Neurofunctional Correlates of the Behavioral Modifications Associated With Tachidino in Children With Developmental Dyslexia (TACHIDINO)

Neurofunctional Correlates of the Behavioral Modifications Associated With Tachidino in Children With Developmental Dyslexia

Neurofunctional Correlates of the Behavioral Modifications Associated With Tachidino in Children With Developmental Dyslexia

Developmental dyslexia (DD) is the most common learning disorder. Multiple cognitive and sensory domains contribute to the etiology of DD and develop before reading acquisition. Atypical brain functional responses and structural features have been found in the reading developing circuitry. Treatments addressing visual-spatial attention and motion perception (Visual Attention Training; VAT) are among the most effective interventions in Italian children with DD. The VAT seems to improve the efficiency of the visual attention system and the magnocellular (M) pathway which is crucial for learning to read. Evidence for impaired M function in subjects with DD in the visual striate and extra-striate cortex have been reported. How these treatments affect the brain functionality is still not clear. Since DD has a neurobiological basis, it is important to deeply investigate atypical functional responses and structural features in reading-related areas, and to understand how treatments operate at the neuronal level. A growing number of studies investigates structural and functional measures in neurodevelopmental disorders by using high-resolution MRI at high field (3T and 7T). Similarly, several studies examine the effects of different types of reading training upon brain activity. Better understanding of the relationship between structural/functional abnormalities and DD could disentangle the causes of reading difficulties and helps in developing effective treatments. The significance of this study is twofold: 1) NEURAL CORRELATES OF TREATMENT: The investigators expect TACHIDINO to specifically affect the underlying neurophysiological functioning which influences reading skills in children with DD; 2) BRAIN SIGNATURES: As integrated multi-domain data (behavioral and brain imaging) are complementary to each other, they could enhance the possibility to find unique treatment/brain functioning combinations to evaluate the effectiveness of intervention and to predict the treatment response.

TACHIDINO is based on two principles a) selective stimulation of a cerebral hemisphere and specific reading strategies, and b) the training of selective visuospatial attention, as well as the perception of rapid movement and the visual characteristics of words even in the presence of so-called visual crowding or "crowding", an automatic effect of our perceptual system that leads to "obfuscation" of the visual areas surrounding the object to be analyzed, to make its vision clearer (as suggested by the "Magnocellular theory" of dyslexia; Stein et al., 2019).

Inclusion Criteria: Reading skills (both accuracy and speed) below -2.00 standard deviation Exclusion Criteria: No ADHD No contraindications to magnetic resonance