Measures of hDAT availability in the human brain had been collected using PET and [11C]cocaine, a radioligand to measure hDAT, and retrieved from the imaging dataset of the BNL Brain Imaging Center. All PET scans were performed on a Siemens, HR+ scanner in 3D mode via procedures as reported35 (link) along with the analytical approach to quantify the availability, which was estimated as Bmax/KD36 (link), 37 (link). For this study we only used data obtained in 62 healthy male controls (average age at 35.1 years with a standard deviation of 6.7; N=27 African Americans, 28 Caucasians, 3 Hispanics, and 4 multiracial).