Developmental Dyslexia and Remediation Methods
Condition: Dyslexia, Developmental
MeSH terms: Dyslexia
Study type: Interventional

Summary: 
      At least, three theoretical frameworks are currently involved in therapeutic research in
      developmental dyslexia. Each theoretical framework relies on the type of underlying cognitive
      processes that is viewed as impaired: 1°) phonological processing, 2°) cross modal
      integration, 3°) visual attention processing. In this controlled and randomized study, three
      types of computerized training are combined in a multi-factorial remedial approach in 8 to 12
      year old children with dyslexia. The main objective is to compare the effectiveness of this
      remedial approach which combines phonological, visual-attentional and cross-modal training
      with conventional non-intensive and non-specific rehabilitation
    

Detailed description: 
      Developmental dyslexia is defined as a specific and lasting reading learning disorder. This
      neurodevelopmental disorder has a severe impact on overall academic learning and behavior,
      compromises professional and social development and affects 10% of school-age children. As a
      public health problem, its diagnosis and management are still highly controversial, and the
      lack of scientific consensus leads to great heterogeneity in clinical practices and
      post-treatment outcomes. Three therapeutic axes guide research for developmental dyslexia.
      The first axis is based on phonological deficits. According to the phonological
      representation hypothesis, a specific deficit in the processing of phonological
      representations that support the identification of sounds is the cause of the reading
      disorder. The second axis focuses on attention-related cognitive deficits. According to the
      visuo-attention deficit hypothesis, a lack of the visuo-attention processing can be viewed as
      one of the explanatory causes of a dysfunction in letter identification and reading
      procedures. The third axis aims to achieve automatized processing for letter/sound
      association. According to the axis, a lack of cross-modal integration in word decoding is
      altered by a lack of simultaneous association between of a visual and an auditory stimulus.

      Many studies attempted to exclusively validate selective remediation according to causal
      hypotheses that are mainly cross-modal, phonological or visuo-attentional. However, the
      evaluation of these underlying processing in dyslexic children shows great clinical
      heterogeneity since most of children simultaneously have the three deficits. Furthermore, no
      study evaluates the benefits of combining these different trainings on reading skills.

      In this controlled and randomized study, three types of computerized training are combined in
      a multi-factorial remedial approach in 8 to 12 year old children with dyslexia. The main
      objective is to compare the effectiveness of this remedial approach which combines
      phonological, visual-attentional and cross-modal training with conventional non-intensive and
      non-specific rehabilitation.

      The secondary objectives will be 1°) to compare the effectiveness on reading skills of a
      phonological training, versus a visuo-attentional training, 2°) to compare the effectiveness
      on reading skills from in the order of phonological and visuo-attentional training, 3°) to
      compare the evolution of performance in comprehension and written production at the end of
      the three training sessions and 4°) to evaluate child and parents' perception for the outcome
      of the reading disorder at the end of the training sessions using Likert scales, by means of
      a questionnaire. The analysis of the results will make possible to evaluate a remedial
      approach to dyslexia in a clinical context and to better understanding and management of
      written language disorders.
    

Intervention name(s): Phonological; Visual-attention
Intervention type(s): Other; Other
Intervention description(s): Phase 1: intervention without targeted daily training (30 minutes/ week, for 8 weeks)
Phase 2: intervention with targeted daily training
Phonological training (15 minutes/ day, 5 days/week, for 8 weeks)
Visuo-attentional training (15 minutes/ day, 5 days/week, for 8 weeks)
Cross-modal training (15 minutes/ day, 5 days/week, for 8 weeks)
Phase 3: stopping training sessions for 8 weeks; Phase 1: intervention without targeted daily training (30 minutes/ week, for 8 weeks)
Phase 2: intervention with targeted daily training
Visuo-attentional training (15 minutes/ day, 5 days/week, for 8 weeks)
Phonological training (15 minutes/ day, 5 days/week, for 8 weeks)
Cross-modal training (15 minutes/ day, 5 days/week, for 8 weeks)
Phase 3: stopping training sessions for 8 weeks
Allocation: Randomized
Intervention model: Crossover Assignment
Masking: Single (Participant)
Primary purpose: Other