Project 2: Longitudinal development of perception-action integration in GTS: in search for mechanisms underlying symptom remission

• Applicants: Professorin Shu-Chen Li, Ph.D.; Professor Dr. Alexander Münchau
• Subject Area: Developmental Neurobiology ; Clinical Neurology; Neurosurgery and Neuroradiology
• Term: since 2022
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 360279285

Gilles de la Tourette syndrome (GTS) is a prototype neurodevelopmental disorder typically commencing in early school age. In many patients symptoms partially or completely remit during adolescence, in a considerable proportion of patients the symptoms persist into adulthood and may then even deteriorate. The reasons for individual differences in symptom remission and persistence are unclear. Identifying biological markers predicting which children / adolescents with GTS are more likely to undergo remission and which are at risk of developing persisting GTS may profoundly affect patient management. Thus, in patients, in whom such biological markers indicate symptom remission a permissive attitude and general measures including coping strategies, psychosocial counselling, and transient symptomatic pharmacological measures may suffice. However, in patients with likely symptom persistence more intensive interventions to foster compensatory cognitive strategies including cognitive behavioral treatment in addition to general means may be required. Perception-action processing, extensively studied in the first funding period, is an attractive biological marker because abnormal binding of perceptual and motor processes has emerged as a key finding in GTS. Adults with persisting GTS showed an increased binding strength correlating with tic frequency suggesting a tight pathophysiological link between event file coding and the presence (or persistence) of tics. On the other hand, event file coding was normal at the behavioral level in children and adolescents with GTS, although underlying neural activation patterns differed from age-matched healthy controls suggesting that increased binding strength as a possible sign of lack of neurodevelopment of perception-action integration processes is not a characteristic of the GTS population as a whole, but rather of those GTS patients with symptoms persisting into adulthood. Focusing on developmental aspects of GTS in the second funding period, Project 2 aims to identify patterns of longitudinal developmental changes in perception-action integration that differentiate between processes of developmental normalization underlying symptom remission and those of continuing atypical development leading to symptom persistence or deterioration in adulthood. This will be addressed using established behavioral paradigms and concomitant EEG investigations including RIDE-decomposed EEG data analysis, analysis of oscillatory EEG activity and source localization.

• DFG Programme: Research Units
• Subproject of: FOR 2698: Cognitive theory for Tourette syndrome – a novel perspective
• Co-Investigator: Dr. Julius Verrel