Differential modulation of neural oscillations in perception-action links in Tourette syndrome

Gilles de la Tourette Syndrome (GTS) is a multi-faceted neuro-psychiatric disorder. While novel conceptions overcoming the criticized categorization of GTS as a movement disorder are on the rise, little is known about their neural implementation and whether there are links to known pathophysiological processes in GTS. This is the case for conceptions suggesting that aberrant perception-action processes reflect a key feature of GTS. Building on the concept that overly strong perception-action associations are pivotal to understanding GTS pathophysiology, we examined how these associations influence response inhibition and used EEG methods to examine the importance of theta, alpha and beta band activity due to their known relevance for GTS pathophysiology. In this case-control study, behavioural analyses revealed that adult patients with GTS experienced greater difficulty during motor response inhibition when perceptual features of Nogo stimuli overlapped with perceptual features of Go stimuli, indicating impaired reconfiguration of perception-action associations. Neurophysiological findings showed robust differential patterns of modulation in theta and alpha band activity between neurotypical (NT) individuals and GTS patients. Specifically, GTS patients exhibited stronger and more extended theta band modulation but weaker and more restricted alpha band modulation during overlapping Nogo trials than NT individuals. Unlike NT individuals, GTS patients did not exhibit beta band modulations necessary for dynamically handling perception-action codes. The findings highlight increased theta band modulation in GTS patients' significant stronger perception-action bindings and a lack of compensatory alpha band modulation. The robust differential modulation observed provides novel insights, emphasizing theta and alpha oscillations as key elements in GTS pathophysiology and offering potential implications for targeted cognitive-behavioural interventions.