People with chronic fatigue syndrome (CFS) have increased rates of depression, anxiety, and illness intrusiveness;
they may also suffer from cognitive problems such as retrospective memory (RM) deficits and concentration
difficulties that can stem from diminished information-processing capability. We predicted that this
diminished capacity may also lead to deficits in other cognitive functions, such as prospective memory (ProM).
Event-, time-, and activity-based ProM was assessed in 11 women with CFS and 12 healthy women using a
computer-generated virtual environment (VE). RM was assessed using a free-recall test, and subjective assessment
of both ProM and RM was assessed by questionnaire. Groups were equivalent in age and measures of IQ.
People with CFS performed slightly worse than healthy controls on both the event- and time-based ProM
measures, although these were not statistically significant. However, the CFS group performed significantly
worse than the healthy controls on both the free recall-task and on subjective assessment of both RM and ProM.
Women with CFS do have some subtle decrements in memory, particularly RM. However, it is possible that the
decrements found in the present sample would be greater in real life. Further studies utilizing both healthy
controls and illness controls are now needed to ascertain how sensitive the VE measure is and to inform the
development of tasks in the VE that place progressively increasing demands on working memory capacity
