Slow associative learning in alcohol dependence and the alcohol cue exposure treatment paradox.

Abstract

To examine two explanations for the observation that cue-exposure treatment has not been clearly effective in the treatment of alcohol dependence: do alcohol-dependent individuals have either (1) slower extinction and/or (2) greater contextual specificity of extinction than non-dependent individuals? In two exploratory laboratory experiments we used mixed factorial designs with two-group between-subjects factors and within-subjects factors corresponding to performance in different parts of a computer-based learning task. University of Southampton psychology research laboratories and two addiction treatment services in the city of Southampton, UK. Experiment 1: 74 (54 female) undergraduates from the University of Southampton (age mean = 20.4 years). Experiment 2: 102 (40 female) participants from the University of Southampton, the local community, and from two Southampton alcohol treatment services (age mean = 41.3 years). The Alcohol Use Disorders Identification Test, a 1-week time-line follow-back alcohol consumption questionnaire, the Barratt Impulsiveness Scale (11th edn), and a computerized learning task. Experiment 2 additionally used the 44-item Big Five Inventory, a drug use history checklist, and the Hospital Anxiety and Depression Scale. Experiment 1: light and heavy drinkers did not differ significantly in extinction [extinction block × drinking status interaction, P = 0.761, <math xmlns="http://www.w3.org/1998/Math/MathML"><msubsup><mi>η</mi><mi>p</mi><mn>2</mn></msubsup><mo>=</mo><mn>0.005</mn></math> , 95% confidence interval (CI) = (0,0.028)] or on contextual control of extinction [recovery block × drinking status interaction, P = 0.514, <math xmlns="http://www.w3.org/1998/Math/MathML"><msubsup><mi>η</mi><mi>p</mi><mn>2</mn></msubsup><mo>=</mo><mn>0.009</mn></math> , 95% CI =(0, 0.084)]. Experiment 2: slower extinction in abstinent alcohol-dependent participants compared with light drinkers [extinction block × drinking status interaction, P = 0.023, <math xmlns="http://www.w3.org/1998/Math/MathML"><msubsup><mi>η</mi><mi>p</mi><mn>2</mn></msubsup><mo>=</mo><mn>0.031</mn></math> , 95% CI = 0, 0.069)] but no significant difference on contextual control of extinction [recovery block × drinking status interaction, P = 0.069, <math xmlns="http://www.w3.org/1998/Math/MathML"><msubsup><mi>η</mi><mi>p</mi><mn>2</mn></msubsup><mo>=</mo><mn>0.033</mn></math> , 95% CI = (0, 0.125)]. Abstinent alcohol-dependent people may have slower extinction learning for alcohol-related cues than non-dependent light drinkers.