Concurrent PET D2/D3 Receptor Imaging and fMRI Smoking Cue Reactivity in Smokers

Inclusion Criteria: * competent to provide written informed consent * Smokers: self-report of smoking 15 or more cigarettes/day for the past year, self-report of smoking first cigarette of the day within 30 minutes of awakening, meets DSM-IV criteria for Nicotine Dependence, provides expired breath carbon monoxide reading of \> 10 ppm at enrollment * Nonsmokers: self-report of consuming \<100 cigarettes in their lifetime, none in the last 6 months, provides expired breath carbon monoxide reading of \< 9 ppm at enrollment * Women of childbearing potential: negative STAT serum beta-human chorionic gonadotrophin pregnancy test before scanning Exclusion Criteria: * pregnant or able to become pregnant and not willing to undergo blood pregnancy test * unstable medical illness with likely hospitalization for treatment within 6 months * life-threatening arrhythmia, cerebro-vascular or cardiovascular event within 6 months of enrollment; liver function tests elevated over 2.5x normal; CNS tumor or seizure disorder * users of other tobacco- or nicotine-containing products (gum, patches, e-cigarettes) * lifetime history of DSM-IV bulimia, organic mental disorder, brain injury or psychotic disorder * 6 month history of non-nicotine substance use disorder or major depression * history of multiple adverse drug reactions * current use of excluded concomitant medications (smoking cessation medications) * known history of allergic reaction to the PET ligand \[11C\]-PHNO, its components, or any medication