Subjects were instructed to refrain from using alcohol and substances for at least 5 days prior to EEG recording. Subjects were excluded from neurophysiological assessment if they had any of the following: (1) recent substance or alcohol use (i.e., positive breath-analyzer test), (2) hepatic encephalopathy/cirrhosis of the liver, (3) history of head injury, seizures or neurosurgery, (4) uncorrected sensory deficits, (5) use of medication known to influence brain functioning, and (6) other acute/chronic medical illnesses that affects brain function.
