title: Complexity changes of the EEG induced by alcohol cue exposure in alcoholics and social drinkers.
abstract: BACKGROUND
  An understanding of the neurophysiological mechanisms underlying alcohol craving is important in the effective treatment of alcohol dependence. The aim of this study was to examine the utility of the electroencephalogram (EEG) to measure the changes in electrical brain activity of alcoholics when exposed to alcohol-specific cues.
  
  
  METHODS
  Fifteen adult alcoholic subjects (four women) with a mean age of 35 (SD = 4.5) and 10 healthy social drinking controls (three women) with a mean age of 34 (SD = 5.6) were recruited. Subjects were serially rated for alcohol craving after presentations of pictures of control nonalcoholic and alcohol beverages. After the picture presentation, the EEG was recorded (16,384 data points for each epoch) with eyes closed. The dimensional complexity (D2) was estimated as a measure of complexity of the EEG.
  
  
  RESULTS
  Alcoholic subjects exhibited a significant increase in the D2 values of the EEG in frontal (F3, F4), right posterior temporal (T6), and occipital (O1, O2) regions after viewing alcohol cues compared with viewing other beverage cues. These results indicate that more complex (or higher) cortical activity is induced over specific brain regions of alcoholic subjects by alcohol-specific cues. Changes in subscale of alcohol craving between nonalcoholic and alcohol pictures were correlated with changes in D2 values in the left frontal (F3) region in alcoholic subjects.
  
  
  CONCLUSIONS
  These findings suggest that, when subjects are exposed to alcohol cues, changes in the EEG complexity are induced in frontal, right posterior temporal, and occipital areas, which may be key brain structures for alcohol craving. In addition, nonlinear measures like the D2 are useful in evaluating alcohol cue-induced brain activity from the EEG.
authors.affiliation: College of Medicine, The Catholic University of Korea, Seoul, South Korea.
authors.forename: Dai-Jin
authors.initials: DJ
authors.lastname: Kim
authors.forename: Jaeseung
authors.initials: J
authors.lastname: Jeong
authors.forename: Kwang-Soo
authors.initials: KS
authors.lastname: Kim
authors.forename: Jeong-Ho
authors.initials: JH
authors.lastname: Chae
authors.forename: Seung-Hyun
authors.initials: SH
authors.lastname: Jin
authors.forename: Kook Jin
authors.initials: KJ
authors.lastname: Ahn
authors.forename: Hugh
authors.initials: H
authors.lastname: Myrick
authors.forename: Su-Jung
authors.initials: SJ
authors.lastname: Yoon
authors.forename: Hyung-Rae
authors.initials: HR
authors.lastname: Kim
authors.forename: Soo Yong
authors.initials: SY
authors.lastname: Kim
mesh_terms: D000328:Adult; D000428:Alcohol Drinking / Q000503:physiopathology* / Q000523:psychology; D000437:Alcoholism / Q000503:physiopathology* / Q000523:psychology; D000704:Analysis of Variance; D003463:Cues; D004569:Electroencephalography / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D017711:Nonlinear Dynamics; D010775:Photic Stimulation / Q000379:methods*