However, in contrast to all recent imaging studies in TS1–3, in this study SERT binding was increased in patients with TS + OCD in caudate and midbrain (and possibly further brain areas), while other investigators reported about significantly decreased SERT binding potentials in the midbrain2,3, caudate, and putamen2,3 or no change1 compared to healthy controls. Here, SLC6A4 is linked to Compulsive behaviors.