsin-Milwaukee
  • Mohsen Shokoohi-Yekta Faculty of Psychology and Education, University of Tehran, Iran
  • Reza Rostami Faculty of Psychology and Education, University of Tehran, Iran
  • Negin Motamed-Yeganeh
  • Christine L. Larson
  • Han-Joo Lee
Keywords: working memory, n-back, oddball, dyslexia, P300 event-related potentials (ERP)


Some researchers suggest that deficits in attention and working memory influence the development of dyslexia, whereas others propose that these deficits are more likely due to reduced global processing speed. The current study aimed to investigate behavioral performance in children with dyslexia compared to typically developing controls on two tasks: a visual oddball task for attention and an n-back task for working memory. We measured P300 event-related potentials (ERP) amplitude and latency for both tasks. Our results demonstrated reduced behavioral accuracy and P300 amplitude for the children with dyslexia compared to their typically developing peers in both the n-back and visual oddball tasks. We also found no differences in response time or P300 latency between these groups on either task. These findings support the idea that children with dyslexia experience deficits in cognitive processes related to working memory and attention, but do not exhibit decreased global processing speed on these tasks.


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