MEMORY, ATTENTION, AND EXECUTIVE FUNCTION IN CHRONIC FATIGUE SYNDROME

Objectives-To examine cognitive function in chronic fatigue syndrome. Methods-Twenty patients with chronic fatigue syndrome recruited from p rimary care and 20 matched normal controls were given CANTAB computeri sed tests of visuospatial memory, attention, and executive function, a nd verbal tests of letter and category fluency and word association le arning. Results-Patients with chronic fatigue syndrome were impaired, predominantly in the domain of memory but their pattern of performance was unlike that of patients with amnesic syndrome or dementia. They w ere normal on tests of spatial and pattern recognition memory, simulta neous and delayed matching to sample, and pattern-location association learning. They were impaired on tests of spatial span, spatial workin g memory, and a selective reminding condition of the pattern-location association learning test. An executive test of planning was normal. I n an attentional test, eight subjects with chronic fatigue syndrome we re unable to learn a response set; the remainder exhibited no impairme nt in the executive set shifting phase of the test. Patients with chro nic fatigue syndrome were also impaired on verbal tests of unrelated w ord association learning and letter fluency. Conclusion-Patients with chronic fatigue syndrome have reduced attentional capacity resulting i n impaired performance on effortful tasks requiring planned or self or dered generation of responses from memory.