Working Memory Training in Alcohol Use Disorder: A Randomized Controlled Trial

Abstract

Background: Alcohol use disorder (AUD) is associated with cognitive deficits such as impaired executive functions, which are hypothesized to contribute to the progression of the disease and worsen treatment outcome. Training of working memory (WM) to improve cognitive functions and thereby reduce alcohol use has been proposed as a novel treatment strategy.

Methods: Patients with AUD (n = 50) who were recruited to an outpatient addiction clinic were randomized to receive 5 weeks of active WM training or control training. Participants had weekly follow-up visits, and all cognitive training sessions were done online at home. Primary outcomes were WM function and change in self-reported heavy drinking. Secondary outcomes were craving, other drinking outcomes, and performance on a range of neuropsychological tasks from the Cambridge Neuropsychological Test Automated Battery.

Results: The active training group demonstrated a significantly greater improvement in verbal WM compared with the control group. No statistically significant effect of training was found on the primary drinking outcome, but a trend was observed indicating that WM training reduces the number of drinks per drinking occasion. WM training had no statistically significant effect on any of the other neuropsychological tasks.

Conclusions: Cognitive training can improve WM function in individuals with AUD, suggesting that such interventions are feasible to administer in this patient population. The results do not support an effect of WM training on heavy drinking or transfer effects to other cognitive domains. Future studies should evaluate WM training as an adjunct to evidence-based treatments for AUD to assess potential synergistic effects.

Trial registration: ClinicalTrials.gov NCT02113618.

Keywords: Alcohol Use Disorder; Cogmed; Cognitive Training; Working Memory.

Figure 1

CONSORT (Consolidated Standards of Reporting Trials) flowchart illustrating the flow of study participants. AUD, alcohol use disorder; WM, working memory; ITT, intention to treat; PP, per protocol.

Figure 2

Digit Span scores at baseline and test day in participants who completed the study. The total score (A) and backward score (B) were significantly improved in the treatment group compared with controls. No statistically significant difference was found for the forward score (C). Values are presented as mean ± standard error of the mean; *p < 0.05.

Figure 3

Spatial Working Memory task performance in participants who completed the study. The main outcomes were total errors (A), strategy (B), between‐errors (C), and within‐errors (D) at baseline and test day for treatment and control groups. There were no significant differences between treatment groups. Values are presented as mean ± standard error of the mean.

Figure 4

Self‐reported drinking in participants who completed the study using the Timeline Followback interview method at baseline (90 days before study) and test day (during study period). There was no significant effect of treatment on percentage of heavy drinking days (A), drinks per drinking day (B), percent drinking days (C), or drinks per day (D), but a trend (p = 0.069) was observed indicating decreased drinks per drinking day in the treatment group compared with the control group (B). Values are presented as mean ± standard error of the mean.

Figure 5

Self‐reported craving (A) and mood (B) at baseline, weekly visits, and test day for treatment group and control group in participants who completed the study. There were no significant differences between treatment groups. Values are presented as mean ± standard error of the mean. Short‐DAQ, Swedish shortened version of the Desire for Alcohol Questionnaire; MADRS‐S, Montgomery–Asberg Depression Self‐Rating Scale.