Cognition-induced modulation of serotonin in the orbitofrontal cortex: A controlled cross-over PET study of a delayed match-to-sample task using the 5-HT2a receptor antagonist [18F]altanserin

► [18F]altanserin PET investigates cognition induced changes at the 5-HT2a receptor. ► Binding potentials of working memory (WM) and a control task are compared voxelwise. ► WM induces an increased binding potential in orbitofrontal cortex, but no decreases. ► Results point to an orbitofrontally reduced serotonin release at the 5-HT2a receptor. ► This indicates optimization of the WM-related central executive via 5-HT2a receptors.