LAUSR

Purpose of review To analyze the interrelated factors that have led to the striking increase in functional movement disorders in recent years, with a focus on functional tic-like behaviours (FTLB). Recent findings The sudden onset of FTLB has been widely observed in several countries since the beginning of the SARS-CoV-2 pandemic, whereas it was previously very rarely reported. Pandemic-related FTLB typically occur in young females, share complex, disabling and tic-lookalike patterns, and are usually triggered by the exposure to videos portraying tic-like behaviours on social media. Both pandemic-related FTLB and prepandemic FTLB are associated with high levels of depression and anxiety. FTLB related to the pandemic highlight the role of social media in the psychopathological behaviours of our time. Summary We suggest FTLB are due to a combination of predisposing factors (high genetic and epigenetic risk for anxiety and depression, negative past experiences) and precipitating factors (pandemic and its impact on mental health, exposure to certain social media content). These factors of vulnerability may increase the risk of developing behavioural and emotional problems in youth, such as FTLB. Early diagnosis and appropriate treatment of psychiatric comorbidities seem to be predictors of positive prognosis.