Evaluation of EEG biomarkers of Comprehensive Behavioral Intervention for Tics in children with Tourette syndrome

Abstract

ObjectiveComprehensive Behavioral Intervention for Tics (CBIT) is a first-line treatment of Tourette syndrome (TS). However, the brain mechanisms involved in CBIT are poorly understood. Enhanced frontomesial EEG coherence during a Go/NoGo task has been suggested as a mechanism involved in voluntary tic control. In the current study, we conducted a randomized controlled trial to assess whether EEG coherence during a Go/NoGo task was associated with CBIT outcome. MethodsThirty-two children with TS were randomly assigned to CBIT or to treatment-as-usual (TAU). Treatment outcome was assessed by a blinded evaluator with the Yale Global Tic Severity Scale (YGTSS) and the Clinical Global Impression – Improvement Scale (CGI-I). EEG was recorded during a Go/NoGo task at baseline and endpoint. EEG coherence was computed in the alpha frequency band between a priori selected channel pairs spanning the frontal and motor areas. ResultsTic severity decreased significantly in the CBIT group. However, CBIT did not impact EEG coherence and baseline EEG coherence did not predict treatment outcome. ConclusionsAlthough CBIT was superior to TAU on blinded clinical outcomes, EEG coherence during the Go/NoGo task was not associated with change in tic severity. SignificanceThe brain processes involved in the inhibition of motor responses do not appear to be involved in CBIT.