GPI and Timothy syndrome: Cavanna et al. (6) cite four key reasons for GPi as their preferred target for TS: (1) GPi plays a central role in the cortico-striato-thalamo-cortical circuitry involved in TS pathophysiology; (2) GPi has been shown to be more effective than thalamic DBS in one small series (21); (3) lack of side effects with GPi stimulation; (4) GPi is readily visible on MRI for more facile implantation.