title: A MAOA gene*cocaine severity interaction on impulsivity and neuropsychological measures of orbitofrontal dysfunction: preliminary results.
abstract: BACKGROUND
  Based on previous evidence of a MAOA gene*cocaine use interaction on orbitofrontal cortex volume attrition, we tested whether the MAOA low activity variant and cocaine use severity are interactively associated with impulsivity and behavioral indices of orbitofrontal dysfunction: emotion recognition and decision-making.
  
  
  METHODS
  72 cocaine dependent individuals and 52 non-drug using controls (including healthy individuals and problem gamblers) were genotyped for the MAOA gene and tested using the UPPS-P Impulsive Behavior Scale, the Iowa Gambling Task and the Ekman's Facial Emotions Recognition Test. To test the main hypothesis, we conducted hierarchical multiple regression analyses including three sets of predictors: (1) age, (2) MAOA genotype and severity of cocaine use, and (3) the interaction between MAOA genotype and severity of cocaine use. UPPS-P, Ekman Test and Iowa Gambling Task's scores were the outcome measures. We computed the statistical significance of the prediction change yielded by each consecutive set, with 'a priori' interest in the MAOA*cocaine severity interaction.
  
  
  RESULTS
  We found significant effects of the MAOA gene*cocaine use severity interaction on the emotion recognition scores and the UPPS-P's dimensions of Positive Urgency and Sensation Seeking: Low activity carriers with higher cocaine exposure had poorer emotion recognition and higher Positive Urgency and Sensation Seeking.
  
  
  CONCLUSIONS
  Cocaine users carrying the MAOA low activity show a greater impact of cocaine use on impulsivity and behavioral measures of orbitofrontal cortex dysfunction.
authors.affiliation: Department of Clinical Psychology, School of Psychology, University of Granada, Spain; Institute of Neurosciences Federico Olóriz, Centro de Investigacion Biomedica, University of Granada, Spain; School of Psychology and Psychiatry, Monash University, Melbourne, Australia. Electronic address: antonio.verdejo@monash.edu.
authors.forename: Antonio
authors.initials: A
authors.lastname: Verdejo-García
authors.forename: Natalia
authors.initials: N
authors.lastname: Albein-Urios
authors.forename: Esther
authors.initials: E
authors.lastname: Molina
authors.forename: Ana
authors.initials: A
authors.lastname: Ching-López
authors.forename: José M
authors.initials: JM
authors.lastname: Martínez-González
authors.forename: Blanca
authors.initials: B
authors.lastname: Gutiérrez
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D016022:Case-Control Studies; D019970:Cocaine-Related Disorders / Q000235:genetics* / Q000523:psychology; D003657:Decision Making; D005149:Facial Expression; D005625:Frontal Lobe / Q000503:physiopathology*; D005715:Gambling / Q000523:psychology; D005838:Genotype; D006801:Humans; D007175:Impulsive Behavior / Q000150:complications / Q000235:genetics* / Q000523:psychology; D008297:Male; D008875:Middle Aged; D008995:Monoamine Oxidase / Q000235:genetics*; D009483:Neuropsychological Tests; D021641:Recognition, Psychology; D012720:Severity of Illness Index
chemical_list: D008995:Monoamine Oxidase; C579458:monoamine oxidase A, human
keywords: Cocaine; Emotion recognition; Lack of Premeditation; MAOA gene; Positive Urgency; Sensation Seeking