Approximately 200 families have been recruited to the study during the years 2015–2017. In families where one or both parents have reported having dyslexia, the parents have been tested for their reading skills. The participating families have been divided into subgroups based on their dyslexia status. Additionally, a randomly selected sample of the families has been given sound material that they should play to the infant at home during the first six months (listening intervention).
In the first phase of the experiment, the newborn infant participates in an electroencephalogram (EEG) recording. The measurement is safe, fast, and painless, and it is globally used in clinical settings. During the recording, electrodes that register electric activity from the brain are attached to the surface of the scalp, and the infant is presented with sounds. The infant can sleep throughout the study. The study gives us information on the auditory skills of the infant, but the results are not reliable at the individual level. The infant and the parents also provide samples of saliva or blood, in order to extract the DNA and, specifically, genes related to dyslexia.
At six months, the listening intervention ends. Some families are invited to participate in a second infant EEG recording. Unlike the newborns, six-month-olds are awake and sitting during the recording.