Brain Imaging of Cocaine Craving in Recreational Cocaine Users

Inclusion Criteria: * Subjects must be able to provide informed consent and function at an intellectual level sufficient to allow accurate completion of all assessment instruments. * Subjects must report having used cocaine within the past 3 months. Subjects may meet criteria for abuse, but not dependence on any other substance with the exception of nicotine, marijuana and alcohol. * Use of one of the following methods of birth control by female subjects: birth control pills, barrier methods (diaphragm or condoms with spermicide or both), surgical sterilization, use of an intra-uterine contraceptive device, or complete abstinence from sexual intercourse. * Subjects must live within a 50-mile radius of the research facility and have reliable transportation. * Subjects must consent to remain abstinent from all drugs of abuse (except nicotine) prior to the experiment. * Subjects must be right-handed. Exclusion Criteria: * Women who are pregnant, nursing or of childbearing potential and not practicing an effective means of birth control. * Subjects with evidence of or a history of significant hematological, endocrine, cardiovascular, pulmonary, renal, gastrointestinal, or neurological disease including diabetes, as these conditions may affect heart rate or skin conductance measurement. * Subjects with a history of or current psychotic disorder as this may impact cue reactivity. * Subjects who are unwilling or unable to maintain abstinence from alcohol and other drugs of abuse (except nicotine). * Subjects meeting DSM-IV criteria for substance dependence (other than nicotine, marijuana, or alcohol) within the past 60 days. Subjects may not meet criteria for cocaine dependence at any time. * Subjects currently taking B-blockers, anti-arrhythmic agents, psychostimulants or any other agents known to interfere with heart rate and skin conductance monitoring. * Subjects with a history of epilepsy or seizure disorder. * Subjects with significant liver impairment. * The need for maintenance or acute treatment with any psychoactive medication including anti-seizure medications which could potentially interfere with fMRI. * Clinically significant psychiatric or medical problems that would impair participation or limit ability to participate in scan. * Persons with ferrous metal implants or pacemaker since fMRI will be used.