AUTHOR=Graziola Federica , Pellorca Chiara , Di Criscio Lorena , Vigevano Federico , Curatolo Paolo , Capuano Alessandro 

TITLE=Impaired Motor Timing in Tourette Syndrome: Results From a Case–Control Study in Children

JOURNAL=Frontiers in Neurology

VOLUME=Volume 11 - 2020

YEAR=2020

URL=https://www.frontiersin.org/journals/neurology/articles/10.3389/fneur.2020.552701

DOI=10.3389/fneur.2020.552701

ISSN=1664-2295

ABSTRACT=Tourette syndrome is a neurodevelopmental disorder characterized by motor and vocal tics. Co-occurrence of Attention deficit and hyperactivity disorder (ADHD) or Obsessive Compulsion Disorder (OCD) is very frequent in pediatric population as well as the presence of an impairment of the executive functions. The aim of our study was to investigate motor timing that is the temporal organization of motor behaviour, in a paediatric population of Tourette patients.  Thirty-seven Tourette patients (divided in 22 “pure” Tourette patients and 15 with ADHD) were compared with 22 healthy age- and gender matched subjects. All subjects underwent a neuropsychiatric screening and were tested for their planning and decision-making abilities by using a standardized test as Tower of London. Two experimental paradigms were adopted: finger tapping test, a free motor tapping task, and the synchronization-continuation task. An accuracy index was calculated as measure of ability of synchronization. We found that “pure” TS as well as TS+ADHD showed lower scores in the finger tapping test for the dominant and non-dominant hand, compared with controls. Moreover, in the synchronization and continuation test, we observed an overall lack of accuracy in both TS groups in the continuation phase for 2000 ms (supra-second interval), interestingly, with opposite direction of accuracy index. Thus, “pure” TS patients were classified as “behind the beat”, whereas TS+ADHD as “ahead of the beat”. The performance in the finger tapping was inversely correlated to Tower of London total scores and execution time; while we did not find any correlation with the accuracy index of the synchronization and continuation test. In conclusion, here, we explored motor timing ability in a childhood cohort of Tourette patients confirming that patients exhibit an impaired temporal control of motor behavior and these findings may be explained by the common underlying neurobiology of Tourette syndrome and motor timing.