participants were asked about their alcohol and drug use over the past 12 hours and were given a breath alcohol test using an Alco Sensor IV (Intoximeters Inc., St. Louis, MO). If a participant reported using any drugs within the past 12 hours, had a breath alcohol level above 0.0%, reported feeling hung over or sleepy, or were unable to answer test questions, they were excluded from participation at that session and rescheduled.