Figure 3: (a) Effect of citalopram on 11C-DASB PET scan of the serotonin transporter in a depressed subject. Treatment was with 20 mg/day of citalopram for 4 weeks. Adapted from [73]. (b) Striatal serotonin transporter (5-HTT) occupancy in depressed subjects after 4 weeks of treatment at minimum therapeutic doses of five SSRIs. Adapted from [74].