What Do We Know about Early Onset Neurodevelopmental Disorders?

Early onset neurodevelopmental disorders include a broad range of conditions that affect brain function in children: different diagnostic categories such as fetal alcohol syndrome, attention-deficit/hyperactivity disorder, intellectual disability, and autism spectrum disorders. Combined, they affect more than 10% of all children, and some disabilities are permanent throughout their lifetime. Causes are heterogeneous ranging from social deprivation, genetic and metabolic diseases, immune disorders, infectious diseases, nutritional factors, physical trauma, and toxic and environmental factors. Treatments often involve a combination of professional therapy, pharmaceuticals, as well as home- and school-based programs. This chapter briefly reviews the biological pathways associated with early onset neurodevelopmental disorders and provides useful links to progress in the field. Five main biological pathways are associated with autism spectrum disorders and intellectual disability: chromatin remodeling, cytoskeleton dynamics, mRNA translation, metabolism, and synapse formation/function. Three propositions to foster research, proposed by institutions, researchers, and the community of patients and families, will be discussed: (a) to use more dimensional and quantitative data than diagnostic categories; (b) to increase data sharing and research on genetic and brain diversity in human populations; and (c) to involve patients and relatives as participants in research. Finally, examples are provided of very stimulating initiatives toward a more inclusive world of individuals with neurodevelopmental disorders.