Functional neurological disorders (FND) in childhood and adolescence: clinical pathways, prognostic factors, and the role of time

Functional Neurological Disorder (FND) represents a complex clinical category at the interface between neurology and psychiatry. It is increasingly understood as a disorder of brain functioning rather than structural pathology, arising from abnormal predictive coding and altered integration of emotional, cognitive, and motor control systems. Despite growing recognition in adults, evidence on developmental FND remains limited. This doctoral thesis investigated FND in childhood and adolescence through three complementary empirical studies addressing diagnostic, comparative, and prognostic aspects, with the overarching aim of outlining a multidimensional and developmentally informed framework. The first study focused on Functional/Dissociative Seizures (FDS) and evaluated the diagnostic utility, safety, and feasibility of a structured Standardized Suggestive Seizure Induction Technique (SSIT) protocol integrated into video-EEG monitoring. In a cohort of 25 pediatric patients, SSITs reproduced habitual functional seizures in over 50% of cases, without adverse events, supporting their value as transparent and ethically acceptable diagnostic procedures in child and adolescent settings. The second study provided a comparative analysis between FDS and Functional Motor Disorders (FMD) in 43 young patients. Despite different outward phenomenology, both groups shared overlapping neuropsychological and psychopathological features, including mild inefficiencies in working memory, elevated anxiety, and dissociative tendencies, consistent with transdiagnostic mechanisms of impaired emotion-action integration. The third study examined prognostic determinants and healthcare pathways in pediatric FMD, highlighting the critical role of early recognition and coordinated multidisciplinary treatment. Shorter diagnostic latency and integrative rehabilitation were associated with improved recovery, emphasizing the importance of timing as a determinant of clinical outcome. Taken together, these findings contribute to a unified developmental model of FND, bridging neurobiological, psychological, and systemic perspectives. The thesis underscores the need for early, interdisciplinary, and person-centered approaches, promoting functional restoration through timely intervention and collaborative care.