Neurocognitive Functioning in Alcohol Use Disorder: Cognitive Test Results Do not Tell the Whole Story.

OBJECTIVES: It is textbook knowledge that individuals with alcohol use disorder (AUD) show large neurocognitive deficits. However, these patients display a number of additional impairments (e.g., lack of drive and motivation) that may contribute to poor test results. The impact of these secondary mediators has not been explored systematically. Based on prior findings that low performance motivation, a negative attitude toward cognitive assessment, and momentary symptoms compromise neuropsychological test results in depression, schizophrenia, and obsessive-compulsive disorder, we examined the possibility that impaired test results in AUD partially represent an epiphenomenon.

METHODS: Fifteen patients with AUD and 20 matched nonclinical individuals underwent a comprehensive neuropsychological test battery. The neurocognitive assessment was flanked by the Momentary Influences, Attitudes and Motivation Impact on Cognitive Performance Scale (MIAMI), which captures momentary influences affecting performance.

RESULTS: Patients with AUD performed worse than nonclinical controls on most test parameters. Group differences achieved a very large effect size for parameters tapping speed and accuracy. Patients with AUD showed deviant scores, particularly on the post version of the MIAMI (retrospective assessment of symptoms and influences during testing) and the total scores. For accuracy, the MIAMI scores represented a partial mediator. For speed, significant group effect sizes were rendered nonsignificant when the MIAMI was taken into account.

CONCLUSION: Like other psychiatric patients, patients with AUD show marked neurocognitive impairments that seem to be aggravated by, for example, distraction and lack of effort. This tentatively suggests that performance only partly reflects cortical impairments in areas hosting neurocognitive faculties. Contextual factors deserve greater attention in patients with addiction. The cross-sectional design of our study limits conclusions relating to causality.