Working memory deficits in chronic fatigue syndrome: Differentiating between speed and accuracy of information processing

To examine the relative influence of speed of information processing <e1>versus</e1> working memory ability, CFS participants with psychiatric comorbidity (CFS–Psych) and CFS without a psychiatric history (CFS–noPsych) were examined on tests of visual and auditory processing speed and visual and auditory working memory. Compared to healthy controls (HC) and a group of participants with rheumatoid arthritis (RA), the CFS–noPsych group displayed significantly reduced performance on tests of information processing speed, but not on tests of working memory. No significant differences were observed between the CFS–Psych group and any other group in the study. The implications of group heterogeneity on the understanding of cognitive impairment in CFS are discussed. (<e1>JINS</e1>, 2004, <e1>10</e1>, 101–109.)