Evaluation of Speech Rhythm Training in Dyslexic Readers Aged 7 to 9 Years

Evaluation of Speech Rhythm Training in Dyslexic Readers Aged 7 to 9 Years

Studies of dyslexia have shown altered oscillatory activity in the low gamma band (~25-35 Hz) in the left auditory cortex. Neural oscillations around 30 Hz constitute the basic sampling rate of speech, from which the ability to form specific phonemic categories on which reading learning is based is derived. An alteration of the oscillatory activity at 30 Hz could therefore influence the ability of children to learn to read, and explain the reading deficit observed in children with a specific written language disorder. The objective of our study is to determine whether intensive rhythmic auditory stimulation applied during 30 sessions of 15 minutes spread over 6 weeks (5 sessions per week) can correct neural oscillations in the gamma-low band, allowing an improvement of phonemic categorization abilities, and thus the reading abilities of dyslexic readers aged 7 to 9 years. The long-term objective of this study is to test the therapeutic potential of auditory stimulation with speech rhythms for the treatment of reading disorders.

Longitudinal cross-over study carried out on 4 experimental groups to compare the effect of two rhythmic auditory trainings (30 Hz and low frequencies) compared to the effect of a grapho-phonological correspondence training (GraphoGame).

The study begins with a recruitment and inclusion period after diagnosis of dyslexia. During this study, 4 assessments are performed and include behavioral measures in the care setting and electrophysiological measures in the research setting:

• at time T1 before any remediation,
• at T2 after the first training,
• at T3 at most 7 days after the 2nd training session,
• at T4 seven weeks after T3.

After the T1 assessment, participants were randomized into 4 different groups (training 1 then training 2):

Group 1 : Auditory Rhythmic at 30 Hz then GraphoGame Group 2 : GraphoGame then Rhythmic Auditory at 30 Hz Group 3 : Auditory Rhythmic at low frequencies then GraphoGame Group 4 : GraphoGame then Auditory Low Frequency Rhythmic The first training period (total duration 6 weeks) according to the assigned group begins and takes place at the speech therapist's office and at home.

After the T2 evaluation, the 2nd training period (total duration 6 weeks) according to the assigned group begins and takes place at the SLP's office as well as at home.

The post-training evaluations T3 and T4 take place, respectively, 1 week and 7 weeks after the last training.

Inclusion Criteria:

• between 7 and 9 years old
• in regular schooling
• have a diagnosis of dyslexia
• have a non-verbal intelligence assessment within the norm. Inclusion assessments must show a major reading disability without associated cognitive deficits.
• be equipped with a PC at home
• have given their assent and whose parents/legal guardians have given their oral consent

Exclusion Criteria:

• have any other diagnosis of language impairment
• have a neurological disorder (visual, auditory, executive)
• have an associated psychiatric disorder
• have a developmental delay.