After the drug and alcohol tests, participants ate a light breakfast (with a caffeinated beverage for those individuals who regularly consumed caffeine) and then completed the baseline assessment battery that consisted of computerized questionnaires and performance tasks. Immediately following the baseline assessment battery, participants ingested two capsules and a 350 ml beverage. The assessment battery was repeated at 0.5, 1, 2, 3 and 4 h after dosing. Additional breath alcohol levels were measured at 15 min and 90 min after dosing. After the 3 h assessment battery, participants were given 30 min to eat lunch. At the end of each session, participants were evaluated for signs of intoxication and were required to pass a field sobriety test. Participants were not allowed to leave the laboratory until breath alcohol concentrations were ≤20 mg/dl. As a safety precaution, they were not allowed to drive to and from the laboratory; they were provided subway fare at the end of each session. If the participant was still impaired, she either remained at the laboratory until the drug effects subsided or she was transported home
