Subjective and objective evaluation of visual functions in dyslexic children with visual perceptual deficiency—Before and after ten-weeks of perceptual training

Ka Yan Leung, Henry Ho Lung Chan, Mei Po Leung

Research output: Journal article publicationJournal articleAcademic researchpeer-review

3 Citations (Scopus)


Aims: This pilot study investigated perceptual and electrophysiological characteristics of dyslexic children, and evaluated the immediate and prolonged effect of visual perceptual training on these characteristics in these children. Methods and procedures: Seven dyslexic children and seven controls aged 7–8 years were recruited and completed this study. All dyslexic children completed 10-weeks of visual perceptual training. The visual perceptual skills were assessed and binocular visual evoked potentials (VEP) were recorded with two different pattern stimulations initially (Baseline), 3 months after the first assessment (Evaluation I) and 6 months after first assessment (Evaluation II). Outcomes and results: A significant reduction (p = 0.021) in VEP amplitudes in the dyslexic subjects in response to 15 Hz reversal frequency at 15% contrast stimulation was found, compared with controls, prior to perceptual training. A significant correlation (p = 0.005) was found between the VEP amplitude with 15 Hz reversal frequency and the total score of Test of Visual Perceptual Skills (non-motor) – revised (TVPS-R). After training, dyslexic subjects scored higher in some of the visual perceptual tasks and these improvements persisted for 3 months. However, the VEP amplitude in the dyslexics showed no significant change after perceptual training.

Original languageEnglish
Pages (from-to)112-130
Number of pages19
JournalResearch in Developmental Disabilities
Early online date6 Jul 2018
Publication statusPublished - Sept 2018


  • Dyslexia
  • Perception
  • Perceptual training
  • Visual evoked potential
  • Visual perceptual deficiency
  • Visual perceptual skills

ASJC Scopus subject areas

  • Developmental and Educational Psychology
  • Clinical Psychology

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