Dyslexia with and without Irlen syndrome: A study of influence on abilities and brain‐derived neurotrophic factor level

Abstract

The presence of comorbid Irlen syndrome (IS) in children with developmental dyslexia (DD) may have an impact on their reading and cognitive abilities. Furthermore, the brain‐derived neurotrophic factor (BDNF) was reported to be expressed in brain areas involved in cognitive and visual processing. The aim of this study was to evaluate some cognitive abilities of a group of dyslexic children with IS and to measure and compare the plasma BDNF level to dyslexic children without IS and neurotypical (NT) children. The participants were 60 children with DD (30 in the DD + IS group; 30 in the DD group) and 30 NT children. The Irlen reading perceptual scale, the Stanford Binet intelligence scale, 4th ed, the dyslexia assessment test, and the Illinois test of psycholinguistic abilities were used. The BDNF level was measured using the enzyme‐linked immunosorbent assay. One‐minute writing and visual closure deficits were more prevalent, while phonemic segmentation deficits were less prevalent in the DD + IS group compared to the DD group. The BDNF level in the DD groups was lower than that in NT children (p < 0.001). Some reading and non‐reading tasks were influenced by the presence of a coexisting IS. The reduced BDNF level could play a role in the deficits noticed in the abilities of children with DD.

Comprehensive mapping of the AOP-Wiki database: identifying biological and disease gaps

“…Most importantly, KE ID 381 represents the brain-derived neurotrophic factor (BDNF), a key molecule necessary for healthy brain development and notably its learning and memory function. The dysregulation of BDNF was linked with numerous NDDs such as Autism Spectrum Disorder (ASD, ICD-11 6A02) (Liu et al, 2021), dyslexia (ICD-11 6A03) (Abdelraouf et al, 2023) and intellectual disability (ICD-11 6A00) (Esnafoglu and Adıgüzel, 2021), but not with Attention Deficit Hyperactivity Disorder (ADHD, ICD-11 6A05) (Mei et al, 2022;de Lucca et al, 2023). ADHD was, on the other hand, associated with impaired synaptogenesis (KE ID 385) (Dark et al, 2018;Halperin et al, 2021).…”