Unusual brain oscillations in people with dyslexia may impair their ability to process speech.
When learning to read, children must match their own mental representations of speech sounds with universal ones that correspond to letters. While this is a simple process for most, some experience difficulties because the sounds they have in mind have a slightly atypical format.
University of Geneva researcher, Professor Anne-Lise Giraud, has discovered that oscillations in the brains of people with dyslexia are not at the correct frequency or in the correct location in the brain, which has consequences for the way they break speech down into chunks of elementary sounds.
Using training and a new method of external brain stimulation, known as transcranial alternating current stimulation, this Wyss Center supported project will repair disrupted neural pathways in order to reorganize brain rhythms so that signals are properly processed, potentially solving the problems of dyslexia.
The goal is to develop an algorithm and a device to enable this training and then carry out clinical trials to demonstrate its effectiveness in dyslexia sufferers.
Having shown that the auditory cortex of people with dyslexia produce neural oscillations at a slightly higher frequency than normal-readers, and therefore sample speech slightly too fast, it was tempting to try to correct this dysfunction with transcranial electrical stimulation.Professor Anne-Lise Giraud
University of Geneva
Professor Anne-Lise Giraud: “Our goal is to exploit our knowledge about the neural computations in the auditory cortex, to repair neurodevelopmental language disorders that have an established auditory component, typically dyslexia and autism.
“Having shown that the auditory cortex of people with dyslexia produce neural oscillations at a slightly higher frequency than normal-readers, and therefore sample speech slightly too fast, it was tempting to try to correct this dysfunction with transcranial electrical stimulation.
“We are currently studying the impact of such a minimally invasive, targeted, intervention on phonological and reading skills in adults, before considering an application to dyslexia in children.”
This same approach might also in the future help people with autism to cope better in speech communication situations.
We are seeking adults with dyslexia to take part in our experiment. If you would like to find out how to get involved please contact Silvia Marchesotti.