Illness Specific Cognitive Biases in Chronic Fatigue Syndrome Independent of Mood and Attentional Control Deficits

Background: Studies have identified specific cognitions and behaviours play a role in maintaining chronic fatigue syndrome (CFS); however little research has explored illness specific cognitive processing in CFS. This study investigates whether CFS participants have an attentional bias for illness-related stimuli and a tendency to interpret ambiguous information in a somatic way; and determines whether these cognitive processing biases are associated with cognitions and behaviours, mood or attentional control. Methods: Fifty two CFS and 51 healthy participants completed self-report measures of symptoms, disability, mood, and cognitions and behaviours; and three experimental tasks, using materials specifically designed to tap into CFS salient cognitions (i) Visual-Probe task measuring attentional bias to illness (disability and somatic) versus neutral words (ii) Attention Network Test measuring attentional control (iii) recognition task measuring positive versus somatic interpretations of ambiguous information. Findings: Compared to controls, CFS participants showed a significant attentional bias for illness words; and were significantly more likely to interpret ambiguous information in a somatic way; even when controlling for co-morbidity. The CFS group had significantly poorer attentional control than healthy participants; which was not related to cognitive biases. Somatic interpretations were associated with self-reported fatigue, catastrophizing and fear/avoidance beliefs. Disucssion: People with CFS have illness specific biases in how information is attended to and interpreted, which may play a part in maintaining symptoms by reinforcing negative illness beliefs and behaviours. Enhancing adaptive processing, such as positive interpretation biases and more flexible attention allocation, may provide beneficial intervention targets.