Language Development Deficits and Early Interactive Music Intervention

Inclusion Criteria: * 8-12 months old at start of intervention (recruited between 0-11 months) * Born healthy and at term (gestational age at least 37 weeks and birth weight at least 2500 g) * Normal hearing at birth (evoked oto-acoustic emissions conducted to newborns routinely at the hospital) * At least one caregiver living with the child is native speaker of Finnish and speaks Finnish to the child * Risk group: At least one biological parent has developmental dyslexia according to a recent (\<5 years) diagnostic statement by a health care professional or according to a dyslexia test at study enrollment; symptoms have started in childhood Exclusion Criteria: * Medication affecting the central nervous system * Sensory deficits * Serious health conditions * No-risk group: Suspected dyslexia or developmental language disorder due to symptoms that have started in childhood in either of the biological parents; diagnosis of a developmental or language disorder (incl. dyslexia, developmental language disorder, attention-deficit/hyperactivity disorder ADHD, attention-deficit disorder ADD) or neurological disorder in either of the biological parents * Risk group: Diagnosis of ADHD, ADD, or other not-language-related developmental disorder in either of the biological parents; in the dyslexic parent, brain trauma in childhood that may indicate a non-heritable cause for the reading deficit or individualized school curriculum that may indicate broader developmental deficits.