Alterations in brain connectivity in Tourette's syndrome
3 September 2019
Shukti Ramkiran, Larissa Heidemeyer, Arnim Gaebler, N. Jon Shah, Irene Neuner
Tourette Syndrome (TS) is a neuropsychiatric disorder characterised by involuntary movements and vocalizations known as tics. It has previously been attributed to a dysfunction of the cortico-striato-thalamo-cortical circuits, although recent evidence suggests a more widespread dysfunction of brain networks could be at play.
This study aimed to characterise brain network dysfunction in TS patients by investigating functional and effective-like connectivity, as well as topological changes of basal ganglia-thalamo-cortical and cortico-cerebellar brain networks. Topological brain network changes were assessed using resting-state fMRI data from 28 TS patients and 28 aged-matched, healthy control subjects.
The results showed increased connectivity and functional integration of multiple basal ganglia-thalamo-cortical circuits in the TS patients, suggesting a predominance of excitatory neurotransmission and a lack of brain maturation. The results also indicate that the role of topological changes in the cortico-cerebellar and the brain networks involved in interoception may have been previously underestimated in terms of the neural correlates of tics and the crucial premonitory urge feeling.
The results of this study point to a highly complex process leading to tic formation and further research is required in order to fully comprehend the relationship between brain network dysfunction and TS.