2019/09/25 by Christos Ganos, Davide Martino, Alberto J. Espay +3 · 4 citations
Psychology · Medicine · Neuroscience · #Obsessive-Compulsive Spectrum Disorders #Psychosomatic Disorders and Their Treatments #Botulinum Toxin and Related Neurological Disorders #Tics #Psychology #Context (archaeology) #Neuroscience #Movement disorders #Deep brain stimulation #Physical medicine and rehabilitation #Cognitive psychology #Functional movement #Medicine #Parkinson's disease #Disease
paper · doi:10.1212/wnl.0000000000008372
openalex publication_date 2019/09/25 · openalex created_date 2019/10/03 · openalex updated_date 2026/07/30
Within the broad spectrum of movement disorders, tics and functional tic-like movements belong to a particular clinical category. Both types of movements are within the range of normal movement kinematics and muscle synergies, but appear repetitive and without appropriate context embedment. Historically, there have been many attempts to separate the 2 types of movements, but because of their phenomenological overlap, clinical distinction may be prone to error, and misdiagnoses may often occur. Most importantly, the 2 types of movement may coexist. Here, we review the available literature on the 2 types of motor phenomena and demonstrate some of the difficulties in distinguishing tics from functional tic-like movements on clinical grounds. We also highlight similarities and differences in pathophysiologic characteristics, documenting the significance of action monitoring, attentional allocation, and behavioral reinforcement in both types of movements, as well as in their risk factors. We discuss the overlap of current behavioral treatments for tics and functional tic-like movements and emphasize implications of diagnostic mislabeling. Such implications include the need to tailor behavioral treatment approaches to individual phenomenological profiles and guiding decision making for severe patients requiring invasive interventions, such as deep brain stimulation. A deeper insight from clinicians with respect to persisting challenges in classifying and differentiating these motor phenomena could accelerate the development of reliable clinical and physiologic markers (i.e., next generation phenotyping) and a neurobiology-driven therapeutic approach for these motor phenomena.