What Do We Currently Know About Functional Tic-Like Behaviors: A Topical Review

Background: During the last 5 years, functional tic-like behaviors (FTLBs) have been the center of an increasing amount of scientific research. Purpose: The purpose of this review was to collect this research and create an overview of what is currently known about the patient group. Methods: PubMed, EMBASE, and Web of Science were systematically searched for relevant papers, which were then sorted based on set inclusion and exclusion criteria. This process resulted in twenty-four papers selected for extraction, the results of which were summarized. Results: The results were split into three topics: characteristics, follow-ups, and treatment. Across studies on characteristics, patients with FTLB have overall higher symptom severity and complexity and a higher prevalence of anxiety and depression compared to the patients with Tourette syndrome included in the studies. The patients with Tourette syndrome had a higher prevalence of simple tics and comorbid attention-deficit/hyperactivity disorder and obsessive-compulsive disorder. However, in both populations there was considerable heterogeneity in both comorbidity profile as well as the characteristics of vocalizations and movements. The follow-up literature was relatively small but showed a general reduction in FTLB patients’ symptoms over time, although spontaneous remission was rare. The treatment literature, which consisted of just two articles, showed good benefit of cognitive therapies. Conclusions: Overall, the FTLB patient group presents with a wide variety of symptoms, which tends to persist but responds well to cognitive treatment. More research is needed particularly within the treatment literature.