Computerized training improves verbal working memory in patients with myalgic encephalomyelitis/chronic fatigue syndrome: A pilot study.

Abstract

OBJECTIVE: Patients with myalgic encephalomyelitis/chronic fatigue syndrome experience cognitive difficulties. The aim of this study was to evaluate the effect of computerized training on working memory in this syndrome. DESIGN: Non-randomized (quasi-experimental) study with no-treatment control group and non-equivalent dependent variable design in a myalgic encephalomyelitis/chronic fatigue syndrome-cohort. SUBJECTS: Patients with myalgic encephalomyelitis/chronic fatigue syndrome who participated in a 6-month outpatient rehabilitation programme were included in the study. Eleven patients who showed signs of working memory deficit were recruited for additional memory training and 12 patients with no working memory deficit served as controls. METHODS: Cognitive training with computerized working memory tasks of increasing difficulty was performed 30-45 min/day, 5 days/week over a 5-week period. Short-term and working memory tests (Digit Span - forward, backward, total) were used as primary outcome measures. Nine of the 11 patients were able to complete the training. RESULTS: Cognitive training increased working memory (p = 0.003) and general attention (p = 0.004) to the mean level. Short-term memory was also improved, but the difference was not statistically significant (p = 0.052) vs prior training. The control group did not show any significant improvement in primary outcome measures. CONCLUSION: Cognitive training may be a new treatment for patients with myalgic encephalomyelitis/chronic fatigue syndrome.