1. Institute of Neurological Sciences, National Research Council, Catania, Italy
2. Unit of Rare Diseases of the Nervous System in Childhood, Department of Clinical and Experimental Medicine, Section of Pediatrics and Child Neurospychiatry, University of Catania, Catania, Italy
3. Section of Psychology, Department of Educational Sciences, University of Catania, Catania, Italy
4. Department of Medical and Surgical Sciences and Advanced Technology “G.F. Ingrassia,” University of Catania, Catania, Italy
5. Unit of Pediatrics, Lentini Hospital, Lentini, Italy
6. Unit of Pediatrics, Carpi Hospital, Carpi, Italy
7. Division of Medical Genetics, Department of Biomedical Sciences and Human Oncology (DIMO), University of Bari “Aldo Moro,” Bari, Italy
8. Maurice Wohl Clinical Neuroscience Institute, King's College London, London, United Kingdom