[Early detection of autism spectrum disorders: emerging symptoms and biomarkers].

Early recognition of Autism Spectrum Disorders (ASD) in patients before the age of 24 months significantly enhances the prognosis of affected children. That's why researchers try to identify behavioral and/or neurophysiological precursors in the first months of life of children. Prospective studies are specifically performed in infant siblings at risk of ASD. The longitudinal high-risk sibling studies of ASD follow a cohort of children with an older sibling already diagnosed with ASD. Of these, 10-20% will be diagnosed with ASD during their third year. This review aims to summarize the clinical and neurophysiological studies investigating early markers associated with the emergence of autistic symptoms in children.