Attentional biases in irritable bowel syndrome patients

BACKGROUND AND OBJECTIVE

According to the cognitive behavioural model of irritable bowel syndrome (IBS) selective attention to visceral stimuli is one of the pathophysiological mechanisms in IBS. We aimed to investigate attentional biases in patients with IBS and to explore the relationship between neuroticism, trait anxiety, visceral anxiety and indices of attentional biases.

METHODS

Twenty-seven patients completed the global/local task and the modified Stroop task (using 4 word categories: neutral, symptom-related, emotionally and situationally relevant) while 28 healthy persons completed the Stroop task only. Both groups also filled out a set of psychological questionnaires.

RESULTS

The results show two distinct attentional biases in patients with irritable bowel syndrome. The index of global precedence was negatively correlated with neuroticism (r=-.41, P<.05) while there was no correlation of global precedence with trait and visceral anxiety. We found Stroop facilitation (F[3,81]=3.98, P<.02) specifically for situational threat words. Also, there were positive correlations between trait anxiety, visceral anxiety and the Stroop facilitation index for situational threat words (r=.43 and r=.47, P<.05). In the control group, we found neither Stroop facilitation nor interference. But, facilitation index of emotional words was positively correlated with neuroticism (r=.40, P<.05), which is in line with the "emotion congruent attentional bias" in the general population.

CONCLUSIONS

Neuroticism was associated with the reduction in global precedence observed in the global/local task. Trait anxiety and visceral anxiety were associated with Stroop facilitation elicited by situational threat words, which are of particular concern for patients with irritable bowel syndrome. These specific situations do not elicit an attentional bias in healthy participants, which might indicate that the observed facilitation to situational threat words is unique for IBS patients.

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