Related Experiment Video
Updated: Nov 30, 2025
Generating Acute and Chronic Experimental Models of Motor Tic Expression in Rats
Published on: May 27, 2021
Impaired Motor Timing in Tourette Syndrome: Results From a Case-Control Study in Children
Federica Graziola1,2, Chiara Pellorca1, Lorena Di Criscio1,2
1Movement Disorders Clinic, Department of Neurosciences, Bambino Gesù Children's Hospital, Rome, Italy.
Insights
Tourette syndrome (TS) patients, with or without ADHD, show impaired motor timing. Pure TS patients tapped "behind the beat," while TS+ADHD patients tapped "ahead of the beat," indicating altered temporal control.
Area of Science:
- Neuroscience
- Developmental Psychology
- Movement Disorders
Background:
- Tourette syndrome (TS) is a neurodevelopmental disorder marked by motor and vocal tics.
- Pediatric TS frequently co-occurs with ADHD or OCD, often involving executive function deficits.
- Motor timing, the temporal organization of motor behavior, is crucial for coordinated movement.
Purpose of the Study:
- To investigate motor timing abilities in children with Tourette syndrome.
- To compare motor timing in pure TS patients versus those with co-occurring ADHD.
- To explore the relationship between motor timing and executive functions in pediatric TS.
Main Methods:
- Thirty-seven pediatric TS patients (22 pure TS, 15 TS+ADHD) and 22 healthy controls were assessed.
- Neuropsychiatric screening and the Tower of London (ToL) test evaluated executive functions.
- Finger-tapping test (FTT) and synchronization-continuation tasks measured motor timing accuracy.
Main Results:
- Both pure TS and TS+ADHD groups exhibited lower FTT scores than controls for both hands.
- In the synchronization-continuation task, both TS groups showed reduced accuracy in supra-second intervals.
- "Pure" TS patients were "behind the beat," while TS+ADHD patients were "ahead of the beat."
- FTT performance correlated inversely with ToL scores and execution time, but not with synchronization accuracy.
Conclusions:
- Children with Tourette syndrome demonstrate impaired motor timing and temporal control of motor behavior.
- Distinct temporal organization patterns were observed between pure TS and TS+ADHD groups.
- These motor timing deficits may stem from shared neurobiological underpinnings in TS and motor timing processes.
Abstract:
Tourette syndrome (TS) is a neurodevelopmental disorder characterized by motor and vocal tics. Co-occurrence of attention-deficit/hyperactivity disorder (ADHD) or obsessive-compulsive disorder (OCD) is very frequent in the 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 behavior, in a pediatric 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, such as Tower of London (ToL). Two experimental paradigms were adopted: finger-tapping test (FTT), a free motor tapping task, and 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 FTT for the dominant and non-dominant hands than controls. Moreover, in the synchronization and continuation test, we observed an overall lack of accuracy in both TS groups in the continuation phase for 2,000 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 ToL total scores and execution time, whereas 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 TS and motor timing.
