1. Child & Adolescent Neuropsychiatry Unit, Department of Biomedical Sciences, University of Cagliari, & “G. Brotzu” Hospital Trust, Cagliari, Italy.
2. Funding: The authors received no specific funding.
3. Division of Child Neurology and Psychiatry, Department of Paediatrics, University of Messina, Messina, Italy.
4. Department of Clinical and Experimental Medicine, University of Messina, Messina, Italy.
5. Department of Cognitive Psychological Pedagogical Sciences and Cultural Studies, University of Messina, Messina, Italy.
6. Autism Research Unit, Villa Santa Maria Foundation, Tavernerio, Italy.